Normal Van temp gauge reading

[mrbngl]

Hello everyone,

I just replaced a ton of stuff on my Van including a new 180 degree thermostat. My van now runs with the temp gauge perfectly horizontal which concerns me. What is considered a normal reading?

Thanks!

[lucasschwartz]

From my reading here, in various threads regarding the fan clutch, etc- Tim says that he had a van that always did run about that temperature, no matter what he did. Even after modding the fan clutch spring so that it engages at a lower temperature (something I plan to do next time I take the passenger floor out.)

My van is now running at about that same heat- even up to about 7/8 of the white section of the gauge sometimes.

I've replaced the thermostat, the hoses, flushed the coolant system twice and checked the radiator for flow (out of the van), replaced the fan clutch, replaced the coolant temperature sensor, checked the catalytic converter (good flow), and still, that temp is that high now.

I just now put a thermometer probe on my top radiator hose to get an actual temperature reading in degrees- I'll let you know what I find out after a long drive today.

I may also take the radiator out and try to descale it with some lye, as the coolant was looking preeeeeeety dirty throughout the flushing. There could be decent flow in the radiator, but scale could still be preventing good heat transfer.

You might check for codes and see if anything is popping up.

Also, did you put in an OEM thermostat, with the jiggle valve at 11 o'clock? It's a known issue, using an after-market thermostat.

[mrbngl]

From my reading here, in various threads regarding the fan clutch, etc- Tim says that he had a van that always did run about that temperature, no matter what he did. Even after modding the fan clutch spring so that it engages at a lower temperature (something I plan to do next time I take the passenger floor out.)

My van is now running at about that same heat- even up to about 7/8 of the white section of the gauge sometimes.

I've replaced the thermostat, the hoses, flushed the coolant system twice and checked the radiator for flow (out of the van), replaced the fan clutch, replaced the coolant temperature sensor, checked the catalytic converter (good flow), and still, that temp is that high now.

I just now put a thermometer probe on my top radiator hose to get an actual temperature reading in degrees- I'll let you know what I find out after a long drive today.

I may also take the radiator out and try to descale it with some lye, as the coolant was looking preeeeeeety dirty throughout the flushing. There could be decent flow in the radiator, but scale could still be preventing good heat transfer.

You might check for codes and see if anything is popping up.

Also, did you put in an OEM thermostat, with the jiggle valve at 11 o'clock? It's a known issue, using an after-market thermostat.


My dad and I recently took the leaking radiator to a local shop that fixed it and cleaned it. While we were doing that we replaced the timing chain, water pump, dizzy cap and rotor, plugs, plug wires, and coolant hoses. We installed a non oem 180 thermostat but I also purchased an oem 180 thermostat and a non oem 170 thermostat. The van runs at about the middle of the white portion of the gauge and at times up to the 3/4 portion of the gauge. Before doing any of this it was rare for the gauge to creep up to 1/3 of the gauge so we are thinking that the thermostat was stuck open because the heater never worked very well either.

I'm just trying to figure out if I should be worried about the current temp it is running at?

Should I swap in the oem 180 or try the non oem 170?

[trestlehed]

Timsrv ALWAYS recommends using the Toyota OEM 180 degree thermostat.

Use the search function.

[mrbngl]

Timsrv ALWAYS recommends using the Toyota OEM 180 degree thermostat.

Use the search function.

Sorry to offend you m9, was just asking a question.🍭

[trestlehed]

You didn't offend me at all. Sorry if I came across heavy handed.
Just want to convey that it's better to go OEM on some parts rather than wasting time and money by going cheap only to regret it later. Believe me on that one!:doh:

[mrbngl]

You didn't offend me at all. Sorry if I came across heavy handed.
Just want to convey that it's better to go OEM on some parts rather than wasting time and money by going cheap only to regret it later. Believe me on that one!:doh:


Thank you for the response! Btw at what part of the temp gauge does your needle sit? I have reason to believe that my old thermostat was stuck open. Now my van sits in the middle and sometimes wanders to the 3 oclock position.

