The Chrysler Minivan Fan Club Forums banner

Desperate - Rear main again

15K views 40 replies 10 participants last post by  cshoff 
#1 ·
My 2.4L 1999 Plymouth Voyager (has 102k miles) was leaking about 1/2 quart of oil every time I drove it. I properly diagnosed it as a rear main seal and the seal was replaced a month ago. I've driven it about 1000 miles since and now it is leaking again, it appears again from the rear main seal. As a side note, the seal was pushing out with such force that it nearly cut a hole through the ring gear (they called it the flex plate). The ring gear had to be replaced.

I'm kind of desperate to get this fixed. I don't have another 1000 dollars to have a shop change it for me, so I will probably try to do it myself. Obviously the problem appears to be too much oil pressure, but I don't have a clue as to why.

No there isn't too much oil since I have it kept between "full" and "add" on the dipstick.

Thank you kindly for any help you can offer or ideas you can think of.......
David
 
#3 ·
Hi there, definitely not a PCV valve, since that was the first thing I checked for and replaced when this started happening.... Probably a oil passage blockage, but that would sadly require me to pull out the engine and rebuild it.

Anything I can put into my oil to disolve sludge?
 
#4 ·
I would change the oil and in place of the last quart of of oil I swap it out with 1 quart of ATF. The detergents in the atf clean pretty good. Drive it mildly for a 1/2 hour and then Change the oil again. Then refill with synthetic 5/30 and a new filter.

What is the reading on your oil pressure gauge?
 
#5 ·
I don't have an oil pressure gauge on this minivan. (there is only gas, speed, and engine temp) This is as simple of a minivan as they come :-( It just has an idiot light if the oil pressure is too low. Is there somewhere I can hook up an oil pressure gauge? I have the original service manual for a 1998 voyager and it says "remove oil pressure sending unit and install gauge assembly C-3292. Run engine until thermostat opens". But I don't know where that sending unit is......
 
#6 ·
Oil pressure sending unit (or switch in the case of an idiot light) is typically close to the oil filter, when the oil filter is located on the block. It reads the pressure just after the filter in the oiling system.
 
#7 ·
Sounds to me like the oil pump relief is not working for some reason--if its stuck and can't open this might happen
 
#12 ·
That is correct. At idle it wouldn't be high, but at higher rpm's on the highway it could get up there, possibly enough to blow out seals and rupture oil filters!
 
#13 ·
Recommend checking oil pressure at several different locations in
the oil galley system. A large pressure drop at a downstream point may indicate a restriction.

You'd be surprised what can be found in an engine.

Sand, hunks of casting flash, peanuts, cigarette butts, paper, hardened blobs of glue or silicone, etc. Filters only filter whats in the oil pan. Not what may have gotten in during a build or assembly (by mistake or design).


 
#16 ·
I have quite the large amount of tools and have worked on amost all of my cars, but this minivan is new in my fleet and I really haven't troubleshot an engine oil pressure issue before. Where can I check these oil pressures? I don't see much in the manual for where to check the oil pressure.

Thank you for any help.
 
#14 ·
Just a guess, but if your oil pressure was so excessive as to be forcing the rear main seal out of it's boss, then I'd think you would be getting numerous other oil leaks from other areas of the engine. Makes me wonder if the shop you took it to installed the new seal properly. Also makes me wonder why, if they suspected excessive oil pressure was the cause of the original seal being "backed out", they didn't address that problem at the time.
 
#15 ·
I took it to a transmission shop figuring that they would be the quickest to take off the transmission. But that said, they are a transmission shop not a engine shop.

There really isn't much in the way of additional leaks that I see.

So how do you properly replace a rear main seal? Isn't there some kind of glue you can use to make sure it doesn't push out?

Looking at the dealer repair manual, it basically says to just tap in the seal using a special tool that holds the seal equally. It also says to do it dry. I don't know how you could mess that up??

harbor freight has engine jacks for 100 bucks.. such a deal :)
 
#17 ·
2 things,

1. I don't think the oil pump in your van is capable of producing enough pressure in an opening the size of a rear main seal to cut metal.

and 2. Maybe the first shop did a poor job and the seal popped out, or was installed slighlty crooked, or the surface of the crank that it rides on is damaged. (may just need to be cleaned up with a scouring pad, or possibly a speedy sleeve installed)

OK 3 things, I don't think high oil pressure would even cause the seal to start leaking, high crank case pressure yes, but not oil pressure. The only thing I can think of that I have seen from high oil pressure is a ballooned or leaking oil filter.
 
