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  #1  
Old July 23rd, 2005, 22:24
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Sludge build up

I finally pulled the valve cover off my 180k 87 4.0 mj that I've owned for 6 months and I'm worried about how much sludge buildup it had. Between each set of valves there was up to 1 1/4" of dried brittle sludge, what a mess. I scraped it loose and blew it out of the head with the discharge of my shop vac to keep the pressure low and got it cleaned up really well. My question; is that much buildup and it's dry condition normal for that milage engine or should I be looking for the cause? Any suggestions are appreciated.
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  #2  
Old July 24th, 2005, 04:48
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Re: Sludge build up

an engine should never have sludge build up if running properly. if you haven't taken care of the jeep's maintenance (oil changes) that will cause sludging. also once it starts it just gets worse because it stops the oil from getting into the crank case. I see that you've only had the jeep 6 months so i would assume the previous owner was not very good about doing oil changes.since you've cleaned it up i would start it and see what happens. i would also do oil changes every week or couple a weeks for a month or two to try and help clean out the remaining crap in your engine.
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  #3  
Old July 24th, 2005, 05:45
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Re: Sludge build up

I did mine a few months ago, buildup was 1/4-3/8". I wadded up some pieces of paper towel, to plug up the oil returns, scrapped with the vac going. I even used some picks and very small screwdrivers, trying to get as much as possible.
Moving sludge and carbon around always makes me nervous, anything you miss, usually ends up in the pump screen or worse.
The main cause seems to be cheap oil. Iīve had trucks, that ran synthetic oil there whole lives, the inside of the motor was really clean, when it came time for some head work.
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Old July 24th, 2005, 06:14
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Re: Sludge build up

Mostly from a lack of maintenance. I use regular (natural petroleum) motor oil and do oil changes whenever necessary, I go by the color of the oil, not timewise or mileage. Ive broken down some of my engines after 80 or 90 thou. and the inside always looks new, I really believe regular oil changes are one of the best things you can do for the love of your life! (Jeeps, guys, talkin' about Jeeps)
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Old July 24th, 2005, 13:00
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Re: Sludge build up

I tore down a chevy 350 many years ago that had spent its life on Penzoil. No joke, when the valve covers were pulled you could barely see the rockers etc for the complete buildup of sludge. It literally covered all the valve gear and was just open where the rockers moved. I couldent belive it nor the fact that the oil return holes never plugged off.
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  #6  
Old July 24th, 2005, 13:08
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Re: Sludge build up

Quote:
Originally Posted by dyna
I tore down a chevy 350 many years ago that had spent its life on Penzoil. No joke, when the valve covers were pulled you could barely see the rockers etc for the complete buildup of sludge. It literally covered all the valve gear and was just open where the rockers moved. I couldent belive it nor the fact that the oil return holes never plugged off.
I tore down a Chev. 350 (140,000) that had seen nothing but Mobile 1 itīs whole life, had a bent vlave from sucking some water.
The inside of the valve cover, had a micron thick, covering of slightly discolored oil. Twice a year oil changes.
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  #7  
Old July 24th, 2005, 14:06
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Unhappy Re: Sludge build up

I got it all back together this morning and did a 30 mile test drive; runs good and its a little quieter. I dont think I went more than 5 sec without looking at the oil pressure gauge worried about anything that might have clogged the screen. After seeing how bad the top of the head was I'm pulling the pan tomorrow to do the rear main and replace the oil pump. I wonder how bad the garbage is going to be down at the bottom end?
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Old July 24th, 2005, 16:49
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Re: Sludge build up

Quote:
Originally Posted by dyna
I tore down a chevy 350 many years ago that had spent its life on Penzoil. No joke, when the valve covers were pulled you could barely see the rockers etc for the complete buildup of sludge. It literally covered all the valve gear and was just open where the rockers moved. I couldent belive it nor the fact that the oil return holes never plugged off.
That 350 may have spent it's entire life on Pennzoil, all right--the SAME five quarts.

A modern engine, given regular oil changes, using quality motor oil, should show NO sludge build-up even after 100K+ miles.

Any engine with anything more than a stain on the inside surfaces of the engine is showing evidence of lack of oil changes, or use of poor oils, or both. Period.
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  #9  
Old July 24th, 2005, 18:37
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Re: Sludge build up

Quote:
Originally Posted by AZ Jeff
That 350 may have spent it's entire life on Pennzoil, all right--the SAME five quarts.

A modern engine, given regular oil changes, using quality motor oil, should show NO sludge build-up even after 100K+ miles.

