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[ QUOTE="jwthompson21, post: 662808, member: 35223"]
Last Friday, I noticed there was a good sized puddle of oil under my vehicle. I put enough oil back in to make it to a mechanic, and his diagnosis was that the PCV port going through my I6 block is clogged, and the added engine pressure is pushing oil out the main seal where the transmission mates to the block. Should I try using the Sea Foam stuff to free any blockages BEFORE I take this thing to a better mechanic that actually knows what to do with it?
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Your "mechanic " should go back to flipping burgers
You cannot push oil out through the rear main unless it leaks all the time anyway!

Search for my post on how to fix your problem ... I'm tired of reposting it every week.

You can fix it yourself. You CAN!
 

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Ravalli Surfer, member: 377580"]

Did you notice that the OP was FROM 2009? And as hard as it is to see the back of the engine, his leak could have been from the BACK OF THE VALVE COVER and was just assumed as to be a rear main. But it doesn't matter now, since the OP IS OVER 10 YEARS OLD!

PLUS, THERE IS ABSOLUTELY NO REASON FOR YOUR UNACCEPTABLE NAME CALLING ON THIS SITE! This site is to be a safe place for owners to learn about issues and fixes for those issues! After all, we ALL, including YOU were ignorant as to the workings of automobiles at one time in our lives!
 

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I so thoroughly dislike people dispensing mechanical repairs using old wives tales, mystical assumptions, Magic 8 Ball diagnoses and delusional visions that come in the night.

It makes it impossible to be a real mechanic when so many ex-hamburger flippers working in shops of questionable integrity, ethics and experience are telling people downright lies.

Worse yet are those who defend such hooligans and thieves under the guise of being kind. Kindness is not what is needed when bad information is coupled with gang mentality.

There's enough honest work out there to keep people of integrity busy for the foreseeable future and beyond. Mechanical arts should never be staffed by quack mechanical artists!
 

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I so thoroughly dislike people dispensing mechanical repairs using old wives tales, mystical assumptions, Magic 8 Ball diagnoses and delusional visions that come in the night.

It makes it impossible to be a real mechanic when so many ex-hamburger flippers working in shops of questionable integrity, ethics and experience are telling people downright lies.

Worse yet are those who defend such hooligans and thieves under the guise of being kind. Kindness is not what is needed when bad information is coupled with gang mentality.

There's enough honest work out there to keep people of integrity busy for the foreseeable future and beyond. Mechanical arts should never be staffed by quack mechanical artists!
If you are referring to me, I call you on your BS. I have been doing mechanical work on all kinds of equipment for the past 38 years. If it has wheels, engines, electricity, coolant, or refrigerant and isn't ships, airplanes, or trains, I've worked on it or something like it. Worked nearly 10 years on school buses (pre-fuel injection), small engines, a certified electrician, certified Commercial HVACR contractor, Peterbilt/KW/International A/C specialist, as well as factory trained in over-the-road diesel powered refrigerated transport trailers. In my nearly 4 decade work career, there hasn't been much that MY COMPANY hasn't worked on! The only thing that I choose not to work on is transmissions, and that is because I have a great transmission guy that specializes in transmissions and nothing else! Furthermore, I've owned my own business continuously for the past 29 years.

Now, if you are referring to the "backyard mechanic" of the OP from over TEN years ago, we don't know the whole story, and even if the OP was totally correct in his terminology, because there are many people who have vehicles who are so ignorant that they don't even know enough to be even be able to find the hood release lever!
 

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Hmmm.... sorry to see that the cat's got your tongue.

Obviously someone kicked your feed dish - but if the shoe fits, et al............
 

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Hmmm.... sorry to see that the cat's got your tongue.

Obviously someone kicked your feed dish - but if the shoe fits, et al............
No, YOU are not being clear as to whom your replies are referring to, which is not a good sign as to your......
 

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You are 100% correct Mike. When your PCV Port is clogged, instead of there being a vacuum at that clean air line it turns into an oil spitting machine.
 

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When the port stops up, it also makes the plastic valve cover leak all over the place! When you remove the coil packs and check your spark plugs, if you see oil in the spark plug area, before you panic and replace the valve cover orings (wich is a PITA), first remove the oil and clean the port. Many times the silicone orings will stop leaking (or will leak no where near as badly) after cleaning the port, (and you will save time and money as well). IF you change the orings and the port is stopped up (and you don't clean it), the new orings will leak within a very short time!
 

