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sticky valve
https://www.slantsix.org/forum/viewtopic.php?t=10332		 Page 1 of 1
Author:  sixty4dartgt [ Mon Sep 06, 2004 10:11 am ]
Post subject:  sticky valve
I got my engine back together after the head work and new Comp 252 and timing chain. NICE! :lol:
One thing is the #4 exhaust has lost the rod twice now.
The first time was when I started it up after I had set the lash cold. I kept the cover off and my timing was also way off (I had it 180* out), so I thought it was just a back fire that knocked the rod off.
The second time was after I got everything together. I ran it up on the freeway and when I got off of it, there was a miss. After I got home, I pulled the cover and the #4 exhaust rod was off (and bent). :x
I found that the valve was partially down. It popped up easily with a little tap.
I put it together (with a new rod) and no problems, but I've been going easy (3,000-4,000 rpm).
I think it could be a clogged rocker arm. Another thing is, that the rocker arm is not exactly centered over the valve.

Any thoughts from the vault of experience the is Slantsix org ?? :wink:
Author:  relic-lover [ Mon Sep 06, 2004 12:20 pm ]
Post subject:  stuck valves - bent pushrods
When I had this experience the valves stuck due to bad gas. The bad gas
left deposits on the valves and frozen them in the guides. Since yours is
a new engine there should be no deposits on the valves.

The clearances on the sticky valve could just be on the tight side.
Anything that causes that valve to run hotter will make the problem
worse. So make sure the oiling to that valve is good, keep the fuel
mixture away from lean, keep the valve adjusted a hair to the loose
side (more seat time is more cooling time). Watch the engine temp.

If the trouble continues you may need to check the valve and guide.
Then replace the valve or have the machine shop open up the guide
to get the valve to guide clearance in the middle of the range.
Author:  Craig [ Mon Sep 06, 2004 12:44 pm ]
Post subject:  Re: sticky valve
Quote:
Another thing is, that the rocker arm is not exactly centered over the valve.

:wink:
Do you have the spacers under the rocker bolts in the correct locations? The center one is longer (wider) than the others. Check that.
Author:  sixty4dartgt [ Mon Sep 06, 2004 5:55 pm ]
Post subject: 
OK Thanks for the info. The spacer might be it 'cause I had 2 bolts fall out while the rocker assembly was sitting on the shelf. I'll check it out.
Author:  sixty4dartgt [ Sat Sep 11, 2004 3:38 pm ]
Post subject: 
The spacers were off. Thanks again. :)
Author:  sixty4dartgt [ Mon Oct 18, 2004 5:08 pm ]
Post subject:  Another valve this time
OK I've got another valve sticking (stuck). This time it's worse.
The #6 intake bent a rod. I went thru the same procedure as before. The valve will not come up all the way this time. I put a large deep socket with extention on it, and hit the end with a hammer. It moved, but will not come all the way up.
Anyone know any tricks before I pull the head off?
I checked my plugs and I'm not running lean (probably rich).
I had the valves just done with new seats and guides.
I ran the engine up to about 4800 rpm when it happened.
Thanks for your help.
Author:  mszauner [ Mon Oct 18, 2004 7:29 pm ]
Post subject:  This worked for me
Someone here suggested this to me and it worked. I removed the valve spring and put the valve stem in a drill chuck, oiled the stem and let the drill spin it a bit. Be careful when removing the spring so the valve doesn't drop into the cylinder. You can put air pressure into the cylinder with an adaptor, or stuff a rope in through the spark plug hole.
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