Hi Everyone, this is the first time I’ve posted a technical question on the H.A.M.B. so my apologies if I’m not as clear as possible. Here goes. I’ve got a 1961 Chev Belair with a 283 with Canadian cylinder heads. The engine has had two overhauls in its life but I’m not sure if what work was done to the heads if any. The car started to foul a couple a plugs a while ago and puff a little bit of blueish smoke on start up. I bought a 16 rubber umbrella seals and installed them with the heads still on the engine. I used one of those screw type spring compressor.That’s where I think I made an error. When I installed the seals, I pulled the springs off the valve over the original o ring and if it broke I didn’t replace it. Luckily the only ones that broke were on cylinders 3 and 7 on the intake valve. When I started the car the smoke was worse and I burnt nearly a quart of oil in a little under one hundred miles but I did manage to kill a lot of mosquitoes. I bought 16 valve stem o rings and installed them on all valve stems, but I put the o rings on and then very gently pushed the valve spring and the part the sits over the top of the spring (sorry, don’t know what it’s called) over the o ring after lubricating liberally with engine oil. Put it all back together and I still get smoke after decelerating but not as bad. Have I stuffed up the o rings? Or is there something else that causing the smoke. The heads may need new guides but I don’t drive it much and I installed the umbrellas and o rings to try and delay getting the heads overhauled. Could a leaking intake gasket also caused symptoms similar to failed valve stem o rings? I appreciate any advice that you could give me and will post updates if I get a solution. Many thanks in advance. Mark. (61Cruiser)
Those umbrella seals should have fixed your problem if it was valve stem related. You don’t need the O-ring seals if you’re using umbrella seals. You would need to make sure the umbrella seals are not getting damaged by the valve springs when the valve opens. Sounds like it’s burning oil for some other reason. Possibly the intake manifold is not sealing correctly to the head at the bottom. Sucking oil from the valley into the cylinder head. That’s what I would check next.
It could be me but I find it hard to understand how you wrote you did this repair. Did you use the plastic sleeve thats sometimes supplied with the seals to get them over the valve stem keeper grooves that prevents destroying a new seal ? Are the oil returns in the head clogged ? Also, if a lot of oil has collected in the mufflers, it wont burn out easily.
Oring seals go on the valve stem after you compress valve spring/retainer. IE. Compress spring/retainer-install over valve-install orings-install locks-release spring pressure. If the umbrella seals are not quite the right ones at full valve lift they can act like an oil pump and actually push oil down the guides into chambers. Make sure they dont fit tight over the valve guide boss/casting. And just for curiosity, never heard any Chevy heads refered to as Canadian heads. Is that a thing?
this. The spring retainer (the big round part with the tapered hole in it) has to come up from the bottom to "cover" the O ring, after you put the O ring in it's groove. Just for fun, have you done a compression test on the engine?
Some reading and pictures here. Just some more info. https://www.jalopyjournal.com/forum/threads/sbc-valve-seals.1009467/
Hi Kev, thanks for the info. I always thought that the umbrella seals made the o rings unnecessary but that apparently only applies to the positive seal umbrella type. I’m using the soft rubber, “ford” style so still need o rings. So I’ve been informed.
Hi “garyf”, I’m only using the rubber “ford” type umbrella seals so did not have the little plastic doohickey that comes the positive GM type seal. I checked the drain back has as you suggested as they seem clean. Thanks for your reply. Every bit of info is useful to me. Cheers.
Hi “Oneball”, I’m really hoping I can put off getting the guides done. It really wasn’t smoking that much before I started all this, now wishing I hadn’t.
Hi “Pav8427”, thanks for your reply. I have gone back into the garage this morning and pulled the valve springs again and have followed the instructions that you and @squirrel suggested. I’ve done 4 out out 8 cylinders( exhaust and inlets valves) and on two of the inlets I found that I had pushed the o ring out of the groove when I previously installed. After following your instructions I’m confident that the o rings are in the groove. I’m going to finish up the rest and I’ll post something here on the results. Thanks to you both, and really to everyone for their responses. The H.A.M.B. is brilliant for getting information on these old cars and engines. Also in answer to your question on Canadian cyl heads. This car is an Australian “assembled” Belair. That means it was “built” as a right hand drive car in Canada as kit (CKD= Completely Knocked Down) and shipped to Australia and the “assembled” here by GMH (Holden, a GM brand here in Australia) The cyl heads have cast into them CANADA and have a casting number that I have never been able to get solid info on. I’ve been told they are truck heads with 60cc chambers and small valves. I’ve attached a couple of photos. Cheers and thanks again.
Hi “sdluck” thanks for your reply. If this doesn’t work, the intake gaskets is my next step. Cheers and thanks again.
Hi “Algoma56” thanks for the info. I checked out the thread at it confirm was what @Pav8427 and @squirrel posted. It confirms that my first installation process for the o rings was wrong. As my earlier post shows, I may now have the problem solved. When I finish up the last 4 cylinders I update this thread. Thanks heaps again everyone. Cheers.
Yes , Especially in NZ where our Chevys and Pontiacs had 283 engines with different casting numbers. They weren''t special All these engines had blank [non-script rocker covers] The whole thing was a tax loophole in the 60's with NZ and Canada both being British Commonwealth countries Here is a 283 engine I pulled from a Canadian Assembled RHD '66 Impala It had 1816887 "Canada" on the castings
Hi “Kerrinzl, has that engine got staggered valve cover bolts? That’s also something unusual about these heads. I’ve been told that long after GM started using parallel bolts, these heads still had staggered. I managed to pick up a pair of “Chevrolet” raised script staggered bolt covers for my car, which I had chrome plated of course, ‘cause chrome will get you home! Cheers
That engine shown had straight bolt pattern on the rocker covers Staggered bolt heads were 1955- 1958 [some say mid 1959] With your 1961 Chevy, if it is factory RHD it would be Canadian assembled [or Aussie assembled from a CKD out of Canada] so it could be possible to have oldish castings. Check the casting dates on both heads ,AND the block and it will give you a clue.
Learn something new every day. How about some pics from different angles. What ever you can get. Maybe the shapes casted into the ends of the heads will give more clues
The plastic "doohickey" would be for all types of valve seals for all makes of cars. To prevent the seal being destroyed being pushed over the valve keeper groves. A piece of wax paper wrapped around that area could be a substitute for the doohickey..
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