Main seal question.

[funguseater]

Hi all...

Well it appears that my front and rear main seals may have blown. I don't know really how or why, but my poor Tercel is bleeding oil from behind the timing belt and it looks like so much oil has sprayed around the motor that it is coming through the passenger firewall carpet. The car really needs the vac lines fixed (leaky)(not routed right) and the timing but the seals come first right.

I should say that the car has 450k km on it but the body is in mostly good shape (cept fenders, easy fix) and when I compression test the motor even with the oil leak I still read between 178-180 psi per cylinder. And the previous owner did rebuild the engine at around 350k km. I have read the FSM many times but would like some opinions on whether this is a repair I should try at home, my background is electronics and I am used to working with tiny components and long tedious component assemblies, has any one on here written a tutorial for this with pictures? I like the FSM but it assumes you have more tools /mechanical knowledge than I may have.

Have any of you tried replacing your seals or could point me to a sticky, (and yes I have tried the search function thank you).

Dave

[Highlander]

Hey Dave, Logbear did a write up on replacing the timing belt in '05. this will take you down to within 2 steps of removing the front seal (After you remove the timing gear from the crankshaft, pry the woodruff key out with a small screwdriver (one that you don't mind sacrificing), remove the slinger and the front main seal is right in front of you. I slid the same small screwdriver under the lip and gently pried the seal out. remember to put some sealant (form-a-gasket #2 works well) around the outside of the seal before tapping it in gently until flush with the surface of the oil pump (where the seal sits). Reassembly is reverse of disassembly, use a new timing belt, and check the tensioner (it should spin fairly freely and noiselessly), align the marks per the FSM and you're good to go.
The only special tools you need are a 19mm (3/4") socket, a large breaker bar and a steering wheel puller (all of which might be loaned out by certain auto parts stores). I've done timing belts in the middle of a parking lot when I ripped mine out before.
The hardest thing is getting the front crank pulley nut broken loose- I always support my breaker bar on a block of wood that lays on the inner fender well, and then bump the starter-that's always worked for me-torquing it properly without a torque wrench is tough though. If you don't have one, tighten it as much as possible, reassemble it, take your 19mm socket with you to a loaner-type parts store-borrow the torque wrench, go outside, put the tranny in 5th with the handbrake on ,and torque the bolt down. return the torque wrench. Done. Then you've dealt with the front seal AND the timing belt issues all at once.
YMMV

[Petros]

IT is unusual to have both seals go out after it was overhauled not so long ago. Sometimes too much crank case pressure can cause the seals to blow out, even new ones. I have seen it before. This could come from a backed up crank case ventilation system (see the FSM for proper function and check valve test), or your rings are worn and causing too much blow-by.

Replacing the seal is not too bad a job, Highlander gave you excellent instructions, and we are always here to help you with it as well. It will be interesting to hear your report of the condition of the seal when you get it out. If it is out of place (pushed forward) but is otherwise in good condition, you have high crank case pressure. If the seal is old, brittle and cracked, than you just need a new seal.

IT seems foolish to have the engine out and not replace the seals, especially the rear main since it is so hard get at when the engine is in place. But anything is possible.

Let us know what you find.

Good luck

[takza]

If you fix the PCV issue...maybe the oil blowby will be reduced? Should never let stuff like the PCV and vac tubing go without trying to fix them?

[funguseater]

Thanks for the info guys, When I started stripping down the motor I noticed the Air filter was soaked with oil, but the PCV valve apeared to be working, I put a new one on anyway. I couldn't seem to get the Cam bolt loose even with a breaker bar so I just re-torqued all the visible bolts (most were waaay loose) and oil leak seems to have stopped. At least now I can still drive wile I await my gasket set. Thanks.

[takza]

I used to have that oil blowback on the filter until I started using PCV jars ...this lengthens the tubing so the oil doesn't get back to the intake and also collects a lot of it in the jar.

[keith]

If you have oil on the air filter and the PCV valve is working, then you have so much blowby that you are overwhelming the PCV valve and oil is being forced out the air supply hose. I know your compression seem good, but I've had a few engines that had good compression but still had excessive blowby.

