Leaky Seals and Gaskets - The Saga of Njordi

[Boerderij_Kabouter]

Now that Njordi is running smoothly, it is time to address the soggy bottom.


After inspecting the undercarriage up on the lift, here is my task list:

1. replace front main seal (Part No. 90311-48014)
2. Replace valve cover gasket #1 (Part No. 11213-76020 and Toyota FIPG)
3. Replace valve cover gasket #2 (Part No. 11214-76010)
4. Replace manual transmission select level oil seal (33205A)

Local Toyota parts department should have them all for me next week. Then it will be time to run a 505 CRO oil treatment, swap gaskets, and flush/replace fluids (oil, coolant, transmission, rear diff.).

Hopefully this will get me mechanically at 100% and I can start looking to fun stuff!

[Boerderij_Kabouter]

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This figure shows the transmission seals. The select outer level oil seal is seeping a bit and I want to replace it before I change the tranny oil. I don't think these seals have a part number (which is weird) but the guy at my local Toyota parts department was able to find it with me on the phone. Should come in with the rest of my gaskets and FIPG early next week.

This is the transmission oil I ordered (Red Line 50304 MT-90 75W-90 GL-4 Manual Transmission and Transaxle Lubricant).

[Previologist]

I had to look up why you listed 2 valve cover gaskets, as I've only ever seen one! But they do call it that, which I find weird. The 11214 gasket isn't likely to leak oil though, I don't think. I've never replaced one of those when replacing my valve cover gasket but to each their own.

[John Kaufmann]

Now that Njordi is running smoothly, it is time to address the soggy bottom. ... Then it will be time to run a 505 CRO oil treatment ...

FWIW, I also never replaced the outer valve cover gasket. More important, though: Where did you learn about 505 CRO (which sounds interesting)? Any experience with it? - if so, on what?

[Boerderij_Kabouter]

Learned about the 505 additive from Scotty Kilmers YouTube vids. Seems worth a shot. He got better results with it than other products when checking before and after with a scope.

[Boerderij_Kabouter]

I am about ready to replace my valve cover gasket. I have been reviewing threads and youtube videos for tips and pitfalls and it seems like a good number of folks are adding a full skim coat of silicone or FIPG on the block side all the way around the gasket interface. Is this really a good idea?! The engineer in me screams that following the OEM recommendations from the factory repair manual is the best practice. But I also trust experience in a vehicle that has been repaired by folks for over 30 years.

Would love to hear if the community has a best practice for replacing this gasket. Without strong opinions, I am likely just applying FIPG in the 6 spots indicated in the manual and not adding a full skim layer.

[John Kaufmann]

... it seems like a good number of folks are adding a full skim coat of silicone or FIPG on the block side all the way around the gasket interface. Is this really a good idea?!

No.

... Without strong opinions, I am likely just applying FIPG in the 6 spots indicated in the manual and not adding a full skim layer.

Absolutely. FWIW, I used so little that I still have a mostly-full tube of Toyota FIPG.

[Boerderij_Kabouter]

Changed out the valve cover gasket today. The seal was cracked in several places and clearly seeping at the lower corner int he typical spot. Fully hardened and brittle. The spark plug gaskets were even worse. I am surprised Njordi wasn't leaking more to be honest. Gasket change out was really easy. Access is easy, cleaning the surfaces is easy. Just a routine job all around. Valve train looked really clean to me! Globbed in the FIPG in the 6 spots called for, and tightened everything up in two stages in the specified order. The torque on those bolts is a shockingly low 7.8Nm. Can't believe it is that light, but I checked both the Factory Service Manual and the Chilton and that is what they call for. If that is an important spec, I bet a lot of people are overtightening that connection and the gasket is getting deformed.

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I also swapped out the spark plug wires and changed the plugs... only to find that one of the plugs had a thread insert that was never properly secured. Sooooo I am again off to the parts store for a new insert and some orange thread lock. Still crossing hte fingers I can fire it up tomorrow afternoon with a few things checked off my list.

[Boerderij_Kabouter]

Cracked the PCV hose when reinstalling... another piece of old rubber getting replaced. Part No. 12261-76010.

I popped a new spark plug repair sleeve in there with some red threadlocker and torqued to 25 Nm. So fingers crossed that it holds. Definitely not a quality repair, but this was the least invasive fix I could think of since the "damage" was already done and the repair was attempted with the cheapo sleeve. If this fails I will have to get one of the professional kits and do it properly with an oversize drill out. Hopefully I do not have to go there.

I am going to give the threadlocker a bit to set, connect a temporary PVC hose until the OEM shows up, and get this fired up this afternoon.

[Boerderij_Kabouter]

Test drive was a success! So I once again have a functional Previa. Njordi rides again!!! Idle levels out at 700 rpm once warm, and it is running smoothly through the power band. Feeling much better now.Hoping to replace the front main seal and the transmission seals this weekend. With some luck, my leaks will be fixed and I can move on to non-critical fixes.

[Boerderij_Kabouter]

I decided to just change out the PCV valve and grommet too while I am at it because they are cheap. PCV valve tube (12261-76010), PCV valve (12204-15022), and grommet (90480-18001).Also recently learned that the coolant is supposed to be changed in the Previa every 30k miles. So I just ordered this stuff to change out the coolant. Toyota Red coolant (00272-1LLAC) - 12.3 qt - thermostat (90916-03120) and gasket (16325-62010).My parents have a heated garage space but it is currently full, so I think my next round of work is going to have to wait a week or so until that space opens back up. it is cold here in WI and working in a nice heated space is pure luxury.

[Previologist]

I think Toyota recommends pink these days. It lasts longer than red, not sure what is any other significant differences there are other than the concentration

[Boerderij_Kabouter]

Coolant is a right pain in the butt to get bled fully on this rig. I would say accessing the engine bleeder valve is a must and I am still working on getting the last liter of distilled water in there. But side project finished! I built some wheel cribs to hold the Previa. Works amazing with my 24" lift jack.

[John Kaufmann]

... side project finished! I built some wheel cribs to hold the Previa. Works amazing with my 24" lift jack.

This is new to me - interesting alternative to jackstands. Are they pinned in layers for variable height?

[Boerderij_Kabouter]

Yeah! Each of the base and the middle layer have a framing strap in place to stop any movement. I updated my drawings to show it better. They worked really well and I felt a million times better wrenching around under there. Njordi is stock suspension and wheel size, so it was easy to jack the rear up to the full height in one go. For the front I jacked up, put in the cribs at the shorter setting. Then rejacked with a 4x4 on the jack head and got everything up to full height. Took maybe 15 minutes and I have about 22" of clearance under the van for easy working. The cut list is shown in that first image I uploaded. You need 16ea. 8' 2x4's, 2ea. 8' 2x6's, 16ea. 18" straps, a big box of 2.5" screws or some pneumatic nails, and some wood glue. Cost me about $90 total.

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[13ozLatte]

I did a similar thing when I changed my engine. I grabbed some old 2x4 lumber from a house that was torn down nearby, and made stands by screwing 2x4s together, crisscrossing each layer like a hashtag. I made 1 for each wheel so the van was "parked" way up off the ground. An additional 2x4 piece screwed down in front and behind the wheels ensured nothing could roll away. It was stable, out of the way, and made the job so much easier.

[Boerderij_Kabouter]

I can now confirm that you need to remove the shift lever shaft housing to change the oil seals. And also that the boot on top is likely to be destroyed. So if you have leaks here, you will need both seals, the housing gasket, and the boot. Everything looks like it is in great shape in my van though. One more leak eliminated and transmission oil changed.

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