Compression tests were good, leak down was good but the car still smokes during deceleration. Just normal driving. The engine runs very well and I am not ready to rebuild a motor. So....does anyone have any experience using Marvel Mystery Oil or another additive to slow down the smoking?

Thanks!

Marvel Mystery oil and most leak-stop additives are just mineral spirits that will make the seals swell.

Your issue is most likely due to worn valve guides which are bronze and will be unaffected by the product.

If you can run a thicker weight of oil, that might help a little.

20W-50 & go Ampex. I used to work for them in the early "80s. I have an AG-440 & an ATR-800. Both are 1/2" 4 track machines in excellent condition. They have so much dynamic range that Dolby NR isn't necessary.

Thank you for the input.

Roger

Thank you...that's what Im running.

Thanks, I am running 20-50 Brad Penn now.

marvel is not going to stop the problem.
just live with it, it you don't want to do a top end.

Thanks, I'm running Brad Penn 20-50 now. Will the car be prone to major breakdown if I DONT' do a valve job right away?

Do you think I'd be in danger of a breakdown NOW if I don't do a valve job right away?

IMHO, no.

Go Ampex!!!

I have 2- 351 2 track machines and a AG440. Love them all. We make a new recording tape called Capture. It sounds fantastic on my old ampexes.

www.splicit.com

Roger

Keep them heads clean & demagnetized. Right on Roger!!!

a little smoke isn't going to leave you on the side of the road..
you should be fine to drive it.

This is for Ampex351. This is the control room for my recording studio.

And I thought the 914 might be a safe way of avoiding the music industry….lol

Pretty sure I’ve still got a Tascam 8-track and rack of Ashly compressors in storage if anyone wants to trade for actual car parts!

It's just for fun.