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Old 10-02-2002, 01:05 PM
Posts: n/a
Excessive blow-by? Oily mess

About 2 months ago my wagon (diesel) started dripping oil at a much more considerable rate off the cross-member behind oil pan and also started pushing oil out the top of the dipstick tube.

Prior to this, I had none at dipstick tube and just a few drops here and there from the back of engine.

I'm thinking excessive blow-by, but have a few questions regarding this. She still starts, runs, performs very well along with fuel mileage seems unchanged. Also she doesn't smoke that much at all under normal driving down road. I do get some blue smoke upon start-up (which I assumed was leaking valve guide seals) and I get some black smoke under hard acceleration and load.

Things I've checked or done:
1. checked breather hose for clogging or obstruction - clear.
2. checked air filter, rotated orientation as I do get some oil
depositing in air cleaner housing.
3. replaced o-ring on dipstick to try to slow leak down.
4. performed "plugging breather tube test" as described on
this forum. engine shuts down in 2-3 seconds.
5. pulled oil fill cap off while running engine and observed
light but steady vapor puffing upwards from oil in valve
cover, along with tiny droplets of oil being blown out and
landing on top of valve cover.

My confusion is this; if I have worn piston rings and I do have excessive blow-by, shouldn't she be starting hard, running poorer and shouldn't she be blowing blue smoke out the exhaust?

I ran a post last week on the diesel discussion, but didn't come up with a lot of answers. For reference it's called "HELP - oil all over the place".

Would greatly appreciate anyone's help or advice. I am leaking at a rate of 1 qt. in about 250 miles. Prior to this I would typically burn 1 1/4 qts. in a 3000 mile interval, which I thought was good for an engine with almost 300k on.

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Old 10-02-2002, 05:18 PM
Registered Diesel Burner
Join Date: Aug 2001
Location: Northern Virginia
Posts: 2,911
There is a drain tube from the bottom of the air filter housing to the oil pan. Its purpose is to drain the liquid oil separated in the air filter housing down to the oil pan.

If this has somehow shaken loose or gotten disconnected, it makes a pretty big mess. I suspect it might tend to shake loose if the air filter support bracket is broken.

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Old 07-05-2007, 10:36 PM
Registered User
Join Date: Jun 2007
Posts: 183
Can this be replaced with some rubber fuel hose?
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Old 07-05-2007, 10:53 PM
jdc1244's Avatar
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Join Date: Apr 2003
Location: Lakeland, FL
Posts: 170
You need to check the compression, itís the only way to know for sure.

If you have a 61x series engine here are the compression specs:

The service manual indicates an acceptable range of 24 to 30 bar or 348 to 435 psi. Minimum pressure is 15 bar (218 psi) and the allowable difference between cylinders is 3 bar or 43.5 psi.

If the compression is good then you obviously have a leak somewhere.
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Old 07-05-2007, 10:59 PM
Tomguy's Avatar
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Join Date: Aug 2002
Location: near Scranton, PA
Posts: 5,411
Originally Posted by Mattbob View Post
Can this be replaced with some rubber fuel hose?
Your best bet is to make a new thread, asking about your specific issue in Diesel Discussion.

This thread is about 5 years old, the original poster probably won't respond!

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