2w (edited)

My Auburn 8-98 Needs Some Love

I have been fighting on an off with a sticking valve for about a year and a half and today it stuck and never really loosened up. Usually once the car came up to temperature it was fine. I am guessing either I have a bent valve or just a lot of crud. I need to send the car somewhere to get the engine work done. I am leaning toward ACD in Broken Arrow but open to suggestions if anyone has one. When the valve is not stuck the car runs great so I am guessing that my bottom end must be pretty good. Hopefully we can just do the valve train.

1 / 4

Oct 18, 2026

Post your reply…

Replies (9)

· 2w

Tim Purrier at Straight-Eight is amazing! I’d just send it there!

· 2w

Have you tried an upper lube like Marvel Mystery Oil? Most effective if you use it in the oil but you can use it in the gas also.

How many miles have you put on the car recently? Marvel mystery oil and some real miles could really loosen a sticky valve.

· 2w

+1 on the upper lube. Won't help if there is a bent valve stem but if the car was running ethanol gas at any point you could have sticking valves.

· 2w

We need @ShawnG or @Edinmass to chime in. I’ve had good luck with upper lube but that won’t help if a valve stem is bent.

As for shops, your location matters a little. I second the straight eight recommendation.

· 2w

I have run about every sort of potion you could and Ed has been advising me. It is a weird stick that is schizophrenic. It will be fine two drives and then be screwed up for the third. Car never sits for more than a couple of weeks. Lives in air conditioning.

· 2w

Don’t get Ed started with lube 😂

· 2w

I wonder if there's some varnish from stale gas on the stem or guide.
Sometimes disassembly and cleaning is the only thing that will help it.
The repair could be done in-car. Just pull the head and manifolds, pull the tappet cover and pull the valve out. Even if it needed a guide or new valve, it's not that bad.

(edited)

· 1w

Whenever I’ve encountered sticky valves in flathead engines, I’ve had good success pouring Marvel Mystery Oil directly down the carburetor while the engine is running.

I also like to add a generous amount of Marvel Mystery Oil to the gasoline and put some miles on the car. Don’t be alarmed if the engine smokes a little while running on the heavily treated fuel.

In my experience, this approach has been very successful in freeing up sticky valves.