HarleyTechTalk

I just installed a Andrews #1 cam and pulled the front head to check the upper valve spring retainer to valve stem seal clearance.  Well I didn't have enough, it is .435 on a .427 lift cam.  I used James seals 18000-81 and they have a really tall body.  without the seals there is .750 clearance from the valve guide the the upper spring retainer.  The top of the valve guide is .250 above the lower spring seat.   Could you guys recommend a valve stem seal that would fit better. Valve guide O.D. is approx .623 Thx, Tom

.435, seal to upper retainer clearance.
.750, guide to upper retainer clearance.
.250, top of guide to lower spring seat.
.623 valve guide OD.

Pic of the James seals.

  This is an '84 isn't it?  The lower collars should be the wider inner hole style, where the whole collar sits around the guide base. You should have a lot more room than 1/4" to press the seal onto?  If not, you may have early 80's collars that fit around the 5/8" part of  the guide. You could grind off the inner rim of the collar if you don't want to buy a set (but you should), of later lower collars, and that'll give you room to push the seal farther down. Show a pic of your head & lower collar type together.

I'm at work now will get a pic when I get home.

Someone may have also used the earlier guides, they're a bit longer than the later guides.


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The spring seat needs the counterbore to clear seals, then they sit down. I put those collars on a machined flat so they dont rely on the guide flange for support. Adds lift potential and further increases seal to retainer clearance. Aftermarket spring kits already have the lower and seal counterbore,  stock parts can be machined.  I use a special collet.

Quote from: jeffscycle on December 13, 2019, 12:34:01 PM
  This is an '84 isn't it?  The lower collars should be the wider inner hole style, where the whole collar sits around the guide base. You should have a lot more room than 1/4" to press the seal onto?  If not, you may have early 80's collars that fit around the 5/8" part of  the guide. You could grind off the inner rim of the collar if you don't want to buy a set (but you should), of later lower collars, and that'll give you room to push the seal farther down. Show a pic of your head & lower collar type together.

Yes it's a '84.  Here's the pic, I have the correct spring seats.  The Viton seal is too big on the OD to slip through the spring seat, someone on the Shovelhead forum said I may need to open up the spring seat ID to correct this.  I'm going to think it over, I may use OEM K-line seals, they fit fine.

Stock K line seals work just fine

On my 82 i used Andrews lower collars with Cometic valve seals. I had to slightly open the lower collar to slide over the seal. I got enough clearance to run a Andrews #2 cam.

Those seals shown will not clear the ID of the collar. You can open it up or use Klines

Quote from: guppymech on December 13, 2019, 08:48:36 PM

Quote from: jeffscycle on December 13, 2019, 12:34:01 PM
  This is an '84 isn't it?  The lower collars should be the wider inner hole style, where the whole collar sits around the guide base. You should have a lot more room than 1/4" to press the seal onto?  If not, you may have early 80's collars that fit around the 5/8" part of  the guide. You could grind off the inner rim of the collar if you don't want to buy a set (but you should), of later lower collars, and that'll give you room to push the seal farther down. Show a pic of your head & lower collar type together.

Yes it's a '84.  Here's the pic, I have the correct spring seats.  The Viton seal is too big on the OD to slip through the spring seat, someone on the Shovelhead forum said I may need to open up the spring seat ID to correct this.  I'm going to think it over, I may use OEM K-line seals, they fit fine.

k-line seals are fine to use, I agree with the others. Keep it simple.

I ordered K-line seals, Thank You one and all for sharing your knowledge!  You guys are Great.

Tom

   The k-lines would make things absolutely easier, and odds are you'd have no problems with them coming loose. I think the OEM got in a hurry when they used them, and had about a 50% failure rate back in the day. They used them for one reason only, they're cheap! If you were compelled to use Viton types, you could open up the upper portion to the collar to the guide's step & leave the base alone, you'd have to assemble the collar on first before the seal. OR if you have access to a 9/16" guide cutter to the use Pre-79 seals.
   
   For the cam your using, you won't have any travel issues, but if you were to try something with taller lift, I'd be leaning towards a trimmed guide & Viton.