Gravely Li loosing power

[SouthamptonBeaver]

Looking for some suggestions on my Li...

The tractor runs well but after 30-45 minutes it smokes out of the breather & looses power?

Oli is fresh and the tractor has a new head gasket.

I do alot of hill & sidehill work with a 30" brush-hog and
it still has the oil-bath air filter.

Ant idea's, suggestions????

Love the old girl and want to make sure I'm not harming
anything

Thanks!

 

[SouthamptonBeaver]

Over 100 views and "0" comments,suggestions or ideas??

Anyone???

 

[oldmech]

Hi! I want help you. I read your thread. Not easy to find. Can be many. First= Check your gas cap. Air must to go in gas tank . Clean the small hole in gas cap. I think this is your trouble . But if not When engine looses power. Stop engine. Remove sparkplug and take compression. If very low as 30-40 lbs. Retight head bolts Torque is 20 lbs. Take compression if low. 2= Valves can sticks or miss clearance . Engine cold check and adjust valves . 012. 3= When you change head gasket is the head in good condition no warped or uneven. 4= May be your engine overheat check fan belt. Good luck ! Oldmech

 

[washita]

I 2nd oldmech, valve adjustment/clearance plays a big role in power especially once engine is warm, I have had valve seats come loose ( alum. block engine) when they get warm, blowback through the carb. when engine was warm due to valves improperly adjusted (cast iron block), not to second guess your mechanical aptitude but did you check the compression after the head gasket was replaced? incorrect head gasket thickness will change compression ratio, could be as simple as leaking intake gasket at the block (fuel mixture leaned out) check your sparkplug for color usually a good sign of internal engine problems or incorrect fuel mixture ratio, my c10 gravely with kohler/241 used to lose power but it was the connecting rod seizing on the crank from oil starvation (tilting the engine more than 15 degrees during mowing)

 

[mt180]

I would say that you have the classic "sticky exhaust valve" issue.

These T-head engines are known for sticking exhaust guides as they heat up.
You can try pulling head and rotating valve with big screwdriver. Raise it off seat first.
Squirt solvent into guide when turning.
If it's real tight, remove valve and buff the stem with a fine polish like brasso.
Clean the bronze guide also. Lightly oil and re-assemble.
Valve should slide up and down VERY easily.