[NewVanOwner]

Recently picked up a van and the temperature gauge will sometimes sit slightly above the midpoint. Is that still normal? Or, should there be a dead-spot to the left it doesn't go over?

Sometimes it will be a millimeter or two to the right of the needle in the photo below. (Toward the edge of the three lines, but not past them.)

Thanks.

https://preview.ibb.co/f0Ujz6/20180117_085141.jpg (https://ibb.co/gY4HK6)

[swamptony]

Hey NewVanOwner,

My van used to get near the end of the squiggly lines as you describe. It wouldn't be in the H, but would get so close and I found it too close for comfort. Turns out I had a faulty water pump. The bearing was shot and I was losing coolant through that bearing at a slow rate at first, but increased as that bearing became more worn.

Are you experiencing any loss in coolant from either the reservoir or filler neck? I wrote a bit about changing my water pump/fan clutch etc in the thread below - may or may not be useful in your case.

http://www.toyotavantech.com/forum/showthread.php?5377-Heater-working-spontaneously-coolant-not-visible-from-filler-neck&p=31339&viewfull=1#post31339

[NewVanOwner]

Thanks for the response. That's a really helpful list you put together in the other thread. Given that the cost of the parts is relatively inexpensive, it definitely seems prudent to simply do them all once I have the engine exposed. At least then I have a good baseline.

It's also cool to know of a radiator place that gets a thumbs up from a van owner. Yuba City is about an hour and a half from me. The more expensive high-flow modification is definitely something to keep in mind for possible future use (this van, or another vehicle).

Do you think my temp gauge going to the edge of those three straight lines indicates an issue? Or is that still 'normal' behavior.

Either way, I am going to just go through the system so I know it's been done, and confidence exists for longer trips.

[swamptony]

Hey NewVanOwner,

While I can't say for sure that there's an issue with your van that's causing it to heat up to that level, in my experience, it would seem that there's an issue in the Fan Clutch, the Water Pump, or a leak somewhere. Obviously, it could be one or more of these issues that's the cause. Tim did a great Fan Clutch video where he shows the proper operation of it so that you can double check yours - however, if you're not sure of the last time you replaced it, and are going for a water pump replacement anyways, it's probably just a good idea to get that done while you're at it.

I actually was very curious about my van running at that temperature level, and couldn't find any definitive answers on whether or not that's a 'safe' range. The only way to know for sure would be to take a temperature reading on the coolant while warmed up. I believe the operating range is something like 180F-220F. Anything above that and you're doing some damage. That said, engines running for prolonged periods in the upper end of that range could see accelerated wear on engine components. Makes senes, more heat = more wear.

I believe most folks' gauges see their gauge below the half way mark under normal driving conditions. Highway driving may see it at the halfway mark, and driving in the hills could see it slightly above that. For what it's worth, now that I've done all those fixes outlined in the thread I linked above, I've not seen my coolant gauge go above half whereas before it was nearing the 3/4 level or the end of those straight lines. I've taken the van on a trip to LA and back from Oakland, CA and even went to Yosemite last weekend without a hitch.

Let me know how it goes for you and thanks for sharing!

[NewVanOwner]

Appreciate the thoughtful response SwampTony.

I think you're right, with vehicles of this age and gauges that might not be finely tuned, it may be difficult to decide exactly whether a particular reading is normal. I will go ahead and replace the parts you helpfully listed. It seems relatively inexpensive (given my free labor), and just a good way to get to know/bond with the van a bit. One always feels more connected to a vehicle after wrenching on it a bit.

I'll also check Tim's fan clutch video, but if I am 'in there' doing the other stuff, I'll likely just spend the 60 bucks so I know it's done.

Thanks again.

