Marvel Mystery Oil - any experiences? - PeachParts Mercedes-Benz Forum

SCOTTFISH · #1 05-07-2004, 02:17 PM

I have a 90 420sel with 121k on the clock and all of a sudden I developed a rather disturbing lifter noise upon replacing plugs/wires/dist cap & rotor. I think there was a little bit of chatter all along from 100k when I bought the car to present, but now seems to be much worse. I have had the cam checked out and have a timing chain job done about 6-8 months ago. I have gone by many recommendations to go with 15w50 mobil 1 synthetic oil. That has helped the noise quite a bit, but it is still there. It seems to less noticable as you pick up speed in the car. One mechanic from the old school has advised me to drain down a little of the oil and add a bottle of Marvel Mystery oil. He said he had used it many times where lifters were noisy and in every case it stopped the noise almost completely if not completely. I have done a search and read several posts on the oil, but have not seen any on the gas engines. Can anyone give me their experiences/opinions on this and will it help. I do know eventually I will have to do some work on the lifter/rockers/cams, but unfortunately I am not ready for the repair this soon. Thanks to all who reply.

jbhebert · #2 05-07-2004, 02:31 PM

I like to use MMO on the cam/lifters/etc of a car that has been sitting for a while that I'm preparing to start. I also had a '72 Bronco with pretty severe lifter noise that a pint or so of MMO completely silenced. Of course, your results may vary, and you don't want to use it to "quick fix" a potentially serious problem. Mobile 1 should give you similar results, so if it didn't fix your problem you might need to dig deeper into the cause.

#3 05-07-2004, 06:36 PM

I have a diesel however when it was clattering a Mercedes tech
said to use the Marvel Mystery oil and get it good and hot and run at high RPM's, which would clean up varnish & shellac deposits
The procedure worked Marvelously.

rsl007 · #4 05-07-2004, 08:03 PM

How much MMO did you use...1 Quart in place of regular oil?
RSL

#5 05-07-2004, 09:06 PM

used 1 & 1/2 qt's Cars capacity is 8 & 1/2 qt's

william rogers · #6 05-08-2004, 03:17 AM

MMO is a water displacing oil great for air tools. I sure don't want any in my MB engines.A good high detergent oil like diesel rated Delo 400 15/40 might help Iv'e been using it in my diesels and my 500 Se quieted down the SE a good bit.I may change to another Dino oil like Castrol now that the Dellos done it's clean up job............

William Rogers.......

#7 05-08-2004, 08:45 AM

I'm totally with William on this. There is a can in my shop close to where I keep my air tools. Air tools are the ONLY things I own that will ever taste it.

In the distant past I have used it to decarbon various engines. But that was in the days before motor oil formulas underwent such drastic improvements.

I'm curious, what has been the oil change frequency on this car?

Have a great day,

SCOTTFISH · #8 05-10-2004, 11:01 AM

I bought the car when it had exactly 100k on it. I immediately changed the oil in it to Mobil synthetic. My experience with Mobil synthetic is that you can typically go a bit longer on oil changes than with regular oil. I have made a practice of changing it between 5k-6k. I have checked with my local MB dealer and they recommend with synthetic oil changes at 7500 miles. The car does not seem to use a drop of oil in between changes.

#9 05-10-2004, 11:56 AM

I think that you now have the car on a good oil change schedule given the oil that you are using. I expect that the previous owner was not so dilligent.

Using the MM will really do nothing for you. A few oil changes of the Mobil One will do as much cleaning as can be done. If you still have the ticking, you might do a quick change or two with a super high detergent oil such as Delo 400. This is designed especially for diesels so it has very high detergent content to accomplish soot dispersal. It is also certified with the latest gas engine rating.

Since it is much less expensive than your normal brew, you can drain the engine while hot to get as much crud out as possible, put in a new filter and a fill of the Delo. Run it about 500 miles and change again while piping hot. This will get out the most gunk. Then go back to your synthetic brew with a clean filter.

This is the best and safest way to deal with a gunked engine. Using non lubricating solvents to clean an engine is risky.

Best of luck,

csnow · #10 05-10-2004, 01:33 PM

No great mystery.

MMO is mostly kerosene.

nglitz · #11 08-14-2004, 06:43 PM

Quote:

Originally Posted by csnow

No great mystery.

MMO is mostly kerosene.

Here's what's really in it:

http://images.shipstore.com/ss/images/mav/mavmmoMSDS.pdf

Mineral spirits, napthalenic petroleum distillates. No kerosene (paraffinic petroleum).

Rafi · #12 08-15-2004, 10:21 AM

nglitz - forgot to write in your text the most important active component - chlorinated hydrocarbons.

It is mostly mineral oil because that is what the composnents are dissoved in othrwise it will just be few drops of chlorinated hydrocarbons, who is going to pay few buck for few drops of material?

Also if you overdo it will start dissolving gaskets and seals as well.

dreamer · #13 08-29-2004, 09:22 PM

There's a former member who has some Auto RX i believe it's called. He had a ticking tapping issue and he said that the more he used the quieter it got. If you'd like i can ask him if he still wants to sell it you may get it cheaper from him than at a store. JimF talks about it on his website from what i've heard it's pretty good i plan on getting some myself.

Jim

afmcorp · #14 08-30-2004, 01:38 AM

back in the 60's when i was racing 1/4 mile at irwindale (the original) Lion's and several other locations, i was racing a 1966 Plymouth Belvedere(426 Hemi) and a 1968 RoadRunner(383B). when i had the hemi i was able to get in a few places just cause i had the hemi. i would go into Gene Ollies and sit around and listen to these guys and i picked up a number of things from them. anyway guess what the hotrods used to assemble an engine. yep MMO soaking the piston and rings and lifters with it. of course cams, cranks and pumps got white assembly grease and with those expensive new engines you cranked with the starter till pressure showed up on the gauge before throwing fire to the plugs.

MMO is a good detergent and can be added to fuel and oil. but they are not meant to substitute for oil. they do not have the viscosity to withstand the pressures of the hot engines.

actually for my money if i got a bad lifter or valve comp don't try to save it. pitch it and replace with a new one. and if you see a bad cam lobe or rocker they are not going to heal themselves so i'd vote for replacement asap.

but i know i'm on the outside when it comes to oil choice here on the forum. all my cars get dino 20w50w high mileage castrol. year round and oil change at 2500 miles. but i use regular unleaded gas as well so now that i've confessed and committed sacrilege to the MBZ brand please don't boot me off the forum. i do however use premium when it gets really cold say about zero.

Mike Murrell · #15 08-30-2004, 01:50 AM

Quote:

Originally Posted by afmcorp

but i know i'm on the outside when it comes to oil choice here on the forum. all my cars get dino 20w50w high mileage castrol. year round and oil change at 2500 miles. but i use regular unleaded gas as well so now that i've confessed and committed sacrilege to the MBZ brand please don't boot me off the forum. i do however use premium when it gets really cold say about zero.

Craig - Lots of us older folks have used Castrol 20W-50 for years and that's why we have cars that are as old as they are. As one knowledgeable member here reported sometime back(JackD), synthetic pays a higher margin to the oil companies. The so-called "extended" changed interval has turned out to be a lot of hooey. I've taken too many cars past 300K using dino.

It's been reported more than once here that the 103 motors run better on mid-grade which is just overpriced lower grade.