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ryan roopnarine
12-02-2006, 08:25 AM
perhaps some of you remember me posting about a chevy 3.4l that lost a intake manifold gasket and gargled some coolant for a bit. the first Oil change had some metal in it, so i've been changing it every 1k miles or so. very light sludge continues to come out of it. last weekend, i changed the oil (it takes about 4 quarts) with 10w30 and replaced one of the quarts with 15w40 diesel oil (i don't care if it doesn't "clean" by itself, i just want it to hold the sludge in suspension). replaced with purolator oil filter and drove about 30 miles that day. no problems......(JIC, i don't usually give it a full crankcase of oil. if 4 bottles puts it to 1/4 or 1/2 above min on the dipstick, i don't bother adding any more because i change the oil so much that i don't want to waste it). i "thought" i heard piston slap in the motor the day before the oil change. anyone want to tell me what piston slap sounds like, just so i'm sure? at any rate, my mother calls me and tells me that her husband said that the engine is now knocking (she says you can't hear it from inside the car). he might be hearing the same "slap" i though i was. they aren't driving the car anywhere, and i can't get a straight answer from anybody as to how much oil is in the crankcase right now. i'll be man enough to admit it if i didn't tighten the sump bolt enough, or left a filter gasket on there, causing it to lose oil, but:

1. nobody can tell me how much oil is in there right now
2. nobody has bothered to check the carport floor for leaks
3. i drove the thing for 30 miles the night of the change...no weird noises,

Ross
12-02-2006, 10:37 AM
If there was metal in the oil at the change, it's had coolant mixed with the oil and it was sludged to start with chances are the filter isn't your problem.
About the only "defect" a filter could have would be contamination or leakage.
Souds like a tired neglected motor to me.

Derek A.
12-02-2006, 11:12 AM
These motors are notorious for chewing up bearings - when the gasket lets loose. Chances are the lower in is pretty much shot. Not sure if you can get away with a crank kit or not.

Ross
12-02-2006, 11:15 AM
Is this the small block Chev with two cyls. lopped of and split crank journals?

632 Regal
12-02-2006, 12:54 PM
check the glovebox, they usually ship with a full set of bearings from the factory.

A piston sound is similar to a rod bearing (a little higher sound), these are also famous for the piston pins to get loose too.

632 Regal
12-02-2006, 12:57 PM
after reading your multipost, why cant anyone even check the damn oil level?

ryan roopnarine
12-02-2006, 09:52 PM
unfortunately, the mod kept the wrong post. what this all comes out to is that they've already rested the blame on my shoulders for this, since i was the last one to "do" anything to the car--they won't say it to my face, however. i really don't feel like doing a damn thing to this car, but i don't want it to sit there for months or years if it has bought the farm.

some background:

car is 2001 chevy impala. was a company car for the current owner, who changed oil when the oil life monitor told him to. fleet paid for maintainence, so it really wasn't neglected. i suspect what happened was that a FI or something was leaking a lot of fuel into the motor over many years, causing the sludge that i see now. oil change clowns don't care, so nobody ever told him there was anything wrong. i strongly suspect that the chevy dealership that did the manifold gasket didn't bother to change the oil afterwards, and it may have run with dirty oil for 6 months or so. i was hoping that maybe i could get away with a pan drop and con rod bearing swap if i had to intervene? how hard would that or a con rod/main bearing swap be with the thing in the car? thanks.

Ross
12-03-2006, 02:24 AM
From what I can see you shouldn't be responsible. Explaining this to someone who doesn't get it is going to be hard I'll guess.
Maybe remind the owner there was metal in the oil before.
You might get lucky with just bearings if things haven't gotten too bad.
A leaking FI won't cause sludge, it'll just wash down that particular cylinder and dilute the oil.

BillionPa
12-03-2006, 03:11 AM
the oil life monitor is a warning measure. you should change the oil at a proper interval, the monitor is to warn you when you are past due.

doing 1K intervals wont do much to reduce sludge. you need to actually clean it out. if there is visible sludge under the oil cap then you need to remove it. Auto-RX and LC20 are good desludgers that tend not to be so harsh on the engine. engine flush additives that you idle the car with before the oil change can cause issues.

if there isnt visible sludge, change to a 5W40 synthetic oil and run 3000 mile changes, and throw a bottle of valvoline synpower oil treatment in to reduce piston slap. fill the crankcase to mid point, do a 20 min drive, check the level and fill as necessary.

as ross said, fuel dilution wont cause sludge, it will actually remove it! but at the same time cause excessive wear to the metal components as it washes the oil off.

ryan roopnarine
12-03-2006, 06:28 AM
i guess if fuel dilution doesn't cause sludge, then so be it. there is, however, a big fuel dilution problem coming from somewhere, as the oil smells of gas within 500-1000mi after an oil change. its not heavy "sludge", its just that i can see the valvetrain is dark brown, and if you leave the oil filter off the fitting for a little while (like 20-30 minutes), a brown "nesquick" or "hershey's" chocolate milk powdered looking substance will begin to drip down from it.

ps...i just went to the gm owner's piston slap page (www.pistonslap.com (http://www.pistonslap.com)) (hehehe, gm engines, built "like a knock"). i've forgotten what the car sounded like, but with the wav file there, at least i have the reference for the next time i visit home. i'm going to see if any places in orlando offer the BG oil system flush, and tell the guy to take the car there before i do anything else for it.

