The best engine gum and varnish remover is........

[BCSpokerider]

Just wondering what you all use, and recommend for and internal gum and varnish remover. So many brands on the shelves to choose from.......

148K on the festy.......has prolly never seen any.

Thanks.

[getnpsi]

I have used seafoam, marvel mystery oil, diesel fuel (cranking w/ no start sit overnight crank again then drain) and water mist into the intake with the engine running. All in an attempt to undo issues caused by previous owners. I don't use oil additives in the cars I've owned and maintained myself. Fuel adds yes when the cars have sat a while.

Varnish is just a staining of components and really has little to do with how it runs. Varnish is something that is addressed with carbs. I had success in a tired 1.3 aspire just using motorcraft 5w-20 (yes car is speced for 30w) and seemed to get an increase in pep because the oil is thinner. You are in Canada and I see no problem going to this oil. I would pull the valve cover and see if there is actual black/brown goo clinging to pieces under there. If there is not then just keep changing the oil like you should and get a new PCV. Also try to not take a lot of short trips. Get a real mazda thermostat to ensure your engine is getting to correct operating temperature.

Don't get engine cleaners like gunk and other flush solvents. If ther is goo in your engine it can be freed up and get into your oil pump pickup causing damage. Marvel mystery oil is a product that people use in their fuel systems and in the oil. Its more oil than anything so again if you plan on keeping your car for a long long time just get better quality oils and change often. Save your money.

[JPT]

I've used Marvel Mystery Oil for years. It works good.

Something to watch out for when using "Motor-Flush-In-A-Can" on old engines (besides loose sludge running around in your engine) is that there could be sludge around worn seals. The sludge sometimes is what's preventing oil leaks. I've seen engines leak like crazy after a treatment or two of that stuff.

[boydg1]

.... How much of Marvel Mystery oil to a tank of Festie gas do you add? :???:

I've used Marvel Mystery Oil for years. It works good.

Something to watch out for when using "Motor-Flush-In-A-Can" on old engines (besides loose sludge running around in your engine) is that there could be sludge around worn seals. The sludge sometimes is what's preventing oil leaks. I've seen engines leak like crazy after a treatment or two of that stuff.

[JPT]

^ I've never used it in a gas tank. I put it in the crankcase a day before an oil change (same method as getinpsi uses). Pour it in, let the engine run for a bit, shut it off, let it sit for a while (or overnight) restart and let it run 'til the engine is warm and then change the oil. It removes and dissolves sludge gradually, unlike those motor flushes (which are basically solvent) which can loosen chunks. If you have lots of sludge, don't count on cleaning all of it out with just one treatment. This is one of those gradual processes.

You can even drive your car with it in the crankcase. Something you should NEVER do with motor flush.

It's good at loosening sticky lifters too.

[villageidiot]

in vehicles past and to some customers cars with filthy sludgy oils (im a mechanic) i replace one quart of oil with a quart of dex/merc trans fluid. brakes up a fair amount of sludge and hasnt harmed anything to date

[navdoc101]

I've used Marvel in the past in other vehicals, good stuf & seafoam in my 'tiva resently. use a good quality high milage oil & filter. I use a K&N filter & Castrol on my '01 Tacoma. Haven't change the oil in the 'Tiva yet.

[sc72]

trans fluid

Hey villageidiot, how long are you leaving the trans fluid in the crank case, a full 3000 mile oil change or less.

[BCSpokerider]

I have used seafoam, marvel mystery oil, diesel fuel (cranking w/ no start sit overnight crank again then drain) and water mist into the intake with the engine running. All in an attempt to undo issues caused by previous owners. I don't use oil additives in the cars I've owned and maintained myself. Fuel adds yes when the cars have sat a while.

Varnish is just a staining of components and really has little to do with how it runs. Varnish is something that is addressed with carbs. I had success in a tired 1.3 aspire just using motorcraft 5w-20 (yes car is speced for 30w) and seemed to get an increase in pep because the oil is thinner. You are in Canada and I see no problem going to this oil. I would pull the valve cover and see if there is actual black/brown goo clinging to pieces under there. If there is not then just keep changing the oil like you should and get a new PCV. Also try to not take a lot of short trips. Get a real mazda thermostat to ensure your engine is getting to correct operating temperature.

Don't get engine cleaners like gunk and other flush solvents. If ther is goo in your engine it can be freed up and get into your oil pump pickup causing damage. Marvel mystery oil is a product that people use in their fuel systems and in the oil. Its more oil than anything so again if you plan on keeping your car for a long long time just get better quality oils and change often. Save your money.

Thanks for your thoughts.
I did have the valve cover off in order to replace the gasket, and now I have the oil pan off, to yup.......replace the gasket..... So having had a good look at both ends, I can say there is no heavy sludge in the engine, or in the bottom of the oil pan, but a thin coating of tenatious goo that was easlily removed with detergent and a brush. The internals have the *brown* look to them.

When I had the air box to EFI tubing off, I had noticed some oil had been blown into the tube. The PCV ball was stuck in the valve, so I cleaned it out to free it up again. Perhaps that is, or was the cause of the increased crankcase pressure pushing oil up?

Also thinking it may be blow-by, and thus my question of the best product to use to free sticking piston rings.

Don`t think we have Marvel Mystery Oil here.

[getnpsi]

Yes a flaky pcv is the main cause of blowby where it shouldn't be. if its really messed it up it increases blowby. I'd just replace it, ours is under 7 bucks at full blown retail.