Sludge Hammerin'

[Cogito]

I've been reading info about sludge buildup in engines. Some articles state that sludge is caused in poorly designed engines by extreme internal engine temperatures that may occur in specific areas due to poor lubrication. Or just running an engine at a higher than normal temperature due to a bad thermostat, low engine coolant, etc. Or from heat generated by turbos that is not properly vented. Or from a lot of short trips where the engine does not reach its normal operating temperature before being turned off. This last reason seems to me to fly in the face of the previous ones. I can't envision how sludge could be caused by BOTH extreme heat and also by lack of heat.

The reason I was curious about this is because I ran my Civic for awhile with the "check engine light" on, and the temperature gauge pegged at the top of the scale. This was caused by a faulty O2 sensor. I called my mechanic before driving to his garage and he said just to ignore it. I know the engine got really hot during that trip. Also, I do do a lot of real short trips where the engine really never warms up.

Does anyone know the straight scoop, or can they point me to some definitive accurate data about the cause of sludge? If my engine has some I was thinking about giving it the AutoRX treatment to try to dissolve the stuff. BTW, what is the easiest way for me to determine if it is present? Thanks.

 

[Slick 55]

 

[wavinwayne]

quote:

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Originally posted by Cogito:
....what is the easiest way for me to determine if it [SLUDGE] is present? Thanks.

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Remove the valve cover & visually inspect. Chances are, if your engine has sludge, it will be visible when the valve cover is removed.

 

[Mike242GT]

Cogito: I think I would be more worried about a possible warped head and compromised head gasket from the overheating incident than I would about sludge at this point. A used oil analysis to rule out the presence of coolant in your oil should be your first priority. Then address the sludge issue.

 

[Cogito]

Mike, I don't think there is a head gasket problem as the overheating incident occurred over 2 years ago.

I just peeked into the oil filler hole on the top of the valve cover, and I would guess that there is some sludge or varnish deposits in there. I also saw some on the oil filler cap's breathing vents.

I would like to try to get this crap cleaned out if possible. Is AutoRX my best bet, or is there something else can be added and then drained out after the cleansing period that doesn't take as long to do as the ARX procedure? I only drive this thing about 700 miles/month, and the engine uses about a quart of oil every 700 miles, so if I understand the procedure properly, I would need to continuously keep adding ARX every time I added fresh oil, right? What's my best option for this situation? BTW, the engine has 120K on it, and is a 1989 Civic 4WD wagon with a manual gearbox.

 

[wavinwayne]

Cogito,

ARX, in my opinion, is your best bet at this time. Sorry I can't answer your ARX/oil consumption question, but I do have a question for you. Have you ever changed the pcv valve in this car? If not, I'd say that could be contributing to your oil consumption problem.

 

[m2200b]

Yes you will need to add and you use the ARX to see if you can control that consumption. That just means you will use most of the bottle on one ARX. Your alternative is mechanically redo the engine so I'd start with ARX.


DO you have the blue smoke first startoffs to determine if it value seals since you have a few years here. With that consumption its usually valve seals, rings or pcv system.

 

[BrianWC]

Gasoline in the oil can help compromise it and cause sludge buildup. That is why short trips are bad. If the engine never properly heats up, the gas doesn't evaporate out of the oil.

But yeah, warped head would be my worry right now. Just change the oil while you're at it.

 

[Quest]

IMHO if your mechanic advise you ignore an engine check light and the temp reading gone over the roof, chance are, you have a genuine problem to deal with, and your mech is not capable of finding it out.

Get you mechanical problem resolved quickly w/o delay. The longer you ignore the problem, the worse it's gonna become and eventually you'll ended up shelling out more $$ just to get some silly problems fixed.

Pulling off the valve cover shall reveal to you what the sludge conditions are. Civics are fairly easy on motor oil so long as you change it.

 

[Mr Magoo]

Why would a bad oxygen sensor cause your car to run very hot?

 

[Cogito]

quote:

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Originally posted by Mr Magoo:
Why would a bad oxygen sensor cause your car to run very hot?

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I don't know if this is correct or whether the mechanic was just telling me some **, but he said that the mixture was burning real rich, causing gas fumes to ignite in the CC. I know the CC was red hot though.

 

[Matt_S]

quote:

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Originally posted by Cogito:

quote:

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Originally posted by Mr Magoo:
Why would a bad oxygen sensor cause your car to run very hot?

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I don't know if this is correct or whether the mechanic was just telling me some **, but he said that the mixture was burning real rich, causing gas fumes to ignite in the CC. I know the CC was red hot though.

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A lean mixture will cause an engine to run hot, not rich. A rich mixture will cause it to run cool.

 

[Cogito]

quote:

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Originally posted by wavinwayne:
Have you ever changed the pcv valve in this car? If not, I'd say that could be contributing to your oil consumption problem.

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I have not specifically changed it, unless it was done during one of the scheduled maintenance checkups. How can I tell if it needs replacement?

 

[Cogito]

quote:

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Originally posted by m2200b:
DO you have the blue smoke first startoffs to determine if it value seals since you have a few years here. With that consumption its usually valve seals, rings or pcv system.

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No, I don't notice any smoke. And there are no leaks, so I don't know where the oil is going.