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Discussion Starter #1
Hi Friends

My 30 year storage mustang which is now driving has produced a valve noise problem. Three years ago the noise was slight. now after three more years of storage and about 50 miles on the road the noise is louder.

I did a leak down test with compressor to find you could play mozart on the leaky air from the dip stick tube. An ear to the carburetor finds hissing on many exhaust cylinders.

the psis were about 80 at one cylinder to 100 -130 at others and one at 150 ! So a valve lash tuning at hot running is in order.

My BIG question ............would buying a stuck valve oil treatment cleaner help. Prior to a valve adjustment or is it a waste of money?
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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And air leaking through the dipstick tube is generally an indicator of leaking piston rings, not valves.
Also air leaking at the carburetor indicates intake valves that aren't seating properly. Assuming you did your testing one cylinder at a time and made absolutely sure both valves on each cylinder were completely closed when that one was being tested.
 

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Discussion Starter #4
And air leaking through the dipstick tube is generally an indicator of leaking piston rings, not valves.
Also air leaking at the carburetor indicates intake valves that aren't seating properly. Assuming you did your testing one cylinder at a time and made absolutely sure both valves on each cylinder were completely closed when that one was being tested.
HI GypsyR

Thats exactly what I preformed. I just wondered if any build ups might impede valve travel.
 

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Remotely sort of possible but very unlikely, if you ask me.
 

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I hope it hasn't sat for 30 years with the same oil in it. I do believe I would start by pulling the valve covers, look for valvetrain problems and sludge, clean out what I could by hand with the drain holes covered, use good non-ethanol fuel with a high dose of fuel system cleaner and maybe a good engine flush, fresh cheap conventional oil and a Motorcraft filter for a short time then change the oil and filter again if it runs well. If there is a whole lot of sludge in the valve covers, or in the pan and screen, I would pull the pan and clean it by hand and clean the screen too. And of course, rebuild the engine if needed.
 

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After 30 years a lot can happen. It's a good change the cylinder bores had some rust, the rings stuck. You're probably going to have to pull it apart and possibly rebuild it. However ever I'd run the motor as is and change the oil a few times over a couple hundred miles, maybe even a thousand and see if things improve. Nothing to loose.
 

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Yes, various chemical products through the gas, oil or poured directly into the cylinders have their uses and benefits! MMO, Seafoam, LiquiMoly products or Kreen.
Stuck valve?:shrug: Maybe different places refer it to as different things but to me valves either get burnt or carbon-ed up and hang, lifters get varnished or "sticky." Of course either of those can make your rockers tickitty tappity:wink:
Kreen was the fasted and most impressive snake oil Ive ever drank the kool-aid over whole hog taken to the bank! 6oz into the oil and it quieted a lifter in less than 2 minutes. I think it also loosened my rings of varnish but didn't do back to back tests to prove it. Engine Cleaners

MMO and Seafoam are slower if ever to work on varnish. i think they are most useful in the gas to be burnt in the cylinders.

Google "piston soak."
 

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Years ago when I lived in Vicksburg my neighbor had a chevy that had a bad miss and I took a hammer to the top of the valve and I guess it must have broken up the carbon on the valve because the miss disappeared. Probably just luck but he sure was impressed. Wes
 

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If it was my car, I would:

- Change the oil and replace 1 quart of oil with 1 quart of the cheapest transmission fluid I could find at Walmart.

- Put two bottles of Chevron Fuel System cleaner into the gas tank then top it off. Yeah, some people like Seafoam or other cleaners. In my experience, nothing works better than the Techron stuff that comes in Chevron Fuel System cleaner.

- Drive the car on a long and steady trip.

- Change the oil when it gets dirty, which shouldn't take too long with trans fluid in there. (It's just oil with LOT of detergent)

This won't hurt anything and might help. Won't cost very to much to try. If problems persisted, I would pop the heads, take a peak and see what's going on.

** Make sure your engine is running between 180 and 200 degrees at operating temperature. Nothing sludges up and rusts an engine like running too cold. If your thermostat is stuck open or if someone removed the thermostat, that would explain a lot. **
 

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I like Klutch's advice but if it were actually MY car the engine would have already been out and all apart like last week. :)
 
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A "hot lash" is not applicable to an engine with hydraulic lifters. With hydraulic lifters you just set the pre-load and no need to be hot.
 

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Discussion Starter #14
If it was my car, I would:

- Change the oil and replace 1 quart of oil with 1 quart of the cheapest transmission fluid I could find at Walmart.

- Put two bottles of Chevron Fuel System cleaner into the gas tank then top it off. Yeah, some people like Seafoam or other cleaners. In my experience, nothing works better than the Techron stuff that comes in Chevron Fuel System cleaner.

- Drive the car on a long and steady trip.

- Change the oil when it gets dirty, which shouldn't take too long with trans fluid in there. (It's just oil with LOT of detergent)

This won't hurt anything and might help. Won't cost very to much to try. If problems persisted, I would pop the heads, take a peak and see what's going on.

** Make sure your engine is running between 180 and 200 degrees at operating temperature. Nothing sludges up and rusts an engine like running too cold. If your thermostat is stuck open or if someone removed the thermostat, that would explain a lot. **
HI Klutch

Thanks for the Tranny fluid idea. I had already been advised on that one too. I guess I will try to do the cleaning then the valve adjustment . But It's not time for the rebuild yet.
 

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Tranny fluid is the poor mans Marvel Mystery Oil:grin2: MMO in the gas also makes your exhaust smell minty fresh.
Dont do any adjustments until youve ran a lot of miles on whatever kind of cleaner you choose. Give it a shot to loosen itself up.
 

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If you're going to reset valve preload do it COLD, by the book.

You might want to try a "de-carbon" using tap water first. See the video...

Now, this guy is kind of a wimp.... I use a squeeze ketchup (or mustard... I don't care) bottle starting FULL, and I spray as much water as I can with as wide a throttle opening as possible to keep the engine running above 2,000 rpm.

While this works fine for older, carbureted engines, please resist doing this on modern fuel injected and, especially, turbocharged engines.

Yes, follow up with some carburetor aerosol cleaner after.

 

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Discussion Starter #17
Tranny fluid is the poor mans Marvel Mystery Oil:grin2: MMO in the gas also makes your exhaust smell minty fresh.
Dont do any adjustments until youve ran a lot of miles on whatever kind of cleaner you choose. Give it a shot to loosen itself up.
Thanks "one" I guess thats the best. Its needs to be run now thats its insured. I will put some miles on it for sure.
 
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