[Burntboot]

NVW - As a new to you vehicle, its extremely important to do a thorough evaluation before you jump in and start replacing parts.
What usually happens with that method is you spend your wad on things that seem like a good idea at the time, only to find out a week later that theres something far more important to fix and now your outta bread.
First thing you should scour the forum, theres an awful lot of longtime experience going here and most of the questions you have have already been answered, usually more than once.

As far as the temp gauge goes, ideally it should run in the middle, under load conditions it will creep up a little until the clutch fan tightens up and increases air being drawn through the rad, minor fluctuations are normal, running too cold will cause problems, running too hot will too
Seeing the needle go beyond the squiggly lines would be my point of intervention, the top of the gauge is Red for a reason, you don't want to go there.

Aftermarket thermostats are notorious for causing strange issues and thats the first thing you should start with.
Install the new OEM stat, with the jiggle valve correctly oriented, drain as much coolant out and inspect it, install fresh 50/50 mix and bleed the system.
Of course while you're in there look at everything, rad cap, overflow hose and inspect for signs of leakage.

Then once its running, drive it but pay attention to everything (one eye on the temp gauge at all times), monitor for leaks, see what the gauge does.
Preventative maintenance is great caps, hoses, anything that appears marginal should be replaced, anything rubber should be replaced with proper clamps installed but water pumps are relatively solid and unless there showing signs of leakage at the vent hole its not likely an issue.
Tim has right up somewhere that he took apart an engine that was full of debris, its an eye opening read.

The clutch fan is easy to evaluate, it should roar on a cold start at least for a bit and the same noise should occur when the engine gets hotter than normal.
If it doesn't do that, instal OEM (Denso) and be done with it, but if its working correctly, your van will find a way for you to spend that money soon enough.

Many vans get sold when the PO can't solve an over heating issue and everyone always worries about the possible head gasket repair but thats another good reason to hold off on going hog wild, at least until you know just what you have and what you really need to do.
Its time to make a list and prioritize it to your budget.

[Carbonized]

Often over looked : Missing bottom half of the fan shroud, particularly on a 4WD with Air Con.:wnk:

[hughdawgmmkay]

Hey guys,

I’ve been driving around my ‘84 van with my newly rebuilt engine and started noticing my temp gauge is sitting at 3/4 the gauge when at full operating temperature.

I replaced the temp sensor and fan clutch, and am still getting the same results.

I have also been using my infrared thermometer and clock the engine at 195-206 degrees F at full operating temperature.

I read on the forum that many people’s gauge sits around half way, so I would like to ask help on if my gauge reading is normal or an issue, and more specifically, of the engine running up to 206 degrees F is an issue.

Any input put would be very helpful!

Thanks,
Hugh

[Burntboot]

Welcome to the club, Hugh

So, first off, that thing on your dash is at best a representation of whats actually going on in the engine.
Usually they are fairly accurate but they have been known to read incorrectly. Failures are rare enough that I wouldn't jump to that conclusion until I ruled out everything else, repairs are too expensive to be gambling on things like hot engines.

For the record there are 2 temperature senders, one for the gauge and one for the ECU, I only mention as I have seen people repeatedly replace the one trying to solve a problem, only to find out later, its the other they are after all along.

206* shouldn't cause any trouble, however you're only reading the external metal temperature, not what the coolant is doing inside the motor
One does not always correlate to the other.

I'd start with replacing the T-stat, I know you just had it rebuilt and they probably changed it, but unless you KNOW they put OEM in, change it as a matter of course.
There have been a litany of failures with A/M stats, with most of them showing weird behaviour as opposed to total failure.

Sometimes the only way to know where you're at is to get up close and personal with all the bits involved, as you work through the system in a methodical manner, eliminating things as you go. That way you know EXACTLY what you have and where you need to spend your money, effectively.