Any engine with anything more than a stain on the inside surfaces of the engine is showing evidence of lack of oil changes, or use of poor oils, or both. Period.
SPOBI, sludge build up is a major problem in almost all the manufacturers engines now, DC, Honda, Ford, GM and Nissan are replacing engines like crazy on new cars because the mentality of 'getting it to market' without proper engine development is causing all kinds of problems, MB, BMW, Vettes, Porsche attacked the problem from the other end and just put syn in theirs out of the factory. Want to totally eliminate sluge, run synthetic, it's high detergent charactistics keep it to a minumum. When my wifes Olds' engine died from a ovheat and warped heads we pulled the valve covers and the inside of that motor was as clean as new but it had only had mobil-1 5w30 in it for it's entire life. I've pulled engines that have had quacker state and penzoil in them, exxon too, that were just plain nasty, the primary difference between the quacker and penz when compared to exxon was the exxon sludge was red...
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  #10  
Old July 25th, 2005, 08:58
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Re: Sludge build up

Quote:
Originally Posted by RichP
SPOBI, sludge build up is a major problem in almost all the manufacturers engines now, DC, Honda, Ford, GM and Nissan are replacing engines like crazy on new cars because the mentality of 'getting it to market' without proper engine development is causing all kinds of problems, ..
Do you have concrete evidence of this? (Tech. bulletins, trade articles, etc?)

I have a couple of friends in the auto tech. training business (they work for Japanese importers, and train US techs from the dealers on diagnosis and repair). They have never reported any such problems, as long as the owner maintained the vehicle per recommended schedules.
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Old July 25th, 2005, 09:43
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Re: Sludge build up

Quote:
Originally Posted by AZ Jeff
Do you have concrete evidence of this? (Tech. bulletins, trade articles, etc?)

I have a couple of friends in the auto tech. training business (they work for Japanese importers, and train US techs from the dealers on diagnosis and repair). They have never reported any such problems, as long as the owner maintained the vehicle per recommended schedules.
Evidence ? do you watch the news, been on all the nitelys for the past two weeks on the major networks 4 or 5 times. Suprised me that they put it on, woulda figured they would have been a bit lower profile seeing as they are sponsors being shown...The interesting thing as the couclusion to all this was that the owner should use the 'extreme conditions' chart vs the normal one.
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Old July 25th, 2005, 09:47
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Re: Sludge build up

Quote:
Originally Posted by RichP
Evidence ? do you watch the news, been on all the nitelys for the past two weeks on the major networks 4 or 5 times. Suprised me that they put it on, woulda figured they would have been a bit lower profile seeing as they are sponsors being shown...The interesting thing as the couclusion to all this was that the owner should use the 'extreme conditions' chart vs the normal one.
To be honest, I have not seen ANY of the newclips you cite.

As far as using the "severe service" versus "normal service" maintenance intervals, those of us in the know pay NO attention to the "normal service" schedules, and ALWAYS follow the "severe service" routine.
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Old July 25th, 2005, 10:44
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Re: Sludge build up

My area of expertise, is taking what the engineers deliver and figuring out how to make it work. At the end of the 70's, I recognized the direction of the scavenger systems in automotive design and promptly switched everything I owned, to synthetic oil. At the beginning of the smog crisis, the manufacturers enacted a pretty much a bandaid approach to engineering. The standards are set by the government and the manufacturers, had to figure out how to meet the standards, as cheaply as possible. The consequences of this engineering appraoch, were secondary.
As far as resume' goes, the guys that designed many of todays motors, where hands on engineers and many of the base designs, have been around for 60 years or more. The original designers, actually didnīt have much of a resume'.
Following the accelerated maintenance schedule, along with normal wear and tear maintenance. Can quickly account for 1/4 to 1/3 rd of the purchase price of your auto, in 7-8 years.
Iīd like to see a study, that accounts for the pollution from manufacturing, as to compared to maintenance costs and vehicle life expectancy. The consumer is often paying, more for less and the manufacturers are pumping them out faster.
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  #14  
Old July 25th, 2005, 11:19
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Re: Sludge build up

http://yotarepair.com/Sludge_Zone.html

http://www.consumeraffairs.com/autom...vw_sludge.html

http://www.syntheticwarehouse.com/Specsheets/audi_engine_sludge_v4.pdf#search='engine%20sludge'

http://www.dontbuyone.org/messages000-199.htm

http://www.autosafety.org/article.php?scid=122&did=961

http://www.wnbc.com/askasa/4700486/detail.html

Want more ???
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  #15  
Old July 25th, 2005, 12:21
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Re: Sludge build up

Interesting.....it appears that German brands are more susceptible to this than most others.

Sludge is NOT a new phenomenon in IC engines. The advent of high detergency oils, more heat-resistant oils, and tighter fitting parts reduced the probability, assuming good maintenance procedures.

I see they note poor crankcase venting as a prime cause. That's not a new invention either, as positive crankcase ventilation has been in use since 1963.

I wonder what else has changed with these engines?
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