Engine flush?

As many of you know I have an '88 Ford Escort with over 518,500 miles on it. For the first 12 years of it’s life it was used as a work car and was driven on dusty construction sites daily. Even though I performed regular maintenance there’s a considerable amount of sludge in the engine probably where dust entered and mixed with the oil. Last spring I had to remove the oil pan and clean the pick up screen for the first time in the car’s life, because the oil pressure was low. This brought the oil pressure back to normal, but now I’m noticing the oil pressure is dropping below normal again so I assume this sludge is starting to turn loose and is clogging the screen again.

I was wanting to get opinions on whether to use any type of engine flush to help loosen the sludge before removing the oil pan to clean the screen again or just leave it alone. If you suggest a flush tell me what you recommend. My concern is if I use a flush it will continue to loosen the sludge even after I’ve removed the oil pan again and cleaned the pick up tube. Removing the oil pan and cleaning the pan/screen is a several hour job and I don’t want to have to do this every 6 months yet I want to see how many miles I can get out of the car before it wears out.

I’ve used this with success on my old 1985 Buick Skyhawk. http://www.autobarn.net/chmf-3.html

This might be a good choice too. http://www.amazon.com/Gunk-High-Mileage-Motor-Flush/dp/B000AME4V4

However, you have to make sure you follow the instructions precisely, or you could damage your engine. If you’re worried about residual engine flush being left in the engine, you could follow with a second oil change after a short time.

My concern is that the sludge that it doesn’t remove will be saturated with the flush and continue loosening it even after I’ve cleaned everything out again. What do you think?

I say leave good enough alone at a half million miles it does not owe you a thing. With that said, drop the pan to clean off the screen again, and obviously clean the pan as well. You could also remove the valve cover and remove any sludge in the head area… That should be good enough to keep you rolling. I would also invest in a real Oil Pressure gauge at this point (not the gauge on the dash which is what I assume you are using). It will give you a much better idea of what is going on in the motor then the gauge on the dash. Its possible you sender is going bad, or the gauge itself is getting sluggish at this point in its life. Considering most Escorts of that vintage are LONG GONE, anything is possible.

The engine flush treatments look troubling to me. You are apparently doing something right to keep that car running half a million miles. Maybe you should be giving lessons on vehicle maintenance. I would recommend dropping the pan again instead of flushing but I feel somewhat out of line giving you advice on the subject.

It has an aftermarket mechanical pressure gauge that I installed several years ago. The car was originally equipped with an idiot light so I disconnected it and put a gauge in it’s place. I cleaned the pan good last time around that’s why I think the sludge is breaking loose on it’s own. I was really impressed last time I cleaned the screen the oil pressure at highway speed was about 55-60 PSI indicating the bearings were probably still in good condition.

It won’t hurt to add a can of engine flush, any brand. An engine flush is simply a volatile organic solvent like xylene. It will help dissolve some varnish that coats an engine’s interior and may loosen some sludge. It all comes out in the oil change, and any residual is quickly burned off when the engine runs going through the PCV valve.

I don’t know if it will help you any since your problems might not be caused by contamination of any sort or deposits. But a can is cheap and won’t do any harm.

I’m on the ‘don’t mess with a good thing’ side, 500k is the max you can expect, clean the screen again if you want. Put in a mechanical pressure gauge, if it reads ok while driving you’re fine.

@FordMan1959, I think if you use the product correctly, it will break up whatever sludge is in there. If it’s that bad, flush it more than once.

I have no idea if this works…but I knew a guy that would drain the oil…and then fill the oil pan with kerosene (which is basically what Gunk is). Let it sit for a couple of hours…the drain the pan again. Said it cleaned out everything. I’ve done this to an old snow-blower…did a great job cleaning.

I’ve never kept a car over 350k miles before. Never had a problem with sludge so I can’t say from experience on how to remove it. I’m pretty anal about oil changes also…never ever go past the recommended oil change interval…and I use a full synthetic due to the cold winters and my summer towing.

Completely fill the engine with kerosene.
That’s right, fill it right up to the fill hole.
Let it soak overnight. Drain. Fill to the normal level with oil plus a quart of an engine flush or kerosene.
Let it idle for a few minutes, then change the oil and filter.

(I’m only half serious, but let us know what happens if you try this.)

DO NOT FLUSH and engine with that many miles on it…PLEASE… The reasons are too numerous to list.

I know there’s quite a build up on the valve train (can be seen though the oil fill hole) so if I get decent weather for a few days I may pull it into the garage where it will be a bit warmer, pull the valve cover off and clean everything I can by hand, run the flush though it to try to clean the passages, then drop the pan and clean the pan/screen. Just because I said “I MAY” do this it doesn’t mean that’s the approach I’ll take so please keep the ideas and comments coming. If you think it’s a bad idea tell me and tell me why you think it’s a bad idea. I ask this question here, because I know there are several mechanics that frequent this site. How large are the oil passages in an engine? How large a piece of debris would it take to clog them? What’s everyone’s idea of this approach?? I’m not concerned about doing anything that may ruin the engine after all it has already given me great service and the car is in pretty poor condition as far as the body/interior and if it’s damaged we have 6 other cars so this would be a small loss. My main goal is to prevent having to spend several hours dropping and cleaning the pan/screen every few months. I have chronic back pain and spending all day laying on a concrete floor working under a car is not my idea of fun.

I’m glad my wife doesn’t know a car can last that long.

Personally, I wouldn’t bother with it at that mileage. It could well be that the oil pressure loss is due to crankshaft bearing and cam journal wear. At that age and mileage wear has to be a factor.

If you do go so far as to remove the oil pan to clean out any sludge then I would advise removing a few crank bearing caps (fartherest from the oil pump) and inspect the bearing shell in the cap that is removed.
Odds are you will see nothing but copper; meaning it’s worn out. If you’re at that point then throw a new set of rod and main bearings at it while the pan is off.

I’m not a fan of trying to de-sludge an engine because I feel that it may create more problems than it cures.
Caked oil stuck to everything is not going to be a problem except for a few critical areas; the oil pump pickup screen, the bottom of the pan itself, or possibly the inside of an oil galley. Cleaning the galleys out would be near impossible and if a chunk of coked engine oil was dislodged and ended up clogging one of those galleys then you could kiss whatever is affected by that galley good-bye.

ok4450 makes a good point. You could be falling into the trap of assuming your loss of oil pressure is due to sludge, when the cause could be any number of possibilities. However, I believe if you use the “high mileage” engine flush I linked to above, and follow the directions carefully, the chance of damage is minimal.

I tend to agree with ok4450 also. The possibility of shaking a piece of sludge loose from some harmless location and setting it free to get pumped into and plugging a small orifice has kept me from using motor flush other than cleaning up antifreeze contamination.

FordMan: If this were my car I wouldn’t do the flush . . . but I might think about the suggestion of cleaning the top-end by removing the valve cover and giving it a good going over with solvent and then blowing it all clean and dry, followed by a good cleaning of the oil pan and pickup. Blow that clean as well. The flush absolutely will dislodge crud . . . that’s what it’s designed to do . . . and where the crud ends up is anyones guess, but that could go bad for you. I’ve got a senior citizen too (an '89 Accord with 542,000) and I’d never do the flush. Good luck! Rocketman

At 518K miles, the only “flush” that will work is called a “Hot Tank”…24 hours in a boiling sodium hydroxide solution…Don’t put anything aluminum in there…

For aluminum, the Cold Parts Cleaner Tank…