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Topic: Flushing an engine w/o REALLY flushing it (Read 1174 times) previous topic - next topic

Flushing an engine w/o REALLY flushing it

In this case I am talking about my '88 5.0.. the one with the bad ring(s) and 168k miles.. but if this is a fruitful effort, it should be useful for anyone in a similar situation.

Pieces of this debate have been floating around for awhile, but I wanted to finally put them in one place and do something with 'em.

Now, I'm aware that there are various methods out there that claim to be really good at cleaning out the inside of a dirty engine. ATF, etc. I'm also aware that for every claimed method, there's someone else who swears that method is either useless or dangerous.

Whether I'm right or wrong, I am of the opinion that there are some deposits I don't really want to get rid of.. like anything that might have accumulated in any scratches in the cylinder walls, for one example. So all these miracle flushing techniques seem a bit much for me. However, I had the valve covers off to paint them awhile back, and the tops of the heads are covered with black sludge.. everywhere. (I describe it as looking at the inside of a chain-smoker's lungs) Any spot where oil could accumulate had a very nasty semi-liquid form of that sludge in it. I feel I should do something to try to clean it out.

So here's my current line of thinking: A lightweight cheap "dino" oil, like 5w20.. run for however long it takes me to burn off this tank of gas in it now.. (currently 17 gallons) then changed again (w/ new filters each time, of course) to 5w30 or heavier when this thing is ready to go. Does this sound like it should flush anything out that isn't going to move for what's in it now? (I believe it's probably old 10w30.. it's very dark, needs a change soon.. also overfull)

If you don't think that will work, I'm open for suggestions for other moderately-effective (and relatively cheap) flushing methods. Remember, I don't want to go overboard and possibly cause more harm than good. If I were still going to rebuild this sooner rather than later, I'd just do some extreme cleaning method right before rebuild or something.. but now I need to keep this thing going this way for awhile, until the LSC situation is resolved.

Re: Flushing an engine w/o REALLY flushing it

Reply #1 –
Out of personal opinion if I were trying to clean out the engine myself i'd pick up some of that conversion to synthetic liquid (the type that you run in your engine when you want to convert from regular to synthetic oil). That would be a good start with your oil proceedure. The only thing that I could see as a negative is that what you'll end up doing is leaving a lot of deposits at the bottom of your oil pan. Speaking from oil pan replacement experience, I noticed a decent amount of sludge in the bottom of my old pan.
 
 If your 88's engine has as much gunk in it as you allude to then i'd put money on it that you end up with a lot of  in the bottom end of it, and i'd be concerned that you could possibly pick that  back up through the oil pick-up and clog the  outta it. I'm not sure draining it multiple times would help much either (again basing this on what I experienced), there were some decent clumps in that pan. But in all honesty i'd pick up a bottle of that conversion stuff (heck maybe 2) and run that through as well. Overall you ought to be able to get a fair amount out that way. But again, just personal opinion, not fact or gospel. :dunno:
Temporarily Foxless? Ride the Bull...

Re: Flushing an engine w/o REALLY flushing it

Reply #2 –
Really a engine with heavy deposits should NOT be flushed, unless you are going to pull the oil pan(cause it will be full of crud). Just change the oil and filter(use a Motorcraft) and then again after about 500 miles, and don't worry about it...

Re: Flushing an engine w/o REALLY flushing it

Reply #3 –
Totally agree with TurboCoupe50, dont flush it, or you will clog the pick-up. If you have intentions of cleaning the pan, put a quart of automatic transmission fluid in there. It is a high detergent oil and will clean it out quick! It is about a 5 weight oil.

Re: Flushing an engine w/o REALLY flushing it

Reply #4 –
I might consider removing the pan to clean it at some point, since I'll have an engine hoist available in a few weeks. Then again, I might just wait until I am finally ready to rebuild it, and flush it out just prior to that with something like ATF.

Re: Flushing an engine w/o REALLY flushing it

Reply #5 –
Quote from: Bird351
I might just wait until I am finally ready to rebuild it, and flush it out just prior to that with something like ATF.



 You can save yourself a step in that.... If you're gonna rebuild all the junk will come out anyway. Especially if you take the block and heads to be honed/machined. Running something through to clean it before you tear it apart would be one of those un-necessary/extra work/why bother kinda of things. Just my  :2c: :dunno: !!
Temporarily Foxless? Ride the Bull...

Re: Flushing an engine w/o REALLY flushing it

Reply #6 –
Well, if I did have it rebuilt, I would probably drive it over to my friend's house the back way (mostly residential roads.. 40 mph and under) and that's about 5-6 miles. If it isn't horribly unsafe to do so, it's something I could throw in there just before that "final drive".. so it's not a terribly inconvenient thing to do.

Might be better to do something like that (pulling the engine) in his carport or driveway with solid pavement and an engine hoist handy, rather than in my yard with nothing more solid than dirt to work on.