GT-1800 18HP Briggs down on power

[kadetklapp 1]

Now that I've been running my tractor for a couple of weeks, I've noticed it is badly down on power. With the deck engaged and pulling a slight incline, the tractor will stall if you do not either back off the hydro or shut down the mower.

Plugs are in good condition, new coil with wires, good fuel, and the carb seems to be opening up correctly and isn't gunked up or anything. I was told by the PO that the motor had a "partial rebuild" several years ago but I don't know what all was done to it. My buddy thinks the valves may need adjusted. The motor acts like its "loading up" under stress. I've greased my pulley's and everything seems to be turning OK. Any ideas?

[can whlvr 994]

sounds like you need to do a compression test or a leak down test,you can look in the search area or google leak down test,im not very knowagageable of the briggs,i cant tell you if it has the compression release for starting,if it does then compression test is a little harder to do unless you have another tractor to hook up to the pto with a belt ina figure 8 and use the second tractor to turn over the briggs,could be carbon on the valve seats not letting the valves close all the way,you have to pull the heads to check that,unless you have one of those fancy cameras thet can go in the spark plug hole

[kadetklapp 1]

Ok that's sort of what we were thinking as well.

I'm thinking this is a good excuse to do a ChiCom diesel conversion, but the wife unit isn't buying it yet...lol.

[Save Old Iron 1,571]

also check both cylinders are hot

if one is only warm, you might be running on only one cylinder.

[kadetklapp 1]

also check both cylinders are hot

if one is only warm, you might be running on only one cylinder.

That was something else I was wondering, I might have a dead cylinder.

[mavfreak 11]

These briggs are prone to car boning up also. Might want to pull the heads and clean off the deposits while in there you can check the cylinders and valve and valve seats

[Shuboxlover 481]

If this Briggs is like the one on my GT-1642, you might want to check the "fuel pump" diaphragm in the carb, mine was pretty brittle and it would kind of act like you are describing when it was under load. A rebuild kit for the carb fixed my problem.

[kadetklapp 1]

Will do. I bought a can of Seafoam yesterday to try also, just to see if it peps up a bit.

[kadetklapp 1]

Seafoam is no dice. I noticed the thing has a pretty severe "spark knock" type sound to it, and at idle, it is missing and backfiring pretty bad.

[mavfreak 11]

If that is the case then i would say its a very good chance that its carbon ed up.

You'll have to pull a head to check, so you'll need a head gasket.

If it is carbon then you'll need to clean it with some solvent like break clean or carb cleaner. and a wire brush. While you have head off look at the valves close also and make sure one (usually the exhaust is burnt or has a hole in it).

Just something you can try. It has work for me on briggs twins.

[kadetklapp 1]

Ok, thanks for the info.

[kadetklapp 1]

Well it seems the Seafoam helped out a lot with it's idling and start-up power, but I'm still having to back off the stick to keep from stalling it when pulling any kind of incline and mowing at the same time. I'm not sure now if it's the motor, or if the PTO is hanging up.