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JKMTRS 6 Jul 2021 20:19

1990 XT600 Head / Cam Journal Repair
 
I picked up an XT600 with 11,000 miles. I took the head off and the cam and head journals are scratched. In some older post (https://www.horizonsunlimited.com/hu...cam-worn-53548), I saw suggestions to 1. TIG weld the journals and have them machined, 2. machine the bearing bore and insert metal replacement journals or 3. use bronze journals.

My question is, are there any recommendations for shops in the U.S that can fix my scored cam and head journals?

Thanks
Jim

turboguzzi 7 Jul 2021 14:48

post pics of those "scratched" journals

unless you have previous experience and know what you are looking at, you might be worrying for nothing.


second, if journals are indeed bad, it could just be just tip of the iceberg, what about the rockers? and very likely oil pump is bad (didnt send oil to head) and the reason is often gearbox debris that detroyed it.


lets see some good pics, then I can give you advice, in such a case, IMHO its wrong to give an opinion without seeing, you might not need a repair in the first place...

Mezo 8 Jul 2021 07:30

Quote:

Originally Posted by turboguzzi (Post 621310)
post pics of those "scratched" journals

What Turbo said.

Besides even if they are bad (doubtful with that low milage) it would be cheaper to just buy a used head off ebay rather than trying to repair yours.

Mezo.

JKMTRS 9 Jul 2021 00:34

1990 XT600 Head / Cam Journal Repair
 
2 Attachment(s)
Attached are pictures. The outside journals on the cam are more worn and the left most journal on the top/bottom of the head.

If they aren't worn enough for machine work, do you recommend any "clean up" or other treatment?

Thanks

turboguzzi 9 Jul 2021 08:24

thats an ok condition head in my book



maybe take a pic of the most worn area you are mentioning, both head and cam, hard to see them in these bigger pics.


was there any specific reason you took the valve cover off? like noise or was it just paranoia ? :)

JKMTRS 9 Jul 2021 14:06

1990 XT600 Head / Cam Journal Repair
 
3 Attachment(s)
More pictures - the cam chain side journal; top of head, cam and bottom respectively.

I took the head and cylinder off because the engine wouldn't rotate. I probably didn't try hard enough though because the cylinder came off without much struggle after the head was off. Machine shop bored cylinder +2.00mm (to 97.00mm) and I got a new piston. Shop said they couldn't fix head, but I am thinking something can be done with it versus getting replacements (I am not going racing and it is an old dirt bike).

Thanks for the feedback.
Jim

N67 9 Jul 2021 20:28

can't do any assessments.
in long term, just wanted to suggest using magnets - at least on the oil drain plug (fastest and easiest).
so far can't find that topic, but i do remember from this forum that it is also doable just below oil pump (with flat hdd magnets). this option should be the best.

Mezo 10 Jul 2021 08:04

That`s not normal wear, its starved of oil.

Mezo.

JKMTRS 10 Jul 2021 12:51

1990 XT600 Head / Cam Journal Repair
 
Correct.

What do I do about the scored journals?

Thanks

turboguzzi 10 Jul 2021 23:44

I know this isn't the answer you want to hear, but ask your self WHY it was oil starved.

Don't know any machine shops in the USA to do the work, one I know locally would simply mill the journal deeper with a spherical bit and then take a lick of the mating head to cover surface to restore clearance. No need to weld



But like I said in my first Post, question is why it got oil starved, you need to check and solve the roo9t cause.,

JKMTRS 11 Jul 2021 00:28

1990 XT600 Head / Cam Journal Repair
 
Thanks, I will look into your suggestion.

Regarding root cause, I'll investigate. I suspect, the owner let the oil level run low, but will look for other evidence.


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