[4wdchico]

I used to have that oil blowback on the filter until I started using PCV jars ...this lengthens the tubing so the oil doesn't get back to the intake and also collects a lot of it in the jar.

So you are using a jar on the fresh air side of the PCV system? You also have another in the PCV valve to intake manifold line?

I have a small Home Depot air compressor vapor remover/ filter between the PVC valve and the intake manifold. It seems to work fine, it does not catch much oil but there is zero oil inside the line on it's outlet side. Still need a catch can on the fresh air side.

OP: I agree w/ Keith as I have owned a couple of cars that had good compression but also had excessive blowby. This odd situation can be caused by gummed up oil rings and the engine might not be worn out. Not uncommon at all for old Toyotas to last long enough for the rings to get way gummed up. It may be possible to free up those oil rings with a proper ring pack cleaning such as a Seafoam soak.

[garyfish]

I used to have that oil blowback on the filter until I started using PCV jars ...this lengthens the tubing so the oil doesn't get back to the intake and also collects a lot of it in the jar.

I've been running a PCV jar for a little over a year, and that eliminated the previous condition of excessive oil inside my air cleaner. The engine seems to run more smoothly and -- judging by the volume of gunk trapped by the PCV jar -- it's probably running cleaner as well.

http://www.tercel4wd.com/forums/viewtop ... f=4&t=3852

Mine's like the one pictured here:
http://www.tercel4wd.com/forums/viewtop ... 824#p30824

There's a bunch of 'em available on eBay, in various styles & sizes, for as little as $20 or so. Use these search terms on eBay: oil catch can


Sorry to hijack... now back to your regularly scheduled thread

[takza]

You can make one for next to nothing from a pint jar...punch/drill 2 snug fitting holes in the lid...use some 3/8" fuel line to place it out away from the engine. The line leaving the jar should stop right near the lid...the one from the PCV can extend down into the jar some. Main thing is have no vac leaks. The claim with the Condensators is that having a 3-4' hose coming from the Condensator allows the vapors to form a combustible mix that improves mileage.

[Petros]

Putting some kind of oil catch tank might be a reasonable temp solution, but it is far better to diagnose what the real problem is and fix it. The PVC system should run best when it is running the way the manufacturer intended. Adding a catch tank of some kind might be just covering up a more serious long term problem.

I recommend finding out why there is oil getting in the PVC system, and fixing it. BTW, do not assume the PVC valve is good just because it has recently been replaced. And the valve is only one part of the whole system, so it could be something else that is wrong.

Good luck.

[4wdchico]

My oil mist issues began when I replaced my valve cover because the two 6mm bolts that hold down the air cleaner assy seized and broke off in it. Before that, I never had any oil in either side of the pcv system, my pcv valve was free of oil after many thousand miles of driving. I found that pretty unusual. My original valve cover had some fiber mesh looking material up in the pcv system's inlet/outlet chambers on it's top. i suppose that all of the blowby oil mist was caught by the mesh and dripped back into the engine. Pretty good design. The replacement vc was from a very high mileage jy car and has no mesh left in it, especially alter a friend gave it three rides in his parts washer for me.

I have a WOT ping issue that I have diagnosed as caused by oil mist back flowing thru the pcv fresh air intake line at WOT. If I allow the pcv system to back flow to the atmosphere, instead of the air cleaner, at WOT the ping goes away.

I am going with the two catch can system because I prefer to catch and dispose of any oil that is contaminated with blowby gasses. Sure, I could just pull the vc, bend down the sheet metal tabs and insert some mesh up in the the two pcv chambers.

[xirdneh]

I've never seen any mesh screen in a tercel valve cover. The only time i had oil getting into the air cleaner was when there was too much oil in the car. It was burping oil out of the valve cover but not thru the PVC opening, it was the opening just aft of the PCV valve, air vent? or whatever it is that connects to air filter shroud.

[takza]

Think the problem exists because there is a short distance from the valve cover to the air intake point...the PCV system only moves a small amount of gases and they are pulsing in both directions...an older engine also has more blowby?