When you get to the end you will either have solved the problem or eliminated a whole pile of possibilities.
Knowing exactly the condition of the bits involved is so much more satisfying than "well the person working on it told me it was all good"
I have been burnt by that phrase more times than I care to count.
I don't care how good a tech is, few will care as much about the vehicle they are working on, as the owner of said vehicle will.
Also, if you run into something while you're in there, many techs (at least flat rate techs) may conveniently ignore that other issue.
Either because its a pita to address, it hasn't been authorized, they won't get paid or because they know they'll have more bills to pay again next month
(aka "return for more work")

Caveat - there are some shops out there that go the extra mile, take care of their clients and consider customer satisfaction more important than the bottom line.


BB

[hughdawgmmkay]

Burnbot, I really want to thank you for taking the time reply and help out here! I went through every single item I knew to look at on my own, and finally took it to the local specialty shop for their input.

After pressure testing, the guys found the radiator had a small leak, causing the system to never get up to full pressure to cool properly. Sounds about right to me since I personally installed the t-stat, water pump, fan clutch, and coolant temp sensor and felt pretty confident in these pieces.

We couldn't find a replacement radiator, so we pulled it and took it to a specialty shop here in Atlanta where they could rebuild and repair my existing radiator.

Fingers crossed I get back on the road soon!

Thank you again!
Hugh

[timsrv]

I agree with Burntboot. With all you've invested, I just wanted to add emphasis on making sure you put in the Toyota brand T-stat. The 4y engine requires a specific range of T-stat movement to cool properly. There are several aftermarket brands that are sold for the van that will fit properly, however, their range of movement may not optimize flow and engine cooling. I had ignored warnings by others and used a "high end" Japanese brand aftermarket thermostat on my van (even had a jiggle valve), and that ended up causing me a lot of head-aches. I replaced a lot more parts before I came back to the T-stat and replacing that with the Toyota brand solved the issue. Tim

[hughdawgmmkay]

I agree with Burntboot. With all you've invested, I just wanted to add emphasis on making sure you put in the Toyota brand T-stat. The 4y engine requires a specific range of T-stat movement to cool properly. There are several aftermarket brands that are sold for the van that will fit properly, however, their range of movement may not optimize flow and engine cooling. I had ignored warnings by others and used a "high end" Japanese brand aftermarket thermostat on my van (even had a jiggle valve), and that ended up causing me a lot of head-aches. I replaced a lot more parts before I came back to the T-stat and replacing that with the Toyota brand solved the issue. Tim

Thank you very much Tim!

I scanned this forum while rebuilding the engine and saw this tip that you and many others gave across the site. I definitely used the Toyota brand T-Stat and obsessively ensured the jiggle valve was at the 11 o'clock position when installing...so if this radiator doesn't fix the van running hot, I'm absolutely purchasing another Toyota brand T-Stat and replacing to make sure.

End of day, the radiator is one of the few items I didn't touch, so I'll feel more confident having it validated by the pros before I get back on the road.

I'll keep you all posted soon!

[Cali Cruiser]

If you are still running hot after the radiator fix, be sure to check your timing and idle speed since these can make the engine run hotter also.

[Cali Cruiser]

Don't forget about checking your fan clutch...make sure it is engaging properly.

[timsrv]

If you are still running hot after the radiator fix, be sure to check your timing and idle speed since these can make the engine run hotter also.

Good point. Also, electronic timing advance issues can make it run hot. After checking the timing, pull your jumper and use your timing light to verify the timing changed from set-point. The most common cause of an electronic advance fault is a failed TPS (Throttle Position Sensor). A search will render much more detailed information on this in the TVT forum.

[hughdawgmmkay]

If you are still running hot after the radiator fix, be sure to check your timing and idle speed since these can make the engine run hotter also.

Incredible insight Cali Crusiser & Tim. Thank you both...I'll check the timing regardless of how the radiator fix turns out with that info.

[hughdawgmmkay]

Good point. Also, electronic timing advance issues can make it run hot. After checking the timing, pull your jumper and use your timing light to verify the timing changed from set-point. The most common cause of an electronic advance fault is a failed TPS (Throttle Position Sensor). A search will render much more detailed information on this in the TVT forum.

Alright Tim and team, here’s the latest.

