yanmar seems to be skipping

buntrock · Jun 23, 2009

I just repaired my Yanmar1700 replaced rings rod brngs head gasket,but now it seems to have developed a skip while running . It is not constant sometimes it does sometimes it doesn't.I did not tamper with injector pump or related mechanicals during repair.It idles as it should just at random while using tractor it skips.I installed new filters fuel oil and air and have primed,injectors several times.It has water pump,'Hoye Tractor," and new radiator oil pressure and temp gauges.Temp runs around 190 while operating and oil pressure around30 psi.Everything seems normal,have not checked compression however appears to have normal or adequate compression.Have added ,'Sea Foam," additive,recommended by local mechanic,but have noticed same random skip. Have less than 1hr on re-ring. Any suggestions?

mikereid · Jun 23, 2009

There is a yanmar section in this forum group and the guys there might be able to help you out better.

The oil pressure seems low. My oil pressure runs about 50 psi when at about 190 - 200 deg.

Also check all the fuel lines from the fuel tank to see if brittle, they may have small cracks in them letting air in the system.

clytle374 · Jun 24, 2009

That really sounds like air being sucked into a fuel line.

Seafoam works great, but IMO only when used in a small tank like a 2 liter Coke bottle mixed %50 with diesel and the supply and return lines in the bottle.

Iplayfarmer · Jun 25, 2009

clytle374 said:
That really sounds like air being sucked into a fuel line.

Seafoam works great, but IMO only when used in a small tank like a 2 liter Coke bottle mixed %50 with diesel and the supply and return lines in the bottle.

How is that different than putting a 50% mixture in your tank?