hey guys i just bought a 97 400 foreman 4x4 that needs brakes and smokes really bad ...it is kinda rough yet has brand new wheels and tires on it.. needs some plastic maintenance and a little TLC ..it seems to run and shifts fine.. the best part is i only paid 500 dollars for it.. the guy i bought it from said he thinks it needs a new top end / maybe rings and pistons .. i am clueless .. where should i start .. and was this a decent buy..

 

First thing I'd do is go to Harbor Freight and buy a compression tester, and test the compression of the engine.

http://www.harborfreight.com/c...m.taf?Itemnumber=95187

Clean the area around the plug, remove it; screw in the tester, wind the engine over a couple seconds and read the gage. 100 or better on the gage is good. If lower, squirt a little motor oil in the hole and test again. If 100 or better now, valve seals are probably shot. If still below 100, rings are probably shot.

My best guesses.

 

The 400 will read low on compression because of the decompressor. I think spec for cranking compression is around 70. Backing off the exhaust valve lash adjuster will show the true compression while cranking over the engine, holding the throttle wide open.

 

Once again I bow to Gimpster.

 

You pointed him in the right direction though...

----- Gimpster -----

 

thanks guys i appreciate it .. if i have to rebuild the whole engine .. is that a big expensive job.. i aint no master mechanic .. but i can turn a wrench..and i also have friends.. or is it worth paying an atv mechanic .. like i said dont have alot of money in it and it is just a beater for the hunt camp .. but i want it to run