Valve guide oil seals,,, Your help is required.

Can I respectfully ask you guys to stop this shameless thread hijack and bring the subject back onto seals again.

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Hey Bob, I think I recognise that seal. It's an Antarctic Weddell seal called Marilyn. I remember cuddling up to her on a particularly cold night when I camped out on the sea ice off Mawson Station. She never phoned me or returned my messages afterwards - bitch!  >:(
 
Haggis, I've been trying to remember that joke all morning! It was on the tip of my tongue . Reminds me of; " How do you know when you've passed an elephant?
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You can't close the toilet seat. Ta bum chershhhh....

Tim, HTH.
 
Dellortoman said:
Hey Bob, I think I recognise that seal. It's an Antarctic Weddell seal called Marilyn. I remember cuddling up to her on a particularly cold night when I camped out on the sea ice off Mawson Station. She never phoned me or returned my messages afterwards - bitch!  >:(
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My daughters school just said its closing due to weather,very apt! 

Shaun
 
Okay, that's enough messing about, this is a serious thread and Tim needs some sound advice. Tim when selecting a seal don't be tempted to use any old seal, make sure you get one which performs well.






















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This is a true story: When I was at Davis station in 1990-91, we were accommodated in converted shipping containers. They were insulated and fitted out with windows, door, beds, wardrobes etc - quite comfy units. The door was fitted into the side of the container and opened outwards. They also had an escape hatch in the roof in case the door got buried in snow during a blizzard. One morning, one of the guys tried to open the door and it wouldn't budge. He thought this was a bit odd as there hadn't been any blizzard overnight. He climbed out of the roof hatch and found an elephant seal asleep against the door. These animals weigh about a tonne so there was no way he was ever going to open that door while the seal was there.

We figured he was a door seal.  :D
 
redax5 said:
same as Kieth
I fit valve guide seals to inlet and exhaust when I change valve guides, not had an issue yet and have dozens of engines running around set up like that
use custom made Bronze alloy Valve guides and stainless coated valves
works well, so far, no more smoking

I wouldn't fit valve guide seals to a cast iron guide though
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Hi
What clearance do you run between the exhaust guide and valve if you use seals on Bronze guides?
 
sfcpiet said:
Spub,

Smoke on the overrun is quite common, even though the exhaust guides are NOT worn!

The culprit is the excessive countersunk taper at the top of the guide to supply the valve with oil. I reduce this taper by about 80% and the smoking all but disappears. The pic shows the re-worked guide (can be done in situ), the stock taper has an OD of about 9-10mm. It is now under 8mm.

I have fitted seals to exhaust guides with mixed results. Most engines show no issues at all, one engine in particular has seized 2 different valves on 2 different occasions. I have since removed the seals and everthing is tops! Won't be repeating that in the near future, at least not till I find the real cause for the siezures.

piet
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Hi Piet
I have the same issue with the left and middle cylinders they had 10mm od tapers the right cylinder is fine and has an 8mm od taper, I also reduced the tapers and reassembled the engine. The problem persisted after 20 minutes running, I have removed the head and noticed another difference, the offending guides have a groove internally around half way. I have decided to replace the guides and use seals.
What clearance would you advise for exhaust valve to guide?
Steve
 
The RGS
The Three Dellortos said:
Hello Gentlefolk.

Many years have passed since I committed to the FULL and thorough engine rebuild on my 1977 Slater Mirage. I am pulling this motor apart again because it has started to smoke slightly. Rings are new and gapped . cylinder head is RGS with new valves the original has a sizable crack across two valves ......

Here is my question..... The original head has NO inlet valve stem oil seals ..... But,,, when I built the motor using the later head I didn't think and never noticed any valve stem seals.... Does an RGS head have oil seals ?

I thought I had everything covered but I am made of the same material as you lot !

Nice to know yall

Tim
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The RGS parts manual shows 3 x 55 120 063 Valve "gaskets" for the intake valves, but not the exhaust valves. With regard to valve guides, there are 3 different guides standard, 1* rise, 2* rise. Presumably 1st oversize, 2nd oversize.
 
RGS1000RGS said:
The RGS

The RGS parts manual shows 3 x 55 120 063 Valve "gaskets" for the intake valves, but not the exhaust valves. With regard to valve guides, there are 3 different guides standard, 1* rise, 2* rise. Presumably 1st oversize, 2nd oversize.
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That's correct.

No triple left the factory with seals on the exhaust guides nor do the exhaust guides have provision for seals.

piet
 
I fitted inlet guides to the exhausts on TOG, it cost me plenty, the valves seized in the guides and by the time I was alerted to a smokey engine by a following club member the damage was done. On stripping, the seizure was very obvious, but the springs had done their job of pulling the valves AND GUIDES back to the closed position, several million times, so the movement was all interacting between the guide and the head, ruined a very good head, which was then very badly repaired by specialist, I got lucky though and bought and brand new factory RGS head still in its shrink wrap from a Mr.P Todd for a very fair price, built it up and was going again, which is what I should have done as soon as I realized the damage caused, that buggered head did turn into a jig (a big speacer) for doing valve clearances on (another) head using the correct length studs and away from the engine.
CLEM
 
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