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Removing gunk out of the engine?

4K views 37 replies 18 participants last post by  cooljjay 
#1 ·
I was wondering if anyone has any hints on getting the gunk out of an engine?

I have my 78 which was run on wvo, on what I think was a luvcrap conversion and had super tight valves. It sat for probably a combo of 25 years.

I have had it for 2 years, its like night and day in running conditions since I got it.

I have done countless valve adjustments in the 2 years I have owned it and more oil changes then I can even count.

So my problem, is that the oil gets very very thick from all the crap that is in the engine from the wvo, it is very sticky and when I pull the filter they way probably 20lbs. I can tell when its getting thick because the pressure drops a bar on the gauge and then the other day I noticed the oil squirters aren't squirting but rather just dripping.

I also have bad blowby, which I want to change the valve stem seals to see if that cures that....the car starts like a champ and plenty of power.

I have tried running synthetic a couple times too...

So what I am wonder, because I am getting tired of going through so many filters and gals of oil...

Is there anything I can dump in the crank case to help break some of the gunk up before I do another oil change?

There is a local diesel shop, that does an engine flush...its close to 200$ but I was wondering if that is an option, I was also thinking of dumping some mmo into the crank case...
 
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#5 ·
I doubt the diesel flush. I think I'd get about three second opinions on that. I saw the video and think its irresponsible. More importantly, there are very few things that are soluble in diesel. None of the varnishes or carbon or wvo residue will be soluble in diesel. Cheap motor oil would be much safer and will dissolve anything diesel will.
 
#7 ·
Yeh I did some more reading on flushing with diesel fluid....sounds like a great idea but technically its a horrible idea...figured it would be too good to be true.

I even read about using off the shelf engine flushes also are a bad idea as there is a liter of oil left in our cars when we do a oil change and that stuff isn't good to leave in it.

Still would like more ideas and thoughts on mmo....but what the feeling is, is to use synthetic oil but since I have leaks and I am burning oil its impossible to keep synthetic in it...
 
#12 ·
There is not an off the shelf answer for what you are wanting to do.

If you still have the amount of goop coming from your engine as you say, and have changed oil/filters as often as I seem to be hearing, dissolving anything is probably not a viable option right now.

Rather, bulk physical removal would seem to be the task at hand.

If you are beyond that stage, there are no practical solvents available that will rapidly break down the long chain polymers created with wvo use. Nothing magic in mmo in that regard. Think plastic.

Most use organic acids, high heat, or sodium hydroxide to break/clean such residue.

Just think of a very, very dirty and greasy stove.

Best of luck in whatever course of action you choose !
 
#10 ·
Would it be easier to drop the oil pan and scrape out as much of the gunk as possible?
Most of the commercial engine flushes aren't suitable with turbo engines anyway.
Also, at oil change pouring an extra liter of oil through seems to help get those last remnants at an oil change (I don't know if everyone does that but I do).
 
#11 ·
You can flush a gasser...no worries..


To add though, the oil cooler flow rate is probably less than perfect with the sludge issue so removal and a 24 hour soak then flush couldn't hurt freeing it up. Like lay it fittings up and fill to capacity. As for doing an an oil flush, have you tried putting some ATF in the crankcase and run it for like 75-100 miles then drain? This is preferred as it wont harm the bearings like flush ingredients. The detergents in ATF eat up the sludge.

Edit: Just seen what billgrissom wrote so +1
 
#15 ·
Well I'll be a pain in the arse and say the best and safest method is to take the engine to pieces and mechanically clean it - as in scrape it out with your finger nails!
 
#19 ·
#21 ·
The non turbos have a wear oil pump .......to fix the wvo bs after you have done the fuel system if Lubro moly motor flush or GUNK motor flush......those are the only ones i have personally seen to actually make a difference for the better.

I have had it also smooth out ruff and crappy idles and lessen smoke.


Good used injection pump and motor flsuh as many times as you can afford over the next three months like once a money if you have the cash to blow if not once it really good but make sure to just let it IDLE and dont rev it.


If its a neglected motor one can/bottle and 5mins as stated on the bottle. If wvo two bottles if you and and a min of TEN mins.


Just my 2 cents and only based off what i have actually seen. Sorry for the types but in a rush LOL.
 
#22 ·
#26 ·
I'm not sure if you've seen it and I had a hard time finding it on a Google search, but there was a WVO thread on another forum a while back about a guy with a newer TDI who did some half-ass conversion and ran WVO for ~15K miles and then seized his engine. He took it to his mechanic who did a full assembly and there was soap coating everything on the inside. It was ruled to be completely worthless as even a core and IIRC the guy had to pay for a replacement engine. I'll see if I can find the pics -- it was some really gory shit.

Dkr.
 
#28 ·
I think I seen that teardown thread you are talking about, I remember in one of my many arguments on the use of WVO I found a thread that had some gorey photos on it off the valves...

I am looking at your second one....wow amazing, and i am sure that is what mine looks like but probably not as bad, as I've only been burning diesel...this guy seems to have not cared about the damage and kept on going...
 
#29 ·
I'm going to stick with the "open her up and scrape it out" approach.

How did she look when you last did the valves?

Is she your daily driver. because most of this is just time and minimal parts....and then you don't have to worry about leaving diesel/cleaning solvents in there somewhere.......
 
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