 too much crank case pressure...., how can you tell? |
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| jr91472 |
  Jul 8 2005, 02:50 PM
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"I'm pacing myself sergeant..."  Group: Members Posts: 1,205 Joined: 2-August 04 From: McKinney, TX Member No.: 2,437  |
So a little history. I am struggling with a rear main seal that doesn't want to stop leaking oil (sounds like I am not the only one).
I am down to two possibilities (that I know of) 1. excessive wear on the flywheel hub 2. excessive case pressure Focusing on #2, how can you determine if there is too much pressure? One mechanic told me that one test is to simply place the oil filler cap on the oil fill neck (without tighting) while the car is idling. If the cap blows off = too much pressure. Anyone heard of this? Ultimately, what is the cause of excessive case pressure? and how do you fix it? sorry for all the newbie questions, but these things keep me awake at nite...... (IMG:http://www.914world.com/bbs2/html/emoticons/beer.gif) |
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| dmenche914 |
Jul 9 2005, 02:29 PM
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Senior Member Group: Members Posts: 1,212 Joined: 27-February 03 From: California Member No.: 366 |
I really seal for you man. that is a bad problem, hope it is not destroying your clutch each time.
The advice on checking for blow-by either from rings, or valve guide wear is good advice. Hope that is not the problem. The flywheel surface that the seal rides on must be mirror smooth, no nicks, scratches, dings, or even deep grooves (from the seal wearing a groove in the fly wheel. Now if you have one small bad spot on the flywheel, you could maybe get away with installing the oil seal not as deep, but it really is best to seat it all the way down, so it is squared up with the crank (I have done this on wheel bearing seals, not on an engine seal) I also use sealant on the seal, add some crankcase half sealant around the oil seal to case joint when you assemble it. you maybe have the leak from the seal / case joint, than from the seal / crank area??? You need to have the case ventalation set up. If you are running stock, you should have a hose from near the oil fil tower that goes to the air cleaner. this set up will actually help pull a vaccum on the case (unless blowby is too excessive). if yo have aftermarket carbs, you will need to rig a ventalatin system hooked to the intake. good luck, and seal you later! |
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Posts in this topic
jr91472 too much crank case pressure.... Jul 8 2005, 02:50 PM
olav Doesn't crank case pressure increase with RPMs... Jul 8 2005, 03:20 PM Jakester I'm far from the resident engine guru around h... Jul 8 2005, 03:31 PM bondo Something as simple as a stuck PCV valve can cause... Jul 8 2005, 03:34 PM jr91472 Jul 9 2005, 09:06 AM Bleyseng sure, take off the oil breather/filler and inspect... Jul 9 2005, 10:09 AM jr91472 <... Jul 9 2005, 10:30 AM jr91472 duh..... http://www.914world.c... Jul 9 2005, 10:53 AM Mueller all motors are going to have crankcase pressure, f... Jul 9 2005, 11:10 AM Dr. Roger Hey JR,
Here's the quick and easy way to see ... Jul 9 2005, 12:55 PM jr91472 Thanks for all the replies people... I really appr... Jul 9 2005, 04:12 PM Dr. Roger Oh, and if I may add another $.01 here....
W... Jul 9 2005, 04:56 PM echocanyons JR,
Could you explain exactly the findings that yo... Jul 9 2005, 05:57 PM jr91472 Basically, the oil is localized to the bell housin... Jul 10 2005, 06:29 PM
scotty b While you're in there check the mating surface... Jul 10 2005, 06:34 PM |
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