Valve seal info...

[J Banning]

1) What's the difference between "Viton" and "Teflon" valve seals? Which is better? Any special tools needed for the install of teflon seals?

2) What diameter are our valves (intake & exhaust)? I'm guesing they are the same.

3) What is a common diameter that the valve guides (intake AND exhaust) would be cut by a machinist to accept aftermarket guides? MY EXHAUST GUIDES HAVE BEEN CUT.


I know the guides have been cut on my heads. I need to replace the guides (long story) and would like to do it this weekend. I don't know the measurements I need, I'd have to take everything apart. I don't want the car down for more than one day, so I'd rather order two sets and see which one of the two fits.

Link from Summit:
http://store.summitracing.com/defau...pe=bykeyword&searchtype=both&part=valve+seals

Thanks,
-Banning.

 

[J Banning]

No one knows huh? Well, I found a little bit of info that may answer some of my own questions. Here goes...

1) Yes, there is a tool to use for Teflon seals. Sometimes it comes with the seals. It is some sort of simple plastic device for pressing on the seals without damaging them since they are more pliable than rubber seals.

2) Looks like our valves (both intake & exhaust) are the same size... 11/32".

3) The valve seals I would need would most likely be either .500" or .531". Seems like those are common sizes that a machine shop would cut them to.


Correct me if my findings are wrong

-Banning.

 

[snodgrass]

All of your info is correct. I stuck with the factory style seals because from what I have seen in the past, if the guide gets a little loose, it wears the teflon seals out quicky.(not that your guides should get loose anyway if the rocker geometry is correct). The factory seals are much more forgiving in this situation. Lots of buicks out there have over 200,000 miles on them and never had the heads off. Most are still running great with those factory seals. I don't think anyone can say they got that kind of mileage on the teflon style. This is just my opinion, so please, anyone else also chime in. Good luck, Jeff.

 

[salvageV6]

I didn't use the tool with mine, but I did lube them first.

Only been about 20K miles however.

 

[Doug Jacobson]

Viton is just a fancy name for rubber, use lots of Viton O-rings at work. Just a little grayer in color than black rubber ones. I've used Viton with sucess on just about everything. A viton seal will be all black or gray with a ring around the top and one to hold it on the stem. If you are planning on putting seals on all the guides. have the exh. guides cut down at the machine shop to accomadate seals.

Teflon seals ahve a teflon insert around the stem, they control oil too much IMO. A little oil in the valve guide is better than not enough. Stick with regular stock replacemts.

Keep in mind that our cars see positive pressure on both guides at times on the intake and sometimes on the exh. This wil blow oil back up the stem, lessening consumption.

You aren't going to be able to replace the guides yourself, you will have to take it to a machine shop and wait. I suggest having them knurled. This helps to retain oil around the stem and prolongs life, along with saving some $$$.

The seals will come with a little plastic "condom" lube both up and slide the 'condom' over the stem them slide the sel over. The 'condom' keeps the seal from getting damaged on the groves int he top of the valve. Then use an deep socket to push the seal down over the guide. A 1/2" always seems to work for me.

Hope this helps. Doug J

 

[J Banning]

Thanks for confirming my info guys. My parts arrived from Summit Racing today... telfon seals from Comp Cams.

-Banning.

 

[The Radius Kid]

Doug's right,use the condom with oil on it to install the seals.
If you want to use teflon for the exhaust,take the little coil spring off of the neck of the seal[the part that seals the stem].
This makes the seal more "forgiving" and alows a little extra oil onto the exhaust stem.
It's an old trick.
Me,I like Viton rubber stem seals on the exhaust stems[tan brown in colour,although they do come in different colours].
I figure I'd rather replace stem seals when they go bad,than take of the heads and redo guides.
Has worked fine so far.

 

[J Banning]

Thanks again. I'll be nice having valve seals on this car once again... I've been running WITHOUT them since last year(!!). When I did the heads, I put stock one on and they promptly worked loose from the guides.

The smoke is getting a little old, not to mention probably not getting the full potential from pump gas because of added detonation.

-Banning