01 426 top end advice needed

1 reply to this topic
  • Digger01

Posted March 07, 2011 - 07:50 AM


Hello everyone,

Thanks in advance to any advice because it is needed. Trying to save money so I opened up the beast due to blue smoke, 10 years of unknown maintenance and to hopefully install timing chain, piston and 450 cam. I am the second owner (4yrs) and it seems to be all OEM.
Before disassembly I checked my valve clearance;
Intakes were all 004” with shims of 2-180 and 1- 190 (most left).
Exhaust was .007” with 1 shim-180 and 1-unreadable.
Does my head need work?

The head looks good, seems like no damage in the cam caps or saddles, no sign of the valves hitting. I still need to perform valve fluid seal test. Should I just order valves and seals? Or Send to a shop for new valve seats/seals and valves?
Cylinder little scoured on exhaust side, after cleaning no visible scratches no scouring but I don’t have a bore measurer. Can I just hone this? Send to shop to measure?
The piston seems oem and doesn’t show any sign of hitting the valves. Can I just order new Piston kit (JE) with High compression?

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  • Digger01

Posted March 07, 2011 - 07:52 AM


sorry for no photos but here is a link to photoshop


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