workhorse st 350 engine smokes

[fstmofo]

New to the site. I just picked up a 2001 workhorse st 350. My problem is that the engine smokes sometimes and is oiling up one of the plugs. This sounds to me like maybe rings and or valve guides. It has a little over 800 hours on it. I have not checked compression yet. It was serviced back in 2009 and valves were adjusted. Compression at that time was 125#. Thanks for any info

[fstmofo]

A couple things that I did not mention
1- There is oil residue in the air box, not on the filter though
2- You have to choke it for abit when first using
3- Seems to smoke after you slow down and then take off again
4- It took let than 1 hours use to foul up the spark plug after I replaced it

[crash12888]

Welcome to BGW!!, you are in need of at least a set of rings.
Plan on a complete teardown and inspection which will include mic'ing the cylinders and crank.
Complete inspection of the head and valves, the rockers and cam are famous for wear.
Pay close attention to the clearance between the rods and crank to reduce noise.
First thing to do is pick up a service manual and do some throne reading.

[fstmofo]

Thanks for the welcome and the info Crash. Do you think its worth the $$$ to repair/ rebuild if needed, or do you think I should look into a motor upgrade? My plan for it is to use it around my property and have some fun too. Unfortunatly, my funds are limited at this time but I want to get the best bang for my buck also.

[kgsc]

fstmoto, just a dumb question but have you checked the oil level ? and is it lifted ? If it is lifted then the mark on the dipstick is wrong. Way too high. I picked up a cart one time also doing the same as yours and it had too much oil in it. Drained it, put 1.5qts and ran it. Smoking almost completely went away after an hour or so.

[ez go go]

Originally Posted by kgsc

fstmoto, just a dumb question but have you checked the oil level ? and is it lifted ? If it is lifted then the mark on the dipstick is wrong. Way too high. I picked up a cart one time also doing the same as yours and it had too much oil in it. Drained it, put 1.5qts and ran it. Smoking almost completely went away after an hour or so.

With compresion at 125 on a 350cc a year ago, with properly adjusted valves, I don't think oil level is an issue. I'm with crash... You need rings and maybe more. We hate to be the bearer of bad news, but usually oil in the breather box is piston ring blow by. Good Luck!

[kgsc]

Not questioning you guys but unless he had changed the oil himself you just don't know.. I have seen people who I thought had a clue put two extra quarts in a car so... Can't hurt to check the dipstick and its free

[crash12888]

You are right kgsc, I forget sometimes and assume the basics have been checked.
Like the guy that didn't have spark and two pages later replaces spark plug and takes off!

You are right to sugest basics and free stuff first!

[kgsc]

Again, I am not trying to question any of the gurus, we just tend to overlook the forest for the trees sometimes. The other thing is the air filter.. It being restricted will cause the motor to pull air from the crankcase and smoke.. I hope it works out for you.

[ez go go]

His comp. just seems way to love for that engine. Facts is facts. Worn rings= low compression which means rebuild. Who knows.. Hopefully when he does figure it out it will be cheap to fix.