Performed a compression check and received the following results:

Compression test: cyl 6 ÔÇô 140 5 ÔÇô 140 4 ÔÇô 140 3 - 120 2 - 140 1 - 120

about 100k miles....So 1 & 3 are 20 down (I guess they are entitled) ...any significance to that or is that within acceptable wear and performance expectations?

Thanks for any thoughts

Submitted by bfahnest@gmail.com on Thu, 05/15/2014 - 03:27

sounds like a plan. Also, I realized in the middle of the night that I had said Valve Guides when I meant valve seats. Best of luck and sounds like you are on the right track

Bruce

Submitted by bonnettoboot@e… on Wed, 05/14/2014 - 18:53

The two weak ones are going to make it run a little worse but thats all. The only serious thing that should be checked is the valve clearance.

Submitted by salzgreen@gmail.com on Wed, 05/14/2014 - 18:52

Hi Bruce...

we chatted before-a few weeks ago...I am doing the whole Marvel Mystery gig I mentioned then....pulled the plugs and ran about 50 ounces down the cylinders...started with a lot in each, then every two days....a bit more and turning over - plugs out...50 ounces total

this went on for two weeks...had a little mmo come out the south intake, but that was it...yesterday, pulled the air cleaner and looked to make sure I wasn't flooded with mmo, then, ran it out plugs out to clear the cylinders...then, old plugs in and fired it up...looked like heaven here for awhile...white smoke!

Then, a buddy has a vacuum check...and we ran that test...perfect results...concludes the valves are OK

The reason I am doing all of this ridiculous stuff is that the car burns 1 quart per 100 miles...I am running 20/50...

so, about a quart of that stuff is now down in the crankcase with the 20/50...so I said, what the hell, ran it about 30 miles up the coast last evening...ran great...plan to run it a little more to see if anything improves...not pushing, just a steady 60

the compression test was done about a year ago before I went thru all of this...I plan to do another compression test after I refresh the oil to see if the magic red oil did anything--maybe loosen a stuck ring....or if I am just dreamin'

thinking I might also mix it with some gas and fog the trumpets before I refresh the oil..

thanks for your input

Submitted by bfahnest@gmail.com on Wed, 05/14/2014 - 18:24

Me being old school, I would say that more then 10% difference and you need to do some work. No the question is is it valve guides or rings. We used to squirt a little oil in they cylinders (easy with an old trigger type oil can with a flexible hose and tip) squirt a little oil to the side of the cyl. through the spark plug hole. run you compression test again and if you compression in each cyl becomes more uniform and normal . It is rings. if they do not improve it is valve guides. In either case now that you have that knowledge with 100 miles on the clock and the fact that it probable went a few years without changing oil at some point it would be a good time to do both. If you are not using 50 weight oil or if you have changed to synthetic. Try the good old stuff. 50 weight. If you are not planning on keeping the car and it is not smoking camels hit it with some marvels mystery oil and tell the buyer that the compression is not bad, but it is off by 20 lbs in two cyls. Hope that hels

Bruce