I got the rebuilt radiator back in and had the shop double check my timing and my temp gauge is still sitting a little bit above half way. I’m thinking this is still too hot for the van to be running so I would definitely welcome your input on next steps.

Here is what I’ve done so far:
-Rebuilt radiator
-Timing set
-Throttle linkage adjusted
-New fan clutch
-New temp sensor
-New water pump (Toyota)
-New radiator cap (Toyota)
-New thermostat (Toyota)
-New coolant

Here are my thoughts on next steps:
-I bought another Toyota thermostat and gasket in the off chance my last install didn’t have the jiggle valve installed at 11 o’clock. Still waiting on the shipment
-Is checking/replacing the TPS the next step? If so, what does “pull your jumper” mean in your post above, Tim?

Do you all have any other thoughts on items I should be checking? Or am I just being too obsessive about the temp gauge sitting just over half way??

Any input is greatly appreciated.

[boogieman]

sometimes newly rebuilt engines may run a bit warmer before theyre broken in...theres alot more friction going on before things find their home...
the other thought is some other drag in the drivetrain or accessories? recently i had a power steering tensioner pulley go bad and when the belt was removed i noticed a drop in the temp gauge.

[hughdawgmmkay]

All,

Thank you for your help so far!

Boogieman - Great input, thank you for the tips. The strange thing is my engine ran at normal operating temp for the first 1,000 miles, including two 4 hour long driving sessions, and this temp increase popped out of nowhere. I checked my belts and the alternator tension was a little tight for my liking. Other than that I couldn't find anything else to tune up.

Tim - I think I know what you are saying now with "jumper". My van is an '84 so the vacuum advance is via vacuum hoses instead of the jumper. I checked the timing with and without the vacuum advance hose connected and found the advance is working properly. Additionally, I pulled the engine codes and found Code 1, showing the system running as Normal.

To me it seems my only other item is to replace the thermostat again. I personally replaced the first thermostat with a Toyota brand thermostat, and remember ensuring the jiggle valve was set at 11 o'clock.


I'm really at a loss of what to do here...and even have the specialty shop down the street stumped.

Any other thoughts Toyota Van Tech nation?

Here is my gauge after driving in stop and go traffic for 4 miles...

6706

[dennisdcarty]

Are you sure you have the right fan clutch for a 4 x 4? You might put fresh oil in that clutch

[Burntboot]

The fan clutch is a good point and more likely than the OE T-stat you already installed.
I noticed from your list that while the fan clutch is new, it isn't specified as to brand.
If not OEM or at least Denso, it is suspect

See one discussion here

Fan / fluid coupling (fan clutch)

[hughdawgmmkay]

The fan clutch is a good point and more likely than the OE T-stat you already installed.
I noticed from your list that while the fan clutch is new, it isn't specified as to brand.
If not OEM or at least Denso, it is suspect

See one discussion here

Fan / fluid coupling (fan clutch)

Thank you Burntboot and Dennis! I went ahead and purchased an ASIN fan clutch since the one I bought was AM, Duralast.

Fingers crossed this works!

Also, shout out to Tim on the thread Burntboot posted above...I bought the ASIN fan clutch on RockAuto for less than half the Toyota boxed ASIN fan clutch.

-Hugh

[timsrv]

Tim - I think I know what you are saying now with "jumper". My van is an '84 so the vacuum advance is via vacuum hoses instead of the jumper. I checked the timing with and without the vacuum advance hose connected and found the advance is working properly. Additionally, I pulled the engine codes and found Code 1, showing the system running as Normal.

To me it seems my only other item is to replace the thermostat again. I personally replaced the first thermostat with a Toyota brand thermostat, and remember ensuring the jiggle valve was set at 11 o'clock.


I'm really at a loss of what to do here...and even have the specialty shop down the street stumped.

Any other thoughts Toyota Van Tech nation?

Here is my gauge after driving in stop and go traffic for 4 miles...

