Valve stem seals / blue smoke

[Brett5cent]

Exhaust is putting out blue smoke on startup stops when warmed up. must be valve stem seals i am guessing. how difficult of a job is this on these vans? any tips or things i must know before i get into it?

[blakebecker37130]

Hello,

I also had this issue with my 89.
1. The valve cover needs to be removed.
2. Under the valve cover you will see the rockerarm assembly and pushrods.
3. Unbolt and remove the rocker arm assembly,paying attention to orientation of parts and oil gallery passages. My advice is to lift it out and put it on a piece of cardboard marked front and rear.
4. Remove the push rods, keep these in order as well, there are (8) of them. I marked mine 1-8 and marked them near the top as to remind myself the top-bottom orientation, it is important as these are broken in and wear matched to the rocker arms.
5. You will now see the valve springs that are held in place by valve spring washers and retainers that clip into the valve stems.These have to be removed in order to access the valve stem seals. This is a sensitive operation that needs to be done diligently, so you do not drop a valve stem down into the respective cylinder you are working on top of. I purchased a pneumatic compression tester from harbor freight and used this to pressure up the cylinder, holding the valve stem in place while I pushed down on the valve spring to remove the retainer. A SST or valve spring compressor is utilized to compress the spring and remove the retainers. Once the retainers are removed, the only thing holding the stem up is air pressure. Do not push on the stem and break the compression seal! I learned the hard way to put rubber bands around the valve stems to keep them from falling down into the cylinder. There is also another SST that looks like a socket with a magnet in it. You place this SST on top of the spring and strike it with a dead blow hammer, it pushes the spring down and the magnet grabs the retainers, I did not like that tool as I was concerned that I would slip and bend a valve stem or accidently drop a valve, Which did happen on the last cylinder, luckily it did not fall all the way through the valve head and I was able to get a bicycle spoke into the cylinder through the sparkplug hole and push it back up.

6. Once you remove the valve stem spring washersand retainer clips, you will see the seals. I had to gently pry mine up inorder to get them off. Again be careful not to drop the valve stem into the cylinder.

7. Replace the valve stem seals, check the valve stems for loosness in the valve guides. clean any components that are varnished or covered in sludge, check the rocker arms oil passages to be sure they are not clogged up and reassemble the valve train components. There is also a recommended SST for holding the pushrods in place so they line up with the rocker arms. I made a cardboard template with holes and slits so I could align the pushrods, snug everything down and then pull the template out to the right, I have never had any push rod problems, 5000 milesplus trouble-free so far.

8. There are torque specs for this repair and I recommend a new valve cover gasket kit including the sparkplug tube gaskets and the boltgaskets, the kit should contain all of this suff.

9. Timsrv has detailed info on this job as well, ifyou search the forum for it. There is also a free manual avail if you do an online search that shows the process step by step with SST numbers and torque specs.

10. I had never attempted this repair on any vehicle prior to my van and was a complete newb to the process, I consider myself to be a moderately skilled/tooled technician/driveway mechanic. My personal hardness rating for this repair is a 4 out of 10.

I hope this info helps?

Regards,
Blake

[Brett5cent]

thank you blake, very helpfull. i will report back when i do the job. not jumping into it right away...

[blakebecker37130]

Understood,

You could also try running some heavier viscosity oil to see if it slows the leaking seals down? It wont fix it but might help until you can get to it?

Regards,

Blake

[Brett5cent]

Understood,

You could also try running some heavier viscosity oil to see if it slows the leaking seals down? It wont fix it but might help until you can get to it?

Regards,

Blake how heavy would you recommend blake?

[blakebecker37130]

Hello,

My manual states that 10w40 is the spec oil for most temp ranges. As you may be aware the (W) stands for winter, meaning that when temps are low the oil acts as 10 weight oil, as it is multi viscosity. Once the van warms up to operating temperature the oil acts as 40 weight oil. Do you know if your van is running 10w40? If the oil is old it also has most likely lost some viscosity due to heat and sheering. I have not been following the weather out west but you may be just fine to run 10w40 in your area? I also utilize marvel mystery oil in my gas as well as crankcase. Some say it’s (snake oil), but I have seen it work wonders on removing carbon and sludge from a 1986 Honda cb700sc engine rebuild I did. It freed up stuck oil control rings and stoped the engine from consuming oil as well as reduced the blow-by to next to nothing. Looks like these vans can handle up to 20w50, so no harm in trying different viscosities, just pay attention to the ambient temperature in your area.

4822

Hope this helps. FYI I'm no expert. There are others on this forum who know alot more and have posted thier results. The search function has worked wonders for me, when I have needed quick info to make repairs and adjustments.

Best regards,

Blake

[silverscoot]

Gentlemen, I finally found a friendly mechanic and picked up valve stem seals. We are hoping this replacement will stop the smoking, burning oil...

