Inliners International Forums General Discussion Engines valve seals, 292

I get a puff of smoke at startup, and I'm thinking of replacing the valve stem seals. I read that this can be done w/o removing the head, but I'm not 100% sure of the procedure. What tool do I need to compress the valve spring? I have access to compressed air to keep the valve in place.

Do the intake valve have umbrella and/or o-ring style seals?

thx, Eric

Dear Eric;

That all comes in a kit. Your local parts outlet would know.

I think they came with o-ring from the factory but you could use 'umbrella' ones for an older engine.

Good luck, John M......

Eric

It may not be just the O ring Depending on the Milage It may very well be the guides. The Umbrellas Work Good. For that Matter a little to good Not letting enough oil to the valve. I have rebuilt heads In the past that have had the Umbrellas Which had Burnt valve stems and chewed up guilds because of the Lack of oil to the guide. If you are plaining to keep It long term and this is a High milaged motor It maybe better to have the Head cleaned up and freshen the guides.

Also You can Use a small dia. string/rope In the Cyl.take off the rockers& remove plugs. Put the string/rope into the spark plug hole and Turn the Motor Over by Hand till it comes to a stop This is top dead. Remove your springs Replace O ring Or install the umbrella. Reinstall springs Rotate the block the Opposite way and Take the string/rope back out reinstall rockers & plug And You will be good to go.
Hope this helps }[oooooo]

[QUOTE]Originally posted by Twisted6:
>>
It may not be just the O ring Depending on the Milage It may very well be the guides. The Umbrellas Work Good. For that Matter a little to good Not letting enough oil to the valve. I have rebuilt heads In the past that have had the Umbrellas Which had Burnt valve stems and chewed up guilds because of the Lack of oil to the guide. If you are plaining to keep It long term and this is a High milaged motor It maybe better to have the Head cleaned up and freshen the guides.<<

I had heard this about teflon seals.
I had a head done with teflon seals and pretty much toasted the guides for lack of oil.
This took 10's of thousands of miles, however.
Didn't use much oil though!
Last serious talk I had with a machine shop guy had as a plan teflon seals on the intakes, and stock or maybe umbrellas on the exhaust valves. Anyone hear of, or do, anything like this?

Thanks for the replies. I know it might be the guides, but I'm hoping for an easy fix for the startup puff . I recently bought a '72 C2500, and I'm going to sell this '68. I was hoping the seal replacement would be an easy fix. Good tip about the umbrella seals and the rope trick.

Thanks again.
eric

Yes i have seen and heard of doing both. I have also seen where they run Nothing on the exhaust side But Not something I would do On a street motor. I have also Seen Heads Run with No guides to me this doesn't seem like a good idea Either But I have a head here right Now in my shop That was Built By Crane back in 60s or70s I can't remember what the guy told me when I was first Built But Thats what they did and It also Has No exhaust guide Boss. I have seen this head Run so Who Knows. But Now it's in for a refresh and a Lump port. }[ooooo]

And Your welcome Eric

Is it using oil? If not, just don't worry about it. A puff of smoke on startup is pretty common on a lot of vehicles. My S-10 pickup puts out a much larger than normal puff on startup. I change oil at 3000 miles and it is still full at change time. Joe

Joe, I think I'll leave well enough alone with the seals, as you say. It runs well, and I don't have to add oil between changes.

I finally got the oil bath air cleaner cleaned out and installed. Much better than the stupid 4" chrome jobber .

I'll be sorry to sell it.

Thanks for the help, folks.

As an update to my post, I installed the original oil bath air cleaner on the rig, and the startup puff appears to be gone. Strange.