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Valve stem seals

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Recently purchased a 1991 xr 250L. I believe it needs new valve stem seals(smokes about 30seconds after cold start up then goes away). I had a few questions about the procedure. I have a shop manual and have read through it a couple of times, so I have a basic understanding of the job. I am looking for the easiest way to just replace the seals. The shop manual shows pretty much entire disassembly of the valve cover and head, I don't really want to get into that if I don't have to.

1. Can this job be done without removing the head?

2. Can this job be done without removing the cam/cam chain?

3. Can someone explain the air compressor trick, does it work on XRs?

Ideally I would like to use a spring compressor with the head still on the bike and the cam and cam chain still attached, remove the keepers and the springs and replace the valve stem seals, put everything back together and be done with it. Is this possible or do I just need to follow the procedures in the manual and remove the head?

Thanks in advance.

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To do it correctly you will need to remove the head:

I know this is not a dirt bike engine... but it will fall apart the same way.

:thumbsup:

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Might as well pull the head, the bike is 20 years old, probably needs a valve job.

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Might as well pull the head, the bike is 20 years old, probably needs a valve job.

It is an older bike but it only has 2600 miles and runs flawlessly except for a little bit of smoking on startup. I have no reason to think there is anything wrong with the rest of the valve train and really don't want to fix things that are not broken. I am thinking that the valve seals are more prone to aging not miles/hours like the other valve train components.

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runs flawlessly except for a little bit of smoking on startup.

I would still pull the head and inspect each valve, guide, valve seats, etc. It only take 1-2 hours to pull the head and valves. You only have one cylinder so timing is easy.

When I pulled my head, I found out, I have valve guide damage. You want to check these things out now before they get worse. My exhaust guides have chunks taken out of them (previous owner ran the bike low on oil. the oil pump is garbage too; the insides of it broke into pieces.)

This bike ran flawless too when I received it (even with no oil pressure)... just burned a little oil. I'm glad I tore the whole engine apart (see my signature link).

If you want to keep the bike for another 20 years tear it down.

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Okay I guess I will pull the head and check everything out. I checked prices on the parts I would need and it seems to be a better deal to just buy the entire Gasket Kit A from Honda which is $73. I was hoping to just be able to buy the valve stem seals and head cover gasket, but that ends up being like $55. So I guess I will just pull the head. If I do not find any other problems I guess I will just clean the combustion chamber and valves really good and then relap the valves and valve seats.

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