Stickey valves

[ebarras]

What causes valves to get hung up in a 8ba flathead engine: Inactivity, dirty, gunked up???

[r_reed]

all of the above? most people say 4 oz. of Marvel Mystery Oil per 10 gallons of gas to keep the valves from sticking.

[Tinker]

If you dont drive a lot, run the engine to temp and then drizzle some mmo down the carb when its running. Cant hurt anything and might lub the upper end.

[GOSFAST]

Hanging valves are mostly caused by moisture finding it's way into the guide and stem area and eventually causing damage to both.

The moisture is mostly caused by short-trips, and this same moisture will play hard on non-stainless exhaust systems as well.

It's for this reason when we do any Flathead rebuilds, whether stock or hi-perf deals, we always install bronze liners in the guides. Since we've been lining the guides we haven't had a single valve "hang". Not a one!!

It also helps to use some decent "Stainless" valves, this helps big time.

I know it's more difficult for a "fix" when it's a running unit, but it will be a constant battle in the end without the liners.

Thanks, Gary in N.Y.

P.S. Most customers really don't care for the add'l initial cost to do the liners on an overhaul, but you can see the aggravation it saves in the end. No need to go back inside the build, saves much labor and expense (gaskets, etc) to do it right the first time. Every Flathead we do gets the guides done, the "Stainless" valves, and Viton stem seals. This is a non-negotiable item here on new builds. Here's a shot of a finished guide with the Viton seal.

[G.M.]

Most sticky valves are caused by a thin white residue left on the valves from this new gas. Even driving the car if you don't add MMO to the gas after about 2 tanks full without it the valves will start sticking. Most people probly have sticky valves and don't even know it. After the engine warms up slow down to 10 MPH in high gear and step on the gas pedal. If the engine bucks slightly the valves are most likely sticking a little. Do the treatment described above, drive about 5 mile and do the slow down in
high gear test again and it should pick up slowly without bucking. A slight miss once in a while at driving speed can also indicate sticky valves. G.M.

[Peterooster]

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I went with a synthetic oil to end valve sticking in my 1950 8BA. Pete

[66miles]

I suspect I got sticking valves in my old motor ( possibly also gummed up compression rings). This old timer has probably never been pulled apart since the day it was built but runs OK though a little rough. Did a compression test and was fairly even but around 20PSI lower than normal. Alan on the barn suggested pouring a little MMO down the plug holes then redoing the test. Can't seem to get MMO here so used diesel instead. Sure enough the pressures lifted 5-10 pounds. Now I'm gonna fill those pots to the top with diesel and hand-crank her over. That's gotta soak those valve guides and stems. Who knows. Might just do the trick. Then I gotta find some MMO for future.

[B-O-B]

Can't find MMO use ATF & run it thru the engine(via carb) & put some in the fuel also.
If you are going to fill the holes & turn it over leave the plugs out & cover the fenders.

[66miles]

ATF. I heard that one too from a guy today in the workshop where I tried to find some MMO. Would ATF do the same thing? Wouldn't do any damage?

[va t]

Trickle some Shaler Risilone down the carb at idle. If engine doesn't smooth out immediately, let it soak overnight. I've never used Risilone as an oil additive but have smoothed out sticky valves several times.

In an experiment I put some risilone on a badly carboned combustion chamber. The next morning the carbon was soft to the touch of my finger.

[66miles]

So many products no-one seems to have heard of in NZ. Only things I see on the shelves is STP and Wynns.

[Mike B]

ATF doesn't have lubricant's...does it?

I know it's high in detergents, but is it a good thing to put into the carb?

[Graeme / New Zealand]

Originally Posted by 66miles

So many products no-one seems to have heard of in NZ. Only things I see on the shelves is STP and Wynns.

Try Moreys upper cylinder lubricant and injector cleaner...get it a Supercheap or Repco.

GB

[cmbrucew]

Mike B

I don't think ATF has any detergents. The engineers don't want the oil to carry the debris from the disc's all thru the valves.

Bruce

Works good
Lasts long time

[Mike B]

That makes sense Bruce.

[B-O-B]

Can not tell you what is in A T F & what is not in it. I only know from experience that that it worked on my F-500 223. It was hardly running so I worked about a 1/2 quart thru the carb & it perked it up, then I put close to another qt in the gas & ran it i/2 throttle for a bit. Mosquito abatement people would have hired me if they had seen the smoke coming out of that ol ford. Ran good after that till I sold it. Been a while but I may added some acetone also C R S strikes again on the acetone.

[rotorwrench]

Early type A ATF is pretty much straight mineral oil but may have had some whale oil in there too in the later 50s. Dexron type B for GM trannies isn't far behind that. The Type F fluid does have some solvents in it. They were more a conditioner but there are mild detergent factors to keep things clean. That was why they always used to warn folks not to put Type F in a Chevy although it will work if you start from square one or after an overhaul.

Dexron II was starting to get away from whale oil and trying jojoba and other oils. In the late Dexron and Mercon oils, they are getting into the synthetic blend range more and more plus all the friction modifiers or conditioners.

The stuff definitely ain't motor oil. We use ATF in the pitch bearings on the Robinson helicopters.

[B-O-B]

Thanks rotorwrench I forgot to mention the the ATF was type F. I do not need it anymore as I sold the T bird so I had a few extra gallons of the stuff.

[G.M.]

The only thing similar about ATF and MMO is the color. I have a friend who is also a long time MMO user. He is a principal in a chemical company and had the chemist look into the materials used in MMO. There was one product in it that they said was to expensive to reproduce it. What the product is I don't know but MMO must buy it by the tank truck or rail car tanker. I have used it for 65 years and solved more problems with it than I have time to post. In most cases it works in minutes or in a few miles. It works in gas and diesel engines ,cleans fuel injectors and sticky shift problems in automatic transmissions. G.M.

[rotorwrench]

A person can tell by the smell that is has both a lubricating oil property and a solvent but what they are and in what concentrations is truely the mystery about MMO.