6706

Sorry for the late reply. Sometimes I get behind and the Van-Tech issues need to take a back burner to money jobs :?:. Yes, you are right, I was referring to the 86 - 89 vans with electronic advance (sorry I didn't check your profile for the year van). On yours you would set the timing with the vacuum line pulled and plugged from the distributor diaphragm, then you would hook the vacuum back up and verify a change with the timing light. Always a good idea to also apply a vacuum to that diaphragm (with your mouth or a mity-vac) to make sure it's pulls in and does not have free-flow (leak).

I would also be concerned if I saw my temp gauge that high, but you need to verify coolant temp at the fill port (be careful as it can be dangerous removing the cap when hot). If the gauge is accurate, I would expect to see it ~220. If it shows to be normal (180 - 195), then I'd make a mental note this gauge location is normal for your van. Better yet, put a more accurate modern temp gauge in so you don't need to wonder.

I didn't have a chance to read everything (I'm running late), but make sure your fan shroud is intact (lower piece is installed) and if you haven't already done so, I would also recommend replacing the clutch part of the fan with an OE quality unit (Aisin). Tim

[hughdawgmmkay]

Sorry for the late reply. Sometimes I get behind and the Van-Tech issues need to take a back burner to money jobs :?:. Yes, you are right, I was referring to the 86 - 89 vans with electronic advance (sorry I didn't check your profile for the year van). On yours you would set the timing with the vacuum line pulled and plugged from the distributor diaphragm, then you would hook the vacuum back up and verify a change with the timing light. Always a good idea to also apply a vacuum to that diaphragm (with your mouth or a mity-vac) to make sure it's pulls in and does not have free-flow (leak).

I would also be concerned if I saw my temp gauge that high, but you need to verify coolant temp at the fill port (be careful as it can be dangerous removing the cap when hot). If the gauge is accurate, I would expect to see it ~220. If it shows to be normal (180 - 195), then I'd make a mental note this gauge location is normal for your van. Better yet, put a more accurate modern temp gauge in so you don't need to wonder.

I didn't have a chance to read everything (I'm running late), but make sure your fan shroud is intact (lower piece is installed) and if you haven't already done so, I would also recommend replacing the clutch part of the fan with an OE quality unit (Aisin). Tim

Thank you for the very detailed response Tim!

I'll double check the vacuum on the vacuum advance and go ahead and change out my fan clutch with an Aisin unit.

I checked my temps at the fill port and I was around 212, so sounds like I'm definitely running hot. I'll also be getting a modern temp gauge so I can know the exact temps from in the vehicle.

Thanks again,
Hugh

[llamavan]

Remember that the 3Y engine (1984-1985 vans in US) is timed @ 8 degrees BTDC, not 12 degrees as for the 4Y. Might not be the problem, but worth verifying.

Gwen

[hughdawgmmkay]

Remember that the 3Y engine (1984-1985 vans in US) is timed @ 8 degrees BTDC, not 12 degrees as for the 4Y. Might not be the problem, but worth verifying.

Gwen

Thank you Gwen! I had the engine timed at 12 degrees when I first noticed the van running hot, but timing it correctly to 8 degrees didn't fix the problem.

Definitely a good and important point thought...as I'm running much smoother after adjusting!

Thanks again,
Hugh

[boogieman]

i think making sure its hitting maxium advance might be an important test..how does the new engine feel compared to before the rebuild? a retarded engine will run hot... not having enough time to burn the charge, it transfers it to exhaust valves, manifold, and head..

[swamptony]

Hey Hugh,

Sorry, this may be asking the obvious - but are you losing any coolant at all? I had a very similar issue I ended up tracing back to the water pump. I noticed you made that change already with an OEM so that's great! I did the same thing, and then had the same problem! Turns out I didn't tighten those bolts down enough and there was still a small leak. Maybe an issue with that gasket too and the gasket sealer goop. What ends up happening is not only do you lose coolant, you can pull air into the system which is the best insulator and can increase engine temp.

