2086 issue

[Rex B]

Apparently the engine is running at it's limit for load, due to something not being up to snuff. When you energize the PTO, you are adding load to the engine and pushing it beyond what it is capable of. My first suspicion would be fuel delivery. Those petcocks at the tank get corroded over time. Some have screens that can get clogged. The fuel lines themselves can degrade internally and close off partially. There is also that fuel cutoff solenoid in the carb to consider. Many people just eliminate that.
Someone mentioned the seat switches. Looking at the schematic, there is a lot that can go wrong from the engine to the battery to the PTO, and all the switches in between.
Oak's advice to monitor voltage levels is a good start.
But don't discount the fuel delivery issue just yet. I would remove the fuel line from the fuel pump and lower the end into a bucket to see how fast it runs out.
Lastly, the fuel pump operates off vacuum from the crankcase. It gets that vacuum from a nipple that is above and behind the oil filter mount. It bends at a 90-degree angle and often cracks right there. If it leaks vacuum, fuel pump output is reduced. Replace the hose and try to reduce the bend.

[finsruskw]

Odd, my 2086 has an electric fuel pump, under the seat pan as per spec's in the parts lookup.

https://www.cubcadet.com/en_US/conte...93beb41a1efb/y

[Ian181]

My friends 2086 is under the seat also.

[Rex B]

Originally Posted by finsruskw

Odd, my 2086 has an electric fuel pump, under the seat pan as per spec's in the parts lookup.

Sorry, I just assumed you had the same Kohler drivetrain as my 2084

[Ian181]

Rex, no problem, I appreciate your imput.

[finsruskw]

Look for a kink in the fuel line just prior to the fuel pump. There is not much room in there for plumbing!
The parts lookup call s for TWO filters,(WTH!) the one by the pump and a second downstream just short of the carb. Mine only has the one by the carb.

[finsruskw]

Look for a kink in the fuel line just prior to the fuel pump.
It makes a pretty sharp angle there from the dual tank feed to the fuel pump.

The parts lookup even shows a filter there just ahead of the pump, which mine did not have BTW, and there is not a heck of a lot of room in there for plumbing! Mine was down stream on the right side of the engine just shy of the carb.

[Steve N Mi]

Originally Posted by darkminion_17

We assume that the fuel lines and fuel tank shutoffs are free flowing?

In my experience I wouldn't assume that. The shutoff valves #3 can be a problem espically if water is allowed to sit in the fuel lines at that point. They are made of steel and can rust causing restriction to fuel flow. I've seen where they have rust particles at the needle seat (or close by) that move around some depending on fuel demand making it difficult to pinpoint them as the problem. Because they have been an embarassment to me in the past (didn't eliminate them as potential problem) I would check them out. Look for full flow from the tank with the gas line removed. Open and close them a few times if you don't see a good flow but if that changes the exit stream - replace the valve. I have repaired some #3's but that's another story.