Sticky valves: what is the procedure?

LizardsA

LizardsA

Senior Member
I have a 1930 Sport Coupe that appears to have valves stuck open. This was a diagnosis when I discovered that there is little compression when I start her. Certainly not enough power to move off under her own power. What is the procedure to check the valves - do I need to lift the head off or not?
 
Do you have SEA-FOAM in Africa? Put one can in the oil and one can in the gas.

No need to pull the head yet. If you remove the side cover you can get some penatrating oil on the stems, but you can also spray some through the spark plug holes towards the valves and hopefully get some on the stems. You may have to use a bent screwdriver to push the valves down to work them back and forth.

Do you have to use ethanol in your gas in Africa? That garbage is famous for making valves stick.
 
Hi Tom,
Not familiar at all with SEA-FOAM here in South Africa.
And no, we run straight unleaded gas.
Thanks for the help anyway.
Mike
 
If engine not used for a while, gasoline evaporates & valve guides & stems get "gummy" with fuel residue.

Vintage remedy learned years ago & used often on vintage cars & tractors to free sticky & stuck valves prior to Kroil, PB Blaster, Liquid Wrench, etc., as follows:

1. Remove 4 spark plugs & very slowly pour one (1) cup of "Kerosene" (not gasoline), in each of the (4) cylinders.

2. Replace plugs & allow engine to sit for 24 hours.

3. Start engine -- lots of smoke -- after a few minutes, after valves free, change oil.

4. Worked for me several times.
 
If a valve is stuck open, you will have a dead miss on the cylinder in question. I had a sticky slow valve action once that was caused by ethanol adultrated gas. I replaced the bad gas and added Marvel mystery oil to the crankcase and the fuel. I also disconnected the vacume line and stuck the upper end into a bottle of marvel mystery oil and let the vacume of the running engine draw the mystery oil up the intake to the valves.The mystery oil caused quite a bit of smoke but after a short time it smoothed up and the power returned. This should help if the valves are really the problem. Good luck.
 
Purdy Swoft said:
I also disconnected the vacume line and stuck the upper end into a bottle of marvel mystery oil and let the vacume of the running engine draw the mystery oil up the intake to the valves.The mystery oil caused quite a bit of smoke but after a short time it smoothed up and the power returned. This should help if the valves are really the problem. Good luck.
Click to expand...

Make sure you do this outside.. don't ask me how I know :D
 
As an alternative to Marvel Mystery Oil (if it is not available in S.A.), one might use automatic transmission fluid. Or even a concoction of ATF and Kerosene.
 
Thanks to you all for the advice. I shall try the suggestions out and let you know soon. Regards Mike
 
Hey Mike,
If you do not have marvel mystery oil either..in Africa, you probably have automatic transmission fluid. Remove plugs and pour several ounces down each spark plug hole. Replace the plugs and hand crank the engine over several times and let set overnight, Try firing engine off next day and repeat process till all valves are free/loose.
Note: If you see that your making progress this method, let the engine warm up completely , and repeat process...take out plugs , pouring in ATF and letting it sit overnight.
Many decades ago, as youngsters, we learned about using auto trans fluid from watching old timers then. I think that what was called ATF then is now pretty much like Marvel Mystery Oil;). Either way..it works,eh
 
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I was going to say ATF also. You could remove the manifolds and spray the guides that way and not remove the head......
 
I have on 2 occasions used half and half of kerosine and ATF. I then followed the procedure as above ( Mr. Chauvin ). yes it does make a lot of smoke. My father told me this had never failed for him and he was a great farm boy mechanic ! Please report back !
AL
 
The unleaded gasoline of which you speak has the tetra-ethyl-lead replaced with a chemical referred to as MMT. This stuff becomes very sticky as it ages in the gas tank of a long-sitting vehicle and when an engine (after a long hiatus) is started on this type of stale gas, the MMT coats the intake valve stems. When the warmed-up engine is shut off and allowed to cool down, the intake stems become "glued" to the guides. Two intakes will be partially open, the other two closed. When you go to start the engine next time, the two partially open intakes will open completely while the remaining two will reluctantly open all the way. They just won't close because of the MMT glue sticking the stems to the guides. A lot depends on how stale the gasoline has been allowed to become.
I've experienced this on OHV engines to the point of bending pushrods on seized intakes on engines that were running the day before on really stale gas. If you try to run some fresh gas mixed with the stale gas, you end up with the same situation, maybe less severe, with sluggish intake valve closure.
In the latter case, I was able to spray WD40 onto the valve stems to dissolve the sticky stuff. Removed the gas tank, drained out all the gas, flushed it, dried it out, reinstalled the tank and replenished it with fresh gasoline. End of problem.
The ethynol is not the real culprit here - it's the MMT lead replacement chemical.
 
While soaking it, leave some old plugs installed and ocassionally give it a looong crank with the key OFF. This is an Okie Compression Test. If it sounds like RRRRRRRRRRRRRRRRRR, in a smooth rythym, all valves are un-stuck! If it goes, RRRRR uka RRRRRRRRRRRR uka RRRRRRRR UKA, SOME ARE STILL STUCK! Oil it again & check again tomorrow, AFTER COFFEE! Bill W.
 
Mine turned over faster with the starter...That is what got me to thinking that the valves were sticky, moveing slowly and loseing compression.
 
van Dyck, Does Canadian gas still contain MMT? Here, within a few years of the MTBE ban, MMT went out of favor too. Everybody was afraid of the Manganese. Not that our Yankee gas doesn't contain any glue, it's just a different flavor. Like a second grade taste test. Do you prefer mucilage or paste?
 
In grammar school, we preferred the paste, 9 to 1 over mucilage for it's better taste & nutritional value. I'll ask Vermin for his preference. Bill W.
 
Purdy Swoft said:
Isn't musilage made from dead horses ?
Click to expand...
From the hooves & some not publicized back parts. Krazy Henry said there's cow parts used also & he knows his cow stuff!:eek:---------------Remember once when y'all licked an envelope & it was YUUUUUUUUUCK!!!:eek::eek::eek::eek::eek:
"THIS IS A PUBLIC SERVICE ANNOUNCEMENT" by Buster T. (Dog:cool:)
 

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