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Testing Valves/head with WD-40

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So i pulled the head off my 05' crf450r. There is damage around two of the vavle seats as you can see in the pic. I put the head on a level surface with a towel underneath and sprayed a good amout of wd-40 into the intake and exhaust ports making sure to get the wd-40 into all 4 valves. Its been a few hours and no fluid has leaked out at all..Doesnt this mean the valves are sealing properly??

I was considering buying a used head. THe head is bare except for the valve guides which are still in the head. The valve seats all appear to be in good condition.

Does anyknow know if i can pull the valves, springs, and keepers from my old head and put them in the used head??

Would i have to the seats recut with the used head and install new valves??

As you guys can tell, im looking for the cheapest possible route out for right now untill i can come across some more money and have a head rebuilt or install a new one..

Here is the pic of the valve seat damage..

102_1321.jpg

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I would also like to know, can you just have the seats re-cut and install/lap the valves yourself? This would save a little cash since its only about $20 to get each seat cut and you can get a pro-x SS intake valve kit and stock exhaust valves for under $200. ?? am I missing anything here?

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This is the same post from a few weeks ago.

You need new seats installed in that head. Either do that or buy a new head ready to run. either way you are looking at about $600

spray carb cleaner down the intake/exhaust and it will leak for sure.

you can see damage on the rest of the head from the intake seat piece there bouncing around the combustion chamber.

Used parts in a new/used head? only if you want to waste your time and grenade your motor.

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So i pulled the head off my 05' crf450r. There is damage around two of the vavle seats as you can see in the pic. I put the head on a level surface with a towel underneath and sprayed a good amout of wd-40 into the intake and exhaust ports making sure to get the wd-40 into all 4 valves. Its been a few hours and no fluid has leaked out at all..Doesnt this mean the valves are sealing properly??

I was considering buying a used head. THe head is bare except for the valve guides which are still in the head. The valve seats all appear to be in good condition.

Does anyknow know if i can pull the valves, springs, and keepers from my old head and put them in the used head??

Would i have to the seats recut with the used head and install new valves??

As you guys can tell, im looking for the cheapest possible route out for right now untill i can come across some more money and have a head rebuilt or install a new one..

Here is the pic of the valve seat damage..

102_1321.jpg

The W/D-40 test should work, you still should check stem/guide clearance though.

as for the seat damage...how can you tell? it could be just carbon flaking from what I can see with valves still in.

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