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When the port stops up, it also makes the plastic valve cover leak all over the place! When you remove the coil packs and check your spark plugs, if you see oil in the spark plug area, before you panic and replace the valve cover orings (wich is a PITA), first remove the oil and clean the port. Many times the silicone orings will stop leaking (or will leak no where near as badly) after cleaning the port, (and you will save time and money as well). IF you change the orings and the port is stopped up (and you don't clean it), the new orings will leak within a very short time!
Tnank you TigerMike1
6 HOSE,PCV (DIRTY AIR) (PCV INT MANIFOLD TO CYL HEAD PORT).
PCV DIRTY.jpg



PCV CLEAN.jpg

6 HOSE, PCV (CAM COVER TO AIR CLEANER)
 

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Tnank you TigerMike1
6 HOSE,PCV (DIRTY AIR) (PCV INT MANIFOLD TO CYL HEAD PORT).
View attachment 55397


View attachment 55398
6 HOSE, PCV (CAM COVER TO AIR CLEANER)
Yes, the #6 in the top diagram is the "dirty" hose and has the port in question in the engine where the lower end of the hose is applied. That hose is under vacuum during normal engine operation. The #6 in the bottom diagram is the "clean" hose and supplies fresh, clean air into the cam/valve cover in small amounts in order to "sweep" the contaminants from the engine. As I said, the port is in the fitting where the lower end of the hose in the top picture connects.

Vega, your profile states you're in Russia. I didn't know any TB's were sold over there!
 

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Vega, your profile states you're in Russia. I didn't know any TB's were sold over there!
Yes, this car was on sale.
Just like the Chevrolet Tahoe, Camaro and Cadillac Escalade.
But these are the only car brands sold by official GM dealers.
 

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Yes, this car was on sale.
Just like the Chevrolet Tahoe, Camaro and Cadillac Escalade.
But these are the only car brands sold by official GM dealers.
I bet there aren't a huge number sold over there, so anyone driving a GM product would be easily noticed
 

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Results so far...

The mechanic that diagnosed the problem actually attempted to unclog the port by spraying throttle body cleaner into it. That didn't produce immediate results, but the truck sat for 2 days. After picking up from the mechanic, and driving to and from work with fresh dino 5w-30, there is very little leakage visible. I have inspected the ground under the truck 5 times throughout the day yesterday.

The PCM has picked up on the issue and my 'idiot' pressure gauge is showing a fluctuation of 40 psi at idle, maxing at 60 psi when under 3K+ rpm load.

Being broke at the moment, I can only minimize my drive time to two days a week until I can get some Sea Foam and do a complete oil and filter change. After tax returns, I will be sending the truck to my GM mechanic friend who can then assess the replacement of seals.

Thanks everyone for your input!

JT:bonk:
 

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View attachment 55397
Number 6 - is the CV side of PCV system, and us just a delivery hose.
This is not in itself, to be considered as the control valve - there is no actual 'valve' here --- there are just ports that are metered by the head gasket design further inside the gasket-to-deck/head zone..

View attachment 55398
6 HOSE, PCV KV (CAM COVER TO AIR CLEANER) - this hose is NEVER under pressure but it MAY have a very small amount of vacuum as allowed by the metered port cast into the valve cover.
If this hose leaks any oil, it usually means there is pressure inside the crankcase zone.
____

The small s-shaped hose under the air muffler-plenum thingy (upper photo) is the KV side of the PCV system.
The l-shaped hose on the driver's side of the engine under the ECM is the CV side of the PCV system.

Since inspiration for the PCV system is rather limited by design, you need it to work at 100% capacity.

Filling the steel nipple on the underside of the L-shaped hose will have good results if you let it sit for an appropriate length of time. I however have no idea of what an appropriate length of time would be for YOUR vehicle.

Then blow into the lower pipe with a lot of air pressure (100lbs+) to clean out the gunk that's in there. You may have to repeat this a few times if the neglect has been for a long time and many miles.

You should NEVER have any positive pressure in the engine crankcase, the valve cover(s) and the timing cover.

Under NO times or circumstances may the rear seal leak.
If it leaks, it is on short notice to you that it is in jeopardy and is talking to you now to get your attention.​
 

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Yes Sir guys without taking the value cover off to see what was going on with that port on the top side front of my v6 gmc I put a Philip screwdriver down inside the port and pushed something out of the way my envoy started running much better
 
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