Mangled Head

10 replies to this topic
  • smdonald

Posted March 02, 2008 - 10:42 AM


So i got another 426 from a guy who owed me money but the thing is not going to get it going again but i need quite a large amount of parts...

What happened to it was the cam chain slipped due to exsessive wear and stretching and the piston smashed 2 of the exhaust valves. one broke off and embedded into the top of the piston. As the engine wound down after this catastrophic failure, the valve that was in the piston hit center of the cylinder between all the valve seats.. its pretty gouged but the head doesnt look to be cracked.

Is it safe and/or practical to try and clean up the old head and try and use it again?? New heads are around $550 and im trying to get by w/o buying one.

What do yall think??

  • sirthumpalot

Posted March 02, 2008 - 10:53 AM


There are some machine shops that specialize in head repair, send it to one of them for evaluation. :smirk:

  • Kent Rathgeber

Posted March 02, 2008 - 02:01 PM


I don't think I would take the chance on that used head. I'd go with a new one, since you need new valves, guides, springs, seals, piston, rings, anyway. The killer for me was that the valve was rammed into the head by the piston, according to your post.

Grayracer would know better than I do, so hopefully he'll chime in with his advice.

  • tnl

Posted March 02, 2008 - 03:14 PM


New one!

  • William1

Posted March 02, 2008 - 03:25 PM


Replace the head. Trying to salvage it will probably be a continued nightmare.

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  • smdonald

Posted March 02, 2008 - 05:18 PM


i have the same thoughts on using the old head. it might be more trouble than its worth. i looked at it closer today and the gouges go into the seats for the valves...not sure if that can be repaired??

my guess is try to find a used one off a parts bike...

  • grayracer513

Posted March 02, 2008 - 08:46 PM


Send the head to Millenium Technologies or EDCo. They fix stuff just like that all the time, and if it won't work out physically or economically, they'll tell you.

  • Birdy426

Posted March 02, 2008 - 08:51 PM


Engine Dynamics is another first rate shop that repairs this kind of damage. You also might try e-bay for used ones, and also check out Eric Gorr's web site in the "Garage Sale" section. Sometimes he has soe killer deals on older stuff. You can use a head from 98-02, though the 90 and 99 400 heads take a little mod. If you end up with one of those, PM me and I can give you the poop.

  • grayracer513

Posted March 02, 2008 - 09:08 PM


Engine Dynamics Company, LLC, is EDCo.

  • Birdy426

Posted March 03, 2008 - 12:46 PM


Engine Dynamics Company, LLC, is EDCo.

Thanks, I had not heard them called that before...

  • smdonald

Posted March 03, 2008 - 08:44 PM


i called milenium today, repair and valve job 600 bucks, called EDCo, repair and valve job 450. not as cheap as i thought. still beats a new head.

i think i'll shop around for a used one. i cant find any on ebay or craigslist. maybe someone knows of a salvage yard????

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