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258 cylinder head question

258 cylinder head question

SarTech

Jeeper
Posts
28
Thanks
0
Location
N.W. Washington
Vehicle(s)
1976 CJ5 stock
Hello Jeep fans,
Im rebuilding a 76 JC5, we have completed the frame and running gear and now starting on the engine. The engine has 53,000 miles on it and has sat for the last 12 years. I plan on putting in new rings and bearings but my question is about the head.
Can I lap the valves and put in new valve seals and be good to go, or do I need to have the head rebuilt with new valve guides due to todays no-lead fuel?

I appreciate any suggestions and guidance.
Thanks much.
Pat
 
Lap the valve and replace the seals.. No need to have them machined
 
check for cracks between the valves. AMC 258 i6 / 4.2l heads like to crack there. you are pretty low miles so you should be good but when you have it cleaned up with the valves out it would be a good time for a Die penetrant test.:D

If you have never done one it is not hard.:D

AIM School- Dye Penetrant Test - YouTube
 
IO and Jimbo thanks you the replies. Im going to lap the valves and replace the seals.
IO thanks for the suggestion, I am familiar with dye pen I did a lot of NDI back in my A&P days.
 

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