yanmar1gm.10

[patturner]

help please??
I can run my engine in neutral for 10-15 minutes without loss of power but when I cast off, and run at about 3/4 revs the engine will suddenly cut back to about 1/4 revs. after about 5 minutes.The fuel line has been bled and I can,t find any other reason for the loss of power, any ideas --and thanks in advance

 

[Magic_Sailor]

? being starved of oxygen.
? inside of exhaust pipe has collapsed (not visible from the outside)

Magic

 

[mortehoe]

Q & A session required here:

When you start the engine does it start on the first turn or do you have to crank it for more than 5 seconds?

 

[patturner]

Starts first time every time

 

[lw395]

Partly blocked filter or other fuel line component
Fuel lift pump faulty
Tank Breather restricted
Overheating
Exhaust back pressure

 

[KenMcCulloch]

Fuel starvation seems the most likely. Mine does what you describe (but a bit sooner) if you start it with the fuel cut-off valve (between the tank and the primary filter) closed. If the filters haven't been changed recently that would be a good place to start and if that doesn't resolve it start looking for less obvious blockages.

Let us know how you get on.

 

[andygc]

Been there - mine was diesel bug blocking the fuel pipe as it came out of the tank.

 

[choppy]

Yep me too we had same on 2yr old 1gm it was diesel bug

 

[patturner]

If it is a diesel bug why does it only happen when in gear and under load????

 

[misterg]

If it is a diesel bug why does it only happen when in gear and under load????

Because that's when the engine tries to draw most fuel.

(Look for leaks between tank and lift pump, too.)

Andy