#25 ·
You would have to talk to an enigne machine shop or dealer about the seals/ repair sleeves.

But regarding measuring the oil pressure, you get a mechanical gauge set that contains all the necessary adapters to put the gauge where the stock sensor goes. Then you just run the engine and see what happens.
 
#27 ·
An off the wall thought that came to mind is, maybe (just maybe) you have some "main bearing" slop. That could possibly push a seal out. Simple way to check this would be to get side access to your crank pulley (remove the serpentine belt first). See if you can pull and/or push the crank pulley towards or away from the block. As if you were attempting to pull it out or push it in. Removing the passenger tire will give you access to this side of the engine. If there is "ANY" slop in or out on the crank, then you need a new "thrust" bearing. At that point, you can plan on removing and replacing ALL the bearings (rod and main, since you're in there). Actually, they are very easy to remove and replace, on these engines.

Try these steps and let us know. :thumb:
 
#28 ·
Thank you, that is a fascinating thought, but one that could definitely be in play here. I just have to figure out which one is the right pulley and then get access to it. :) I think this upcoming weekend is minivan day. :)

The thrust bearing is the one behind the rear main seal or that is opposite where the pulley is?
 
#29 ·
Here is a LINK to a inexpensive oil gauge. It will be plenty accurate to tell you what you need to know about your actual oil pressure.

As far as the pulley you need to access to check for end play, it is the main drive pulley at the bottom center of the engine. That pulley is bolted directly to your crankshaft. I've never been into the lower end of a 3.3L Chrysler engine, but I would guess that the thrust bearing is the rear-most bearing in the set (closest to the rear main seal).
 
#30 ·
Thank you! However, I held this gauge in my hand yesterday. What the autozone guy couldn't tell me was the adapter I needed to screw it into the engine to have it adapt up with the pressure sensor. So the brass adapter is what i'm missing. I see a few here that might be of the right size (its large, about 9/16")...

http://www.autozone.com/autozone/ca...0-10&itemId=568-0&store=3247&productId=131456


I also want to thank all of you that have offered help and suggestions, it has been extremely valuable to me :))))))
 
#31 ·
You should be able to find some brass fittings that will allow you to adapt to whatever size compression fittings the gauge comes with at most any hardware store.
 
#32 ·
I have a machinist friend who found that the oil pressure switch is actually a special kind of metric hydraulic thread. Not something that a car part store carries. He was able to acquire something where he works and made me up a gauge.

I'll read the values and then get back to you all.

Again, I truly appreciate all of your help!!!
 
#33 ·
So I have new information:

I took a big screwdriver and torqued on the big pulley at the the bottom of the engine. The only play I was getting was from the pulley slightly warping. I didn't see any play at all from the shaft. So that would imply that it probably isn't the thrust bearing.

Secondly, my friend built me a pressure gauge and I attached it to the engine and when it was cold, the engine oil was running about 60psi. When it warmed up it dropped down to 35. When I rev'ed the engine to about 3000 rpm (I'm guessing since I don't have a tach on this van), the PSI went to about 60psi when warm. it went to about 70psi when it was cold.

So at this point, I guess the rear main must have another issue as to why it is leaking. Does anyone know what to use to glue it in??

I also noticed I have a small leak up at the top of the timing belt housing. I'm assuming one of the cams is leaking a little. But thats for another time when I change the timing belt.

Thanks for any ideas :)
David
 
#36 ·
Your oil pressure sounds perfectly normal. I'd bet 10 to 1 that the problem you are having is due to either a defective seal (made poorly/incorrectly), improper installation, or a groove worn on the crank journal thus requiring a offset lipped seal to properly seal it. You should not have to "glue it in" to get it to seal properly and stay in it's boss.
 
#34 ·
The 2.4L has a timing "chain", that is usually good for around 300kmiles.

The "Thrust Bearing" is usually the middle "Main Bearing" inside the block.

You attempted to "pull" the pulley, but did you try to "push" it ?

Might be better, pending miles, that you consider getting another engine from a recycler or such.

3M makes a yellow glue that my Dad used to use on seals. Be careful, though, it gets all over everything, including your hands. :jpshakehe
 
#35 ·
Actually, the 2.4L is a Dual Overhead Cam configuration that uses a serpentine-style timing belt. Recommended changer intervals are at somewhere around 90,000 miles, IIRC. They are kinda a PITA to change.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top