Success with Marvel Mystery Oil

[fishinbama]

I have a cousin who works offshore as a mechanic. Every year he rebuilds giant 2 stroke diesels. He says that they purchase MMO by the barrel to have shipped out there. I decided to try some for carburated lawnmower that "hunts" (rpm up and down). My engineer father in law just said some small engines do that. Well, mmo cured it. I have purchased more and am putting it only in my fuel.

[brucepick]

I think the physical problem in my HX is in the EGR passages, and that Marvel Mystery Oil cleans up just enough crud to allow some flow there. From photos the EGR passages look to be about 1/8 inch diameter channels machined into a casting below the fuel injector rail. (See this post: How to Clean EGR Ports / Passages - Honda Civic Forum. And you can google for more writeups, youtubes etc.)

Somewhere I read the HX opens the EGR valve during lean burn; clogged passages would prevent the "wanted" flow of exhaust gas back to the intake system. I've occasionally had CEL stating insufficient EGR flow, CELs not helped by cleaning and later replacing the EGR valve.

I know, really I should clean the EGR passages but I'm not too much of a mechanic and don't relish the thought of taking apart all that stuff including the well-sealed fuel system components. One of these days in warmer weather I might get up the nerve and time to do it.

[Marc F.]

Bruce,

Seafoam produces serious fumes when burned. BUT it almost melts carbon build up. You might try dripping straight Seafoam into the egr channel if you can get to it. Let it sit for a while. I may open them up without taking the engine apart. I have used in several engines with good results.

[Thymeclock]

Originally Posted by Marc F.

Bruce,

Seafoam produces serious fumes when burned. BUT it almost melts carbon build up. You might try dripping straight Seafoam into the egr channel if you can get to it. Let it sit for a while. I may open them up without taking the engine apart. I have used in several engines with good results.

I'm not doubting your belief in it or your claimed success with it. But I am skeptical enough to question what its components are. For anyone else who is interested, this discussion might be of interest: click here.

[Marc F.]

Thyme, no worries man, I have never researched what was in it, I just used it. I dont use it everytime I fill up.

My current car (82 Oldsmobile w/307) had sat for 10 years unused. I used the Seafoam Trans treatment in a flush and filter change and Seafoam in 2 oil changes. But I dont put it in and leave it. I added it and drove for a few hours, it makes the oil really dark really fast. I had a slight lifter tick, its gone. I have no proof but I am thinking it helped loosened up the varnish that was plugging the lifter so it can function correctly. I also dont know what solvents like these will do to the seals long term. I do know when you pour it in the carb it cleans the carbon build up visibley.

I have seen where people use a vacuum line to introduce it to engine and the shut it off to sit and then the impressive clouds of smoke. I have never done that. I did use a concentrated amount in a '46 Farmall Tractor, the fumes about killed me! But it ran better after the gas/Seafoam treatment.

I dont know if it will help the egr passage or not, its the only thing I can offer that I have experience with. Its like all snake oil treatments, use with skeptism.

[Thymeclock]

Originally Posted by Marc F.

Thyme, no worries man, I have never researched what was in it, I just used it. I dont use it everytime I fill up.

I'm not worried, just curious. I found some interesting information on SeaFoam and am opening it as a new thread. (click here)

[brucepick]

I seafoamed this car 2-3 times already, didn't help the lean burn problem. You can see the ick being blown out the tailpipe though!

Currently running 2.5 oz Marvel Mystery Oil (MMO) per 10 gallons gas. I'm using one of these to easily measure fractions of an ounce of MMO at the pump. Search on "Adjustable Measuring Cup" on Amazon or google etc.