Stuck rings

[hemmah]

My 1969 911T with 1970 911T engine was in storage for 4 years. When my mechanic started it a few months ago most cylinders had low compression. My mechanic added 1 oz or so of oil to all cylinders to loosen the rings. The oiled cylinders soaked for 2 weeks and 1, 2, 4 and 5 returned to 150 PSI or so. 3 and 6 were around 100 PSI.

I then shipped my 911T to my new home to work on the issues created during storage and my history of ignorance. Recently, I've post more than 20 questions and WTB on Pelican Tech Forums and read a lot. I rebuilt the Webers and adjusted best I can. So I'm a bit smarted and have the 911T running Ok but still cylinders 3 and 6 are lower compression and fowling spark plugs.

This week I poured 1 oz Marvel Mystery Oil (MMO) in cylinder 3 and 6 and change the oil to a denser grade 20W 50 and added MMO to the non-Ethanol gas. Twenty hours later I put the cleaned plugs back in and fired her up. Smoke abound but it idled better after the air cleared. I ran around town and it does run better but after awhile a few back fires. I knew I was still fowling plugs. Sure enough plugs 3 and 6 are fowling. Maybe less but still lots of soot.

I figured cylinders 3 and 6 valves must have been open during the 4 years set and condensation rusted rings and other bad things. A guess without all the facts.

Any suggestions? I do have Engine Release penetrating oil that I could try. Or do I just keep MMO in the gas and more soakings. Maybe soak for 2 weeks on 3 and 6.

Looking to do the best.


Thanks
Steve

[Two Rivers]

Sounds like a mechanical problem and all the magical oils will not fix it.

[porsche930dude]

did you put any mmo in the oil? youll probrobly need a few quarts since there is so much oil but mmo did work to free the rings on my truck with a 350 chevy.

[hemmah]

Thanks for the suggestions

[Joe Bob]

Beyond adding MMO to the oil and running the pissoutta it....it's a tear down.