Marvel Mystery Oil

[psyolent]

Howdy

Anyone had experience with this product - MMO - or Marvel Mystery Oil - designed additive to 'clean' your engine of sludge and gunk gradually between oil changes?

Always done my changes regularly on my wifes VX and its clean as inside, so no need for it on that. Every 2nd change or so I add an engine oil flush and idle it for 10 mins and then dump the oil out.

In my Holden V8 in my Hilux, it was severely gunked up when i put it in (wrecker motor), I put 2.5L of diesel (yes diesel) in the crank case and ran it at idle for 30 minutes. The usual black came out after running it, but it significantly improved the motor and it runs alot better since. I know this is frowned upon by many people but I did this as an experiment, as, if it didn't work, the engine was coming out for a rebuild anyway (and still will).

My wrecker V6 motor while OK up in the heads, in the valley was very 'crusty' with chunks of coagulated oil in there which i cleaned out as best I could, but am mindful getting it nice and warm and an oil change after its run for 1000km. The oil in the sump is nice and black telling me its not been changed in a while and is good to come out.

Keen on leveraging peoples experience over the years. I've only been here for 42

[vlad01]

open it up and clean it out by hand really good. using oil additive cleaners can and often does dislodge solid clucks that block the oil pickup and cause engine failure.

Also in the oil filter adapter there is a sludge trap int he passages. Take it off and clean it out.

Sump off and clean that out too as well as the pickup. worth replacing the oil pump as engine with crusties in them destroy the oil pump.

[immortality]

It's always a gamble, one that I've played (and lost) it either works reasonably well and you have noticeable improvements or you loosen enough gunk and crap to either block the oil pick up or remove enough crap from critical areas to effect oil pressure.....

I use an engine flush to maintain engines, I once did it on an old 202 and lost all oil pressure at idle once up to running temp however been a trusty Holden donk it continued to provide good motorvation for many a year, the next oil change it got a much thicker grade oil which helped it's cause a little.

[Charlescrown]

Sludge is one of the hardest problems to remove. Avoid the snake oil salesmen promising the world. I have never seen one that really works, many actually end up getting you into trouble with a blocked pickup. The best way is partially dismantle sump tappet covers etc and get a jet blaster in there. If you only are concerned with the oil pickup screen drain the oil put a few litres of thinners in overnight, drain and fill with new oil.

[psyolent]

thanks guys. will pull it off and have a looksee.
sump was coming off anyway for the sump gasket replacement - gotta see if i can get the rubber one from holden.

[VK_3800]

Diesel oil has more detergent in it too, can help clean things up... but like everyone says, once the thing is full of sludge it has to go somewhere and that's usually somewhere you don't want it. Personally if the engine is not of great importance then just run it and don't disturb the sludge, if it is then take the time to clean it out properly.

Holden V8s seem to have a bit of a reputation for building up sludge, but in my experience this is nearly always when someone has messed with the breather system. Engines that run regularly with the right grade of oil and correctly set up PCV systems (which includes at least a vacuum operated valve and a breather, situated correctly in opposite heads) don't build up sludge.

[immortality]

Engine use and servicing plays a big part too. You really need to get the oil up to full working temperature on a regular basis or trouble you will have. It actually takes a fair bit to get the oil up to full operating temp. I had an oil temp gauge on the old VN, unless you were giving it death, the oil temp took a lot longer to reach temp then the engine coolant, sometimes double if not more depending on the type of driving been done.

My old VN didn't get a lot of use, mainly short trips so at least once a month it got a good blast and then a trip up the motorway for a good 1/2 hour to heat everything through and burn off any moisture and contamination that tends to build up in the crank case. Catch can only accumulated a little oil and no moisture (after the intake gaskets were replaced) so I'm going to assume that my system worked reasonably well.

[psyolent]

well the v8 gets regular changes now. and runs great
in other news holy mother of god

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after




big thanks for the suggestion to pull this off and clean it out. might have saved me alot of heartache in the not too distant future
can't wait (i think) to pull the sump off and have a look.

on another note there is a plug at the back (next to the engine mount) which would make a PERFECT feed for a turbo pressure line, but i think it will foul on the engine mount bolt. think.

[Jayme]

haha I should have gotten a photo years ago of my old suzuki G13B engine when I first got it.... its got hollow twin cams, that werent hollow anymore, and sludge the shape of the tappet covers still left on the engine when I removed them

[vlad01]

thanks guys. will pull it off and have a looksee.
sump was coming off anyway for the sump gasket replacement - gotta see if i can get the rubber one from holden.

NLA about 10 years ago. felpro and durapro make rubbers ones though.