Valve Guide Question

[Anonymous]

I'm planning on replacing my valve stem seals soon. How do I know if my seals are good? I've been told to check them for play, is there any play allowable if you move the valve side to side?--Or should they be rigid?? Thanks...

 

[Anonymous]

I assume you meant the guides and not seals when talking about play. There should not be any play between the guide and valve stem. The guide acts as a bushing. If there is any play, it breaks the seal between the valve stem and the seal. If the head is going to be off the car anyway, replace the guides. Its cheap insurance, at $2 a piece and the labor is probably included in the valve job. Some other considerations: heardened exhaust valve seats for unleaded gas, teflon valve seals from ford six parts (they are only $15 vs $12 for stock umbrella type and last much longer)

Hope this helps
Dan

68 mustang 200 under construction

 

[Anonymous]

Hello, stang

I agree with dan on all points

technical note: valve stem to guide clearance( rule of thumb).
.001"- .003" on intakes & .002"- .004" on exhausts.
This is the acceptable range and you should have no problems staying on the tight side of these specs.

Machine shops vary in their methods and pricing. Where I work, we itemize the different operations.

Here is approximately what our shop charges:
Basic valve job $110.00
Replace 12 guides $100.00 guide inserts: $3 EA.
Machine 12 guides
for "good" seals $45.00
Install hardened
exhaust seats $75.00 seat inserts: $5/$6 EA.
Mill 6 cyl. head $44.00

Good luck, Ron