Shameless plug of that thread where I explained my repairs/thoughts: http://www.toyotavantech.com/forum/showthread.php?5377-Heater-working-spontaneously-coolant-not-visible-from-filler-neck&p=31339&viewfull=1#post31339

Sounds like you've been diligent about checking and double checking common issues, so you should be getting close!

Just thought I'd throw my 2¢ in - hope you get to the bottom of this!

[hughdawgmmkay]

i think making sure its hitting maxium advance might be an important test..how does the new engine feel compared to before the rebuild? a retarded engine will run hot... not having enough time to burn the charge, it transfers it to exhaust valves, manifold, and head..

Thank you for the input Boogieman. I did verify that my engine is advancing 12 additional degrees with the advance (great input from Tim, verifying the advance is 20 degrees when advancing), so we can check that box!

Honestly the only time I've run the engine is after the rebuild...the previous engine had a blown head and I was only able to get it to run for 5 seconds...so much better!

Thanks again for the help!

[hughdawgmmkay]

Hey Hugh,

Sorry, this may be asking the obvious - but are you losing any coolant at all? I had a very similar issue I ended up tracing back to the water pump. I noticed you made that change already with an OEM so that's great! I did the same thing, and then had the same problem! Turns out I didn't tighten those bolts down enough and there was still a small leak. Maybe an issue with that gasket too and the gasket sealer goop. What ends up happening is not only do you lose coolant, you can pull air into the system which is the best insulator and can increase engine temp.

Shameless plug of that thread where I explained my repairs/thoughts: http://www.toyotavantech.com/forum/showthread.php?5377-Heater-working-spontaneously-coolant-not-visible-from-filler-neck&p=31339&viewfull=1#post31339

Sounds like you've been diligent about checking and double checking common issues, so you should be getting close!

Just thought I'd throw my 2¢ in - hope you get to the bottom of this!

Great input, thanks so much Swamptony.

I was previously loosing coolant and had the shop down the street perform a pressure test. It turns out my radiator had a small leak and a full rebuild fixed this issue up.

So far, no more coolant loss!

I just replaced the fan clutch last night so I'm hoping tomorrow I can get it out on the road to test it out.

-Hugh

[hughdawgmmkay]

I would also be concerned if I saw my temp gauge that high, but you need to verify coolant temp at the fill port (be careful as it can be dangerous removing the cap when hot). If the gauge is accurate, I would expect to see it ~220. If it shows to be normal (180 - 195), then I'd make a mental note this gauge location is normal for your van. Better yet, put a more accurate modern temp gauge in so you don't need to wonder.


Alright Tim and Toyota Van Tech nation, I have another update.

I replaced the fan clutch with an ASIN clutch and I am no longer creeping up to red. I am however, still rising up to 3/4 :pissed:.

I have an infrared thermometer and I checked the temp on the coolant fill port (driver side middle of the fill port), and it was around 190-200, even when the gauge was at 3/4. I'm thinking this is ok, and maybe just showing that my gauge is reading high? It turns out my head was reading 212, and not the coolant fill port. Any thoughts?

At this point I have replaced the following items, and don't know what else to do other than just get a modern temp gauge to ease my worried mind.

Progress so far:

Rebuilt radiator
OEM water pump
OEM thermostat, correctly installed with jiggle at 11'
OEM radiator cap
OEM upper & lower coolant hoses
Aftermarket temperature sending unit (well, maybe I should get OEM here too...)
Timing verified correct
Timing advance verified correct
Coolant burped


That's it for now, thank you all so much for your help to this point!

-Hugh

[timsrv]

It sounds like you're making progress, so that's good. Personally, I wouldn't waste any more time on this before 1st verifying there is a problem, and knowing true coolant temp at the fill port is the #1 thing you should focus on.

