So I was rebuilding my brake calipers for my motorcycle and I had saw some Marvel's Mystery Oil on the shelf and grabbed a bottle. While I was cleaning everything I tossed the caliper piston O-rings and seal in some Marvel's and let it sit for a couple of day before I started to re-assemble.

The o-ring and seal on the right is what came out after soaking and the ones on the left are the new OEM parts I had to order because there was no way in hell they were going back in..can't believe they expanded so much...anyone every use Marvel's?

IMG_1128 (800x600)

Marvels (800x450)

I never used it like that but had a grandfather that swore by it therefore it was always present in my Dad's workshop.

Probably the two best uses I ever found for the stuff was when i was rebuilding an old Honda SL350 motorcycle my Sunday School teacher gave me in 6th grade:

1) Tank was a mess inside from sitting so we poured MMO in and tossed in some gravel. Shook the shit out of it every so often and when we drained it it was night and day. We then soaked an old sheet in MMO and stuffed it into tank to keep it from rusting while I rebuilt bike on paper route money.

2) Same bike, old beat up chain. Soaked in MMO for a few days that hung chain to allow all oil to drain and stored in oil soaked towel. I do not think it was an O ring chain.

quote:

Originally posted by Kevmo:
I never used it like that but had a grandfather that swore by it therefore it was always present in my Dad's workshop.

Probably the two best uses I ever found for the stuff was when i was rebuilding an old Honda SL350 motorcycle my Sunday School teacher gave me in 6th grade:

1) Tank was a mess inside from sitting so we poured MMO in and tossed in some gravel. Shook the shit out of it every so often and when we drained it it was night and day. We then soaked an old sheet in MMO and stuffed it into tank to keep it from rusting while I rebuilt bike on paper route money.

2) Same bike, old beat up chain. Soaked in MMO for a few days that hung chain to allow all oil to drain and stored in oil soaked towel. I do not think it was an O ring chain.

well chit...that reminds me...I soaked my o ring chain in it too.

quote:

Originally posted by tatortodd:
NTSB Blames it for a plane crash

Seriously! Someone just decided to add oil to aircraft engine fuel‽

quote:

Originally posted by sigfreund:

quote:

Originally posted by tatortodd:
NTSB Blames it for a plane crash

Seriously! Someone just decided to add oil to aircraft engine fuel‽

Yep and tgey were bad at math too as dumping a quart into an 18 gal tank isn’t 1 part per hundred.

a quote from the NTSB report.

quote:

The contents of Marvel Mystery Oil were 74 percent mineral oil, 25 percent stoddard solvent, and 1 percent lard.

I use it to lube my firearms after cleaning.
Works for me.

I can remember seeing this used on vehicles that weren't running well due to valve seat issues/sticking valves from sitting,etc.
This would be uh... some years ago. People used to leave Jeeps/Land Rovers in hunting camps and they would sit for months and sometimes years without being turned over. Valves would stick and this was the the cure-

Here was the technique used on conventionally aspirated engines- you would open the hood and remove the air filter, take the container holding Marvel Mystery Oil and begin slowing pouring a thin stream into the carb throat with the engine running at idle. The engine would immediately begin generating a lot of smoke (this was used on pre-cat exhaust systems).
The engine would also begin to sputter and begin to drop in rpm. You would pour just the right amount in order to keep the engine just on the edge of cutting out. Once you had poured around a pint you would cut the engine off and let it be for thirty minutes.

It would start up with a bit of smoke, but I have seen it benefit engine performance after this routine. From a rough idle to a smooth idle. (I was also told you could do virtually the same routine with automatic transmission fluid). But I always saw this performed with Marvel Mystery Oil.

This is similar to the "fogging oil" technique for storing engines.

I don’t know why you would put a brake seal into that.
EP rubber isn’t compatible with that type of product just like Buna rubber will swell up and eventually break down in brake fluid.

quote:

Originally posted by DSgrouse:
The contents of Marvel Mystery Oil were 74 percent mineral oil, 25 percent stoddard solvent, and 1 percent lard.

Cool. So you can make your own for pennies.

quote:

Originally posted by dlcchp:
I use it to lube my firearms after cleaning.
Works for me.

Rem Oil and Hoppes Lubricating Oil are mostly mineral oil too.

I put some in my 99 Chevy Tahoe years ago (following instructions). Tahoe broke down the next day I ended up putting new fuel pump in it.

Never used it again.

But has anyone personal experience with adding it to engine oil? A few in the clubs around here swear by it for old pushrod engines, I haven’t tried it myself.

No petroleum on brake parts

I have added it to my lawn tractor, snow blower 13 year old car.

quote:

Originally posted by SigJacket:
But has anyone personal experience with adding it to engine oil? A few in the clubs around here swear by it for old pushrod engines, I haven’t tried it myself.

I’ve had great luck using a mix of 50% Marvel Mystery Oil and 50% Hoppe’s #9 to clean carbon deposits out of the bore the piston rides in on a P7M8 that was having trouble loading up and becoming difficult to cycle. It never would have occurred to me, but a smith who happens to be a member here suggested it and it worked like a champ.

I’ve never added it to oil, but use it to fog the boat engines for winter layup.

14 years, so far, so good!

MMO has its uses, but not in brake systems. Never, ever put petroleum-based anything on a brake hydraulic system seal, or exactly that will happen. Only use DOT3 or 4 brake fluid. (No DOT5 either except for a few specialty uses.) There are also special caliper assembly lubes. Similarly, when you finish using a container of brake fluid, destroy and shit-can it to eliminate the possibility of some other fluid being put in it and subsequently finding its way into your brakes. You're lucky to only be inconvenienced and have to buy new caliper kits. I have seen a number of car brake systems come to some serious grief when, for example, the master cylinder gets mistaken for the power steering.

I had a Mazda B2200 that I would us a oil flush every three oil changes. I skipped doing it and the valve started tapping until the motor warmed up. Added 8 ounces and it freed them up in about a day.

Many years ago I used it sometimes in engines that were poorly maintained. I haven’t used it since I discovered Seafoam.

Seafoam is now my do-everything-miracle-in-a-can.