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4.3L V-6 noise

OK i'm at my wits end on this one.

I have a 1995 chevrolet G20 van. It's equiped with a 4.3L TBI V-6. I have a knock in the engine that shows up after its warmed up. If i were to describe it, it sounds just like a lifter. I have replaced the lifters ( very $pricey$ i might add, its a roller lifter engine ) with no luck. This engine is equiped with the counter balancer by the way. After doing that, i removed the inspection plate from the transmission, unbolted the torque converter and slid it back out of the way. I fired the engine up and the noise was still there. Next i removed the serpentine belt and fired the engine up and the noise remanined. Fustrated i searched the internet and i came across a GM Technical Service Bulletin that said the exaust valve seals might be starving the guides for oil causing the valves to bind. I went and purchased the updated seals from GM, installed them, and noted no change.

The source of the knock seems like it is coming from the center of the engine. I placed my stethoscope on the timing chain cover and i can hear it. I have heard tales that the noise may be caused by slack between the counter balancer and camshaft gears and supposedly GM knows about this.

Its not a deep knock like a rod or a main and like i said earlier it shows up after the engine is warmed up. The engine runs great, very smooth, has good oil pressure, produces good power throughout the RPM range and it only has 60,000 miles on it. The engine has been treated to regular oil changes.

Thanks in advance!

PMB

Reply to
whizbangmusicwerks1
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Reply to
Shep

I had a simular issue with an 87 dodge truck 318 V8. After replacing rod bearings and oil pump I found the catalatic converter near the exhaust manifold was clogged and making a ticking noise that sounded like a lifter or a light rod knock. Nothing a hack saw and a screwdriver could not remedy. Steve

Shep wrote:

Reply to
71swinger400

thats a very real possibility. heck let me fire it up and take a listen with a stethascope Thanks!

Reply to
pbrady73

========= =========

I've got a lot to say about yer reply...... but.... what's the use aye.....you don't care.

formatting link

To the OP of the thread...... please....... please.... please.....

do the human race a favor..... do not perform the above proceedure on your vehical.

~:~ MarshMonster ~If you can afford a computer, and internet access,........... you can dang well afford to do your part not to fry this world.... so.....sell your puter and fix yer vehical~

ps..... i can live without reading yer posts I can't live without a planet to live on

Reply to
Marsh Monster

don't worry about it! I didn't and i would not have cut the converter out. The stethoscope told me everything i needed to know and for your information thats not where the problem is. The problem is inside of the engine. I would also like to note that i recycle all of my vehicle fluids. I also updated my vintage 1972 chevy pickup with with a modern fuel injected engine and transmission. It went from 8 MPG to 17 MPG in about 2 months and a bit more tweeking will get it in the 20's. And yes there is an ALDL sticking out from underneath its dash panel.

In short, Relax.....

Reply to
pbrady73

======== ======== Sorry...... but not only can I not, but I won't... relax......... untill that particuler suggestion quits being posted as a viable alternative as a repair. It never fails to be posted in the forums by some self-serving, short-term think'n, gonna do fer me first type of individual without even a second thought as to the major contribution they're making to killing me.

Really gits my goat...you know.

any whooo........

you seem to be a very intellegent, logical, caring sort.... so carry on.

and congrats on the gas mileage thing, keep up the good work.

~:~ marshmonster ~rolls him another one...grabs his lighter......time to relax~

Reply to
Marsh Monster

I will offer this, I lived in a state where emission tests were performed annually. During that time I had the opportunity to have a vehicle tested with and without the converter in place. On that particular vehicle emission levels were virtually the same with and without. Additionally, My suggestion is only a temporary means to determine if that is the problem. Further, a faulty (non-functioning) converter is not doing mother earth any favors either. The Big 3 have plenty of other options instead of using a part that is a definite failure item. No matter what every converter made will fail because they are designed that way. I get steamed that we the public don't see anything wrong with purchasing something that could be better but in order to keep selling cars they are made to only last a certain length of time. I not going to go on I think you get the drift. Oh if or when the super volcano known as Yellowstone national park blows you will have a lot more than emissions to worry about.

Reply to
71swinger400

. . ====== ======

I get the drift.

~:~ marsh ~:~

Reply to
Marsh Monster

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