The mechanic asked me to find out if he can do the job without removing the head. Can he just remove the vacuum hoses and lift the cover to replace the valve stem seals?

I read many a posts but I'm not quite clear about the process and would love to pass him along the right info to get the job done easy and quickly enough.

Will removing the passenger seat help him out too?

thank you for your responses,

Little Bear

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[originalkwyjibo]

Absolutely remove the passenger seat. This is a pretty straightforward job similar to any other engine. If your mechanic is experienced he should be familiar with this. The main difference will be to be extra careful of and prepared to replace/repair the heat damaged parts such as brittle wiring and hoses. Also make sure the grommets around the valve cover studs get replaced as well as the pcv valve and grommet which will likely be hard as a rock. After removing the valve cover, position the piston at bottom dead center with both valves closed and apply air pressure or use the rope method to hold the valves up. Using the appropriate hand wheel type (https://www.amazon.com/OTC-4573-Universal-Overhead-Compressor/dp/B000F5HUUI/ref=pd_sim_263_20?_encoding=UTF8&pd_rd_i=B000F5HUUI&pd_rd_r=RQEQSXS9GCZ8SZVV399P&pd_rd_w=UglwZ&pd_rd_wg=JNobA&psc=1&refRID=RQEQSXS9GCZ8SZVV399P) valve spring compressor remove the keepers, spring, and seal. Reverse the order to install.

[silverscoot]

Absolutely remove the passenger seat. This is a pretty straightforward job similar to any other engine. If your mechanic is experienced he should be familiar with this. The main difference will be to be extra careful of and prepared to replace/repair the heat damaged parts such as brittle wiring and hoses. Also make sure the grommets around the valve cover studs get replaced as well as the pcv valve and grommet which will likely be hard as a rock. After removing the valve cover, position the piston at bottom dead center with both valves closed and apply air pressure or use the rope method to hold the valves up. Using the appropriate hand wheel type (https://www.amazon.com/OTC-4573-Universal-Overhead-Compressor/dp/B000F5HUUI/ref=pd_sim_263_20?_encoding=UTF8&pd_rd_i=B000F5HUUI&pd_rd_r=RQEQSXS9GCZ8SZVV399P&pd_rd_w=UglwZ&pd_rd_wg=JNobA&psc=1&refRID=RQEQSXS9GCZ8SZVV399P) valve spring compressor remove the keepers, spring, and seal. Reverse the order to install.

Thanx for the quick response. Looks like I should order some more parts before he opens up my engine.
For starters, surely everything will be brittle so I should order those grommets around the valve cover studs and the pcv valve and grommet as you suggest. Hopefully someone will chime in with some part #s to order :lol:

So, just removing the cover will give him access and he doesn't have to mess near the head? That's good news if I hear you right. I wonder why this job takes so long? He is estimating between 4 and 8 hours work.

[Hammervan]

In addition to the grommets and gasket, you should count on replacing these two hoses if removing the valve cover: 12262-73010 and 12261-73021. This thread does a great job of showing hoses and their part numbers: http://www.toyotavantech.com/forum/showthread.php?342-Top-End-Rebuild
http://i8.photobucket.com/albums/a23/timsrv/TVT%20pics/Engine/valvecoverhoses.jpg
You will also have to move the power steering return hose out of the way, chances are this is brittle too. #44348-28040, expensive but easily replaced with straight 5/8" hose and some coils to help it bend without kinking.

[silverscoot]

So helpful these links and tips. Thank you. Sure to save us time and dinero too.
Just to be sure, when we say to replace "grommets around the valve cover studs as well as the pcv valve and grommet."

I'd like to order those as well. I'm embarrased having to ask for pictures and part #s but as of yet, I've never been this deep into the engine so there's a learning curve. http://www.toyotavantech.com/forum/images/icons/icon6.png It would be great if my friendly mechanic opened the cover and had all the replacement parts at his fingertips. Thanx for helping me get this all together.http://www.toyotavantech.com/forum/images/icons/icon7.png

[Burntboot]

I always use the rope method (now), takes a little longer but saves pulling the head to retrieve the dropped valve, when the compressor fails to keep up.

That only ever needs to happen once in your life to make you realize the extra 10 mins the rope method takes, is worth every second.

[silverscoot]

I always use the rope method (now), takes a little longer but saves pulling the head to retrieve the dropped valve, when the compressor fails to keep up.

That only ever needs to happen once in your life to make you realize the extra 10 mins the rope method takes, is worth every second.


Precious advice. Use both air and rope! No chances that way at having things fall through.

I looked at many threads and see diagrams for parts. My vaccum hose at the top back of the valve cover is cracked and needs replacing... i posted a photo here just to be sure I am order the right one.

http://livingvideos.weebly.com/toyota-van.html

Is that the part # 12261-73021 as shown in the diagram below?

thanx again

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