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The following are the procedures to adjust the valve clearance. Make sure you have the piston on the compression stroke. When you get the "T" mark lined up, try to wiggle the rocker arms. If they won't wiggle, turn the flywheel one complete turn and stop on the "T" mark again. Now see if you can wiggle the rocker arms. The idea is to be able to wiggle the rocker arms when the "T" mark is aligned. If you can, then you are on the compression stroke and that's where you need to be to adjust the valve clearance.

Here are the procedures. I don't have the service manual for the Fourtrax 250 4-wheeler, these procedures are from the 250 Big Red 3-wheeler manual, but the engines are the same, so this will work for your ATV.


 

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What symptoms present themselves that lead one to look into valve adjustment? My old 94 trx300fw sometimes makes a clicking noise while idling after start up on right side. sometimes sound goes away sometimes not. Could that be valves? How often should valves be adjusted? I have never ventured into valve adjusting and wondered if it might be in order for this old machine.
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Well, I am no expert, but what has caused me to check into a valve adjustment is an abnormal sound for the top end, like a clicking sound. From what I understand it could be from needing a valve adjustment or a timing chain adjustment. I am not sure of the maintenance schedule of how often this should be performed, but my Fourtrax is a 1985 & I do not know when it was done last so I am sure it should at least be checked out. I did read an article on Polaris not too long ago & they recommend a valve adjustment every 100 hours of use. I think it is commonly overlooked.
 

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i never go by hours..or miles..i always go by sound..this is a dead give away if your valves or timming chain need fixing...now..this doesn't rule out that you can use a hour or miles to check them..this is a good plan.. i guess you could say..if you keep it fixed now...you won't have nearly as much trouble later on.
 

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What symptoms present themselves that lead one to look into valve adjustment? My old 94 trx300fw sometimes makes a clicking noise while idling after start up on right side. sometimes sound goes away sometimes not. Could that be valves? How often should valves be adjusted? I have never ventured into valve adjusting and wondered if it might be in order for this old machine.
Thanks.
the reason your valves click when you first start your atv is...when your valves are cold..they do this..when you get them hot after a few min's..they expand...making them higher..which..closes the valve clearance gap between the rocker arm and the top of the valve spring...there is a time frame in your owners manual that should tell you when to check and adjust them...if you don't have a manual..then do what i do...go by sound. if it's '' ticking''..and keeps ticking even after it's fully warmed up..then your valves need adjusting....or your timming chain is streched causing it to slap against the timming chain guides.
 

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The factory service manual recommends checking them every 100 hours.
 

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Thanks shadetree and Helmut. Where do I get the valve wrench that is mentioned in Clymer manual to do the adjustment? Any Automotove store or is it a Honda tool?
all you need is a 10mm wrench..and a screw driver, and a set of feeler gauges.
 
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