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oil in the intake

Posted: Fri May 10, 2013 11:43 am
by Berry
I' ve got several times oil (a spoon full) in my intake, but the air filter is still clean.
what could be the problem? a broken gasket or what?

your help is appreciated!

Re: oil in the intake

Posted: Fri May 10, 2013 11:58 am
by heavywoody
The PCV valve is bad. On your engine, I believe it's located on the rear valve cover, connects to a hose that goes under the plenum.

Re: oil in the intake

Posted: Fri May 10, 2013 12:05 pm
by 3X00-Modified
Positive crankcase ventilation system, OR the breather tube from the valve cover is sucking in oil vapor from the crankcase as its designed to do, but with engine age and increased blow by you will have the breather system pulling in more vapor which will also bring in this oil. Could just be a sign of a clogged stuck open PCV valve too, so check that first.

You beat me Geoff...

Re: oil in the intake

Posted: Fri May 10, 2013 12:11 pm
by Money pit Beretta
Berry I would replace the PCV valve. It should let blow by gasses out and into the intake, but there should be very little oil. But as the engine wears out there will be more and more blow by. I think your PCV valve is sticking open at around the half way point.
If you don't have the money you can spray carb cleaner into it(after you take it off). Get it all cleaned out and let it air dry until there is no cleaner left(you sure don't want that in your engine). You may be able to use compresed air. The whole point is to get the chunks out.
Really I would just get a new one. Even with your high cost it shouldn't be too much.
Damn, everybody beat me to it.

Re: oil in the intake

Posted: Fri May 10, 2013 12:42 pm
by Money pit Beretta
Hey Berry be careful, that hose that goes to the PCV valve may break off. The one on my 90GT did, all the years of heat an oil made it weak. You will have to take off the upper intake to replace it.

Re: oil in the intake

Posted: Fri May 10, 2013 3:39 pm
by Koots
The PCV system is often overlooked but an incredibly important part to keeping an engine alive.

I've had 3 engines with clogged or improperly functioning PCV systems and if it gets bad enough, could start blowing oil out through seals. Most of the time it just ends up out the valve cover and in the intake tract. If not, it will just expose the next weak point in the oil sealing system. Older vehicles will see it coming out through valve cover and rear main seal mostly, in my experience.

Re: oil in the intake

Posted: Fri May 10, 2013 6:09 pm
by Berry
thank you so much for your fast replies guys
I'ill have a look at the PCV when I'm back from my roadtrip from spain

Re: oil in the intake

Posted: Fri May 10, 2013 6:20 pm
by Koots
I'd love to take a roadtrip to Spain!

If I ever get my GMC K5 Jimmy close to finished, I always wanted to take it around the world. A turbo diesel, 4" lifted, solid axle SUV with enough room for 2 people to sleep in and the capability to run on a variety of fuels...but that's just a dream right now.

Re: oil in the intake

Posted: Fri May 10, 2013 6:36 pm
by Money pit Beretta
You drove from Switzerland to Spain?
Nevermind it's like a 700 mile round trip.

Re: oil in the intake

Posted: Sat May 11, 2013 4:19 am
by weba
I have a shitload of oil in my 3.1 intake hose, it's making puddles to my parking spot at is drains down from the hose (i have CAI just in front of the hood latch), also the filter looks like it gets soaked in oil..

My PCV was good, It' just the blow by in the old engine, and the oversize 3" intake hose with less 'suck' in it.

Re: oil in the intake

Posted: Sat May 11, 2013 5:29 am
by Koots
Correct Weba, there is only so much that the PCV system can do to help. It cannot fix a worn engine, especially if you're got bad valve seals and/or rings.

A catch can setup would help keep that oil out of your system though. It does sound like you'd be draining the can every second day :wink: .

Re: oil in the intake

Posted: Sat May 11, 2013 6:02 am
by Berry
I made this shot yesterday
@ pit: 1000 miles one way.
@ koots: you should really come to spain! and switzerland
@ weba: how many miles has your engine?

Re: oil in the intake

Posted: Sun May 12, 2013 5:35 pm
by Berry
Money pit Beretta wrote:Hey Berry be careful, that hose that goes to the PCV valve may break off. The one on my 90GT did, all the years of heat an oil made it weak. You will have to take off the upper intake to replace it.
if I open the upper intake is there a gasket I should change?

Re: oil in the intake

Posted: Sun May 12, 2013 5:52 pm
by Money pit Beretta
Yeah you are going to have to change the upper gasket and the EGR gasket that sits on the intake. If you have the time get a TB gasket, take the TB off and clean out the EGR port. The one on my 90GT was almost fully clogged at 170,000 miles. Yours may not be to bad, but it is a good idea to check.

Re: oil in the intake

Posted: Tue May 14, 2013 5:51 pm
by Berry
money pit, thanks! I will change the upper intake but do I really need to change the egr gasket?
is it not possible to open the upper intake without to remove the EGR?