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Stuck Valve... sheesh!

Morris

Yoda
Offline
Took my freshly rebuilt 1500 Midget for a first drive yesterday. Everything was going great. It was really hard to keep things slow and easy cause I could definitely feel an increase in power waiting to be let loose. Then... thunk. It starts running terribly. I can barely keep it running. I am still in the neighborhood so I limp it close enough to home that I can get some tools and see what's up. Pulling the valve cover reveals that #1 exhaust valve is stuck. I manage to get it loose with a few taps of a hammer and drift. I then work it up and down with a screw driver as lever until it is seated and moving freely. Car runs smoothly again, but I am afraid to drive it.

Does anyone have any ideas how I can prevent this from happening again WITHOUT pulling the head?
 
Had this happen once when I used bronze guides and Perfect circle-type stem seals. Sometimes in our zeal to be oil burning free we over do it, and the guides don't get enough lubrication. My engine builder, at my request, had used seals where there were none originally. When the head gets hot, the guide closes up a tad and with the loss of lubrication, the valves stuck. Removed the seals and all was good, but a little bluer;-) Peter C.
 
disconnect the #1 spark plug... /ubbthreads/images/graemlins/smile.gif


...sorry...

I'd suspect it is expanding with the heat. Too tight clearence on the rebuild? These are new valves and guides and whatnot yes? Was it done by a machine shop with some sort of warranty? I'm just beating around the bush before saying I doubt you're going to get away without pulling the head again.
 
Sadly, I must agree with Mr. Sneddon on this'n.


Ain't THAT a diff'rent thing! /ubbthreads/images/graemlins/devilgrin.gif /ubbthreads/images/graemlins/jester.gif
 
Adjust the valves on the loose side (about 0.018").
Flood the valve guide with something like Liquid Wrench.
Drive it gently for a while.
See if it happens again.
A sticking valve is not that uncommon in cars that sit around a lot.
And it won't really cause any damage if you nurse it home if it sticks a second time (and if it does stick a second time, off comes the head).
 
Worth a try, fer sure. Could have been a tiny bit of "something" got loose in there and caused the problem.
 
Nial wins!

I think the the sticky valve could have been caused, or at least aggrevated by some very rich running. That's a problem that I have solved so... maybe I will get lucky.

Fat chance!
 
"Quit sendin' them ~negative waves~!"

Ommm..... OmmmMani... OmmmManiPadmi.... Ommmmmm....


THERE! All better. Drive th' wheels off'n it!
 
Put some Marvel Mystery Oil in the crank case.(follow the direction on the can) drive the car around a week(a few hundred miles) or so then change the oil. Sounds like ya got a bit of carbon in the guides. Exhaust valves will seize if the guide clearance is too tight. Stainless valves are prone to this problem( greater expansion rate when hot). Usually occurs in racers and lot's o heat.
 
Moris, you didn't do something crazy, like installing oil seals on the exhaust valves did you?
What kind of guides do you have, and what clearance did you get when you had the head done?
Jeff
 
Took her for a short highway drive and she performed flawlessly. Was putting the cover back on her when I noticed a large puddle of oil on the driveway. Looks like fresh gear oil... *sigh*
 
"Big Box" parking lot, teens in an old beater Dodge, LOTS of ATF comin' from it.... Doc says: "Hey kid! Yer car just hemorrhaged all over the floor there!"

---blank look--- "Huh?"
 
Hello doctor,

""Hey kid! Yer car just hemorrhaged all over the floor there!" ",

obviously they were not medical students (or Engish students for that matter!) :smile:

Alec
 
Sad, innit?
 
Ack. Never gave that a thought.
 
I had a friend (who shall remaing nameless) who blew a motor on a car. As he was sitting perplexed at his misfortune, I asked him if he had checked the oil. My friend replied, "Oil???"

BTW, I think I figgerd the source of the oil. Whilst loading the engine/tran back into the car, I had the tran at an extreme angle for an extended period of time. I had observed before that placing the tran at an angle caused the oil to slosh to the back and sit against the oil seal which works fine for keeping sloshing oil in, but is not very effective against a standing pool. The reason I believe this to be the source of the oil is because whilst cleaning up after the install, I had to wash my hair about 5 times to get all the oil out. I remember saying at the time, "I wonder where all that oil came from?"

I'll crawl under there and test my theory when I get off of work this afternoon.
 
mehheh. Remember to put some oil back in!

The transmission, not yer hair. /ubbthreads/images/graemlins/jester.gif
 
Had a roommate with a Celica with the old 20R motor (dang near as bulletproof as a TR tractor engine). Died one day and we couldn't get it to start. I was without manuals but since I was the resident car guru I was put in charge of tackling it. Couldn't get spark. Traced it to no power to the coil. Traced it to a relay under the dash. Went garbage picking and found another relay. Still no spark.

Payday finally rolled around and I made him buy a manual. Discovered that the relay was the oil pressure interlock.

Pulled the dang dipstick out and there was one furry little chunk of dry oil on the very tip of it.

Put in 4 quarts and she fired right up. Drove flawlessly for another 2 years.

Another entry in my mental troubleshooting guide....
 
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