MF TO35 with Z134 falls flat after engine heats up

The kid · Dec 12, 2015

I had a problem similar on my 65 gas Continental. It was missing the exhaust manifold heat shield and was vapor locking when it got hot using it brush cutting. The heat shield is difficult to get loose and reinstall. Many farmers throw them away. In other words the fuel was boiling and causing the carb to lose prime, sputter and die. I put a used heat shield on it with mods to make it easier to install and no more vapor lock. Could it be? OR you may have governor issues with the linkage.

Drdan524 · Dec 13, 2015

That is what I feel it is doing. The steel fuel line rotted out so I replaced it with rubber except on the ends where it threads into the sediment bowl and carb. Plus there is an exhaust leak blowing right at the carb. So I am going to try and put the new exhaust on today along with a couple other things while we have nice weather here in New York.

The kid · Dec 14, 2015

Does your exhaust manifold have a heat shield on it. The heat shield uses the same studs and mounts on the exhaust/intake manifold. It's a real b!tch to take off and put back on. So when a leak in the manifold occurs, it seems many throw the shield away. I bought one at a tractor salvage years and modified the bolt points to make it easy to remount. I found all my pictures on a thumb drive when I restored my 65 135.

As for the fuel line. It passes very close to a 500 degree source. I would invest in or have someone make you a new steel line. I bought a fuel/brake line bender at Harbour Freight and a tube flaring kit used off ebay and duplicated the fuel line path. I did the same as you did at first and caught h@ll about it here because of safety. The more I thought, they where right and went back with a metal line from the carb back to the sediment bowl.

Drdan524 · Dec 19, 2015

I do have the heat shield on my engine. I also purchased a new line to run from the sediment bowl to the carb. Tomorrow I will put everything together and post an update. Thank you guys for the help!

Drdan524 · Dec 20, 2015

Ok, so I did most of the repairs today. Machine ran well but still fell flat. I put the new fuel cap on too. I did notice that once the machine lost power, I heard the gas bubbling inside the tank. I have the heat shield on the engine and I didn't feel any hot spots around the tank. If I remember correctly, there used to be heat resistant padding on the bottom of the tank where it goes around the valve cover wasn't there?

Jerry/MT · Dec 25, 2015

Have you checked the screen in the fuel elbow at the carb fuel inlet?

The kid · Dec 26, 2015

Show us some picture of how the fuel line is run from the sediment bowl cutoff to the carb. The screen mentioned is located inside the tank and can be removed by unscrewing it. The screen is about the diameter of a #2 pencil. By switching to reserve fuel is level with the screen. Heat changes the liquid fuel to a gas and blowing out the float thus a sputter and stall. If the gas line get too hot routing near the manifold the gases created in the line is clearing the carb. I had insulated padding under my tank, but later found a shield and took the padding off. In a nutshell it is important to have the steel fuel line routed correctly and well clear of rising heat from the manifold.

If the heat shield is still in place, and you don't want to make a new fuel line, you buy some flameproof wrap from an auto parts and wrap the fuel line to prevent cooking it.

A lot of owner will route their exhaust vertical because of the huge amount of heat rising off the manifold when you are in low range with high RPM's. I would bet this shutdown only happens going slow with high RPM's.

Drdan524 · Feb 2, 2016

OK, sorry it took so long to reply. I got busy with other projects. The sediment bowl is brand new and the screen is new as well. Fuel line is brand new, exhaust pipe is new because the only one was spitting oil as you will see in the picture. I cleaned the inside of the carb and replaced the head gasket which seemed to be the cause of the oil in the exhaust. But after about 15 minutes of running I hear the gas in the tank bubbling. The fuel cap is also brand new.