Atl530i
12-03-2006, 05:01 PM
That sucks. Such a new model car too.

632 Regal
12-03-2006, 05:18 PM
Ryan, whatever you do DO NOT FLUSH IT! Real amounts of sludge are caused from Dino oil when the car is ran enough to warm up and then shut off, like a very short trip to work.

My Grandfather was of the old school (remember OLD) and insisted of me or my dad coming over at least once a week and warming the car. After he died we got the car, was SOO sludged I had to pull the intake cause the oil wasnt draining into the pan except overnight.

After that I used a motor flush and all the loose crap clogged the oil pickup and ratted the bearings. I pulled the pan to clean the pickup but at that time I didnt know it wasted all the bearings.

If this isn't some sort of relative (which I'm assuming it's someone of importance) I would walk away because YOU didnt cause the damage and it's not your problem. But if I assume correctly you need to clear your head of this problem.

I do not think your going to have fun even if you change the bearings because the entire thing is living in sludgeville, rinse repeat. The sludge needs to dissapeer before you do much of anything.

The bearing job is a 3-4 hour job, not hard with the crank seal the tricky part especially since it's most likely the 1 piece seal :D

Another reason not to use Dino at long intervals especially on short trips.

BillionPa
12-03-2006, 08:48 PM
massive fuel dilution could be caused by a failed injector or pressure regulator (you would know if that happened), failed piston rings, severe corrosion to the cylinders, or negative pressure in the crank case.

either way the car is running rich to cause that, and that problem needs to be fixed #1 priority.

ryan roopnarine
12-04-2006, 05:28 PM
how'd you suggest i remove the buildup then? i assumed that the bg way was the gentlest oil flushing machine/chemical that anyone had for doing that.


Ryan, whatever you do DO NOT FLUSH IT! Real amounts of sludge are caused from Dino oil when the car is ran enough to warm up and then shut off, like a very short trip to work.

My Grandfather was of the old school (remember OLD) and insisted of me or my dad coming over at least once a week and warming the car. After he died we got the car, was SOO sludged I had to pull the intake cause the oil wasnt draining into the pan except overnight.

After that I used a motor flush and all the loose crap clogged the oil pickup and ratted the bearings. I pulled the pan to clean the pickup but at that time I didnt know it wasted all the bearings.

If this isn't some sort of relative (which I'm assuming it's someone of importance) I would walk away because YOU didnt cause the damage and it's not your problem. But if I assume correctly you need to clear your head of this problem.

I do not think your going to have fun even if you change the bearings because the entire thing is living in sludgeville, rinse repeat. The sludge needs to dissapeer before you do much of anything.

The bearing job is a 3-4 hour job, not hard with the crank seal the tricky part especially since it's most likely the 1 piece seal :D

Another reason not to use Dino at long intervals especially on short trips.

ryan roopnarine
12-05-2006, 11:37 AM
arrgh.

the guy has finally come around to believing that the engine was going to do this eventually, and that my changing the oil every 2 weeks was to prevent this. if i were him, i'd be sooo incredibly pissed right now. GM designed a f'd up gasket. gm re-engineers gasket. gm should have the market cornered on fixing the problem so that no callback occurs. gentleman takes car to DEALER with the hopes that they are best qualified to fix "congenital GM" defect. dealer performs fix, but doesn't change oil (what it looks like happened right now). if it were an indy, i could almost, ALMOST shrug off them not changing the oil in it. they aren't gm, they aren't in the business of protecting GM's reputation. i mean, how many mechanics will do a headgasket for you and not FORCE you to pay for an oil change before they re-release the vehicle to you? if this were my vehicle, i wouldn't even have the time to be typing this message, i'd be busy drafting a civil lawsuit against the chevy dealership right now.

if one of these three situations occured, i'll eat an index card off my desk, and begin calling around to see who sells clevite 77 blah blah blah...

1. the oil change was offered for extra, but was declined by the owner/fleet service company.

2. the fleet service company declined to pay for an oil change to accompany the procedure.

3. the dealer told the owner that he didn't have to have the oil changed, but not doing so would void the warranty for the repair.

as far as the facts i have right now are concerned, nobody told the owner that he needed the oil changed afterwards, and no oil or oil filter is reflected on the receipt for the intake gasket replacement, so it wasn't done. he drove around for at least 4 months/2k miles with antifreeze oil

sooo agitated.

Ross
12-05-2006, 11:45 AM
Yep, that's why she's knocking. Gas is a lousy lubricant.
I wouldn't desludge it either, let it work it's way out slowly if it lives long enough.
How did you get stuck on this heap?