I'm sure infrared thermometers are awesome, but frankly I've never used one so I'd be a little skittish about trusting one. There's also the possibility of it reading correctly, but perhaps reading other heat passing by from other areas (like exhaust manifold). For that reason I'd want a submerged temp probe (so you know you're reading actual coolant temperature). Digital meat thermometers are cheap, accurate, and fall within the range we're after, so I'd get the van to temp, then (carefully) remove the radiator cap and stick the probe down into the coolant.

Better yet, since you've invested so much in your van, wouldn't you feel better knowing at a glance what the temp is at any given moment? There's lots of nice accurate temp gauges to choose from, but I personally like Koso because they're reasonably priced, accurate, and easy to read:

here's a picture of one installed in my 86 van (blue digits saying 90 deg)

http://i8.photobucket.com/albums/a23/timsrv/TVT%20pics/Fuel%20system/IMG_3654_zps8a015d2b.jpg

Here's a post that gives more info on it and where to buy: http://www.toyotavantech.com/forum/showthread.php?2759-Cooling-system-Mods&p=16143#post16143

[hughdawgmmkay]

Thank you very much Tim! This is so helpful, I really appreciate all the hard work you put into making this post.

I just placed aces an order for the Koso gauge and adapter, so I should have some updates in the coming week!

Thanks again,
Hugh

[hughdawgmmkay]

I'm sure infrared thermometers are awesome, but frankly I've never used one so I'd be a little skittish about trusting one. There's also the possibility of it reading correctly, but perhaps reading other heat passing by from other areas (like exhaust manifold). For that reason I'd want a submerged temp probe (so you know you're reading actual coolant temperature). Digital meat thermometers are cheap, accurate, and fall within the range we're after, so I'd get the van to temp, then (carefully) remove the radiator cap and stick the probe down into the coolant.

Better yet, since you've invested so much in your van, wouldn't you feel better knowing at a glance what the temp is at any given moment? There's lots of nice accurate temp gauges to choose from, but I personally like Koso because they're reasonably priced, accurate, and easy to read:



Alright everyone, the mystery has been SOLVED!

I followed Tim's advice and installed a KOSO temp gauge and found out my van is running 175 - 190! Even after installing an OEM temperature sending unit, my gauge is way off. Looks like I'll be relying on the new gauge instead of my stock gauge.

I can also rest assured that I now have an all new cooling system :). Looks like I'm ready to head to Key West in April for the first major trip.

Thank you all again for the generous help.

-Hugh

[timsrv]

That's awesome :thmbup:

[Gambit]

Quick temp question - I've installed the Koso gauge and all is good while the van is running. But after shutting it off and coming back to it 15 minutes later, I now know how hot it can get AFTER the coolant stops flowing and the engine is off. I've seen it up to 217* before plateauing and very slowly dropping.

Once the engine is back on, it does drop quickly, but is this high temp while off something to be concerned with?

One side effect of this gauge is that I now seem to be hyper aware of my temp at all times!

[timsrv]

This is normal, the only difference being you are now aware. Higher temps while running can create issues due to the dissimilar rate metals expand/contract. When the engine is at rest temperatures are far less critical as there are no moving parts. When started temps quickly drop, so not really an issue there either.

I like this gauge for the same reasons you point out. Always good to be aware of engine temp as overheating is the leading cause of blown head gaskets (not fun). Tim

[trestlehed]

Quick temp question - I've installed the Koso gauge and all is good while the van is running. But after shutting it off and coming back to it 15 minutes later, I now know how hot it can get AFTER the coolant stops flowing and the engine is off. I've seen it up to 217* before plateauing and very slowly dropping.

An easy way to mitigate the "heat bubble" effect is to roll down your front windows and prop open your driver's seat/engine bay lid. I've been doing this for years now, even after all the work on my cooling system has been
completed.

[Gambit]

Great - thanks all! This site is a fantastic resource :silvervan:

[bushcat]

I just want to add that I also had an issue of the stock temperature gauge being off. Mine showed very close to the red at times but when installing the aftermarket temp gauge, it showed normal operating temperature. I'd say the first thing to do is add an aftermarket temp gauge like the Koso before you start addressing other things.