Yanmar loses power, slows down & kills

California · Feb 2, 2008

ToadHill said:
Just a thought, are you sure none of the fuel lines have collapsed. I've had rubber fuel lines that look good on the outside but collapsed on the inside. It was a heck of a problem to diagnose.

... but he said he had the same result fueling it from a temporary tank with its own hose. The injector pump inlet banjo was the first 'old' part that the new fuel reached.

tallyho8 · Feb 2, 2008

tractorErnie said:
Toad, thats what I thought was his problem too. The fuel lines are falling apart from the inside or the tank was dirty & clogging up things. I wish he lived closer I would pack up the truck & drive there, though Im in Oregon & he's in Florida

Heck Ernie, I'm in Louisiana not Florida. That's at least 100 miles closer. You could make it here in no time.

Besides, Mardi Gras is Tuesday so if you hurry I will guide you around to the Mardi Gras festivities and after we recover from the hangover we can fix my tractor.

Like I said. I installed all new fuel lines and filters and even changed tanks temporarily with no change. Swapped injectors, no change. It still starts immediately and runs perfect when cold. After it runs 10 minutes it stops running on cylinder #1 and barely runs on #2 and runs ok on #3 for a while until it kills altogether.
I'm reading the service manual on injection pumps right now, trying to figure out if this is the problem. I just wanted to make sure it isn't any of the little things before I get a $1000 injection pump job.
The hardest part is that it runs great when cold so it must be tested hot and if I get the necessary equipment to check the injection pump I don't know if I can install and test it before it cools down again.
I wish my son was a diesel mechanic instead of a motorcycle mechanic and computer technician.

lens12 · Feb 3, 2008

I'd take to an injection shop that has the proper equipment to have it tested.
I don't consider injection pumps an item a owner should attempt to repair.

tallyho8 · Feb 6, 2008

Just an update to let you know that everything is still the same. I am looking for a repair shop to bring it to within 100 miles. Most of them I called will not work on Yanmars. I am waiting for return calls from a couple of places.

There are a few good places around me that will check and repair injection pumps if I remove it and bring it in but I am afraid that this might not be what is wrong and I am afraid that it will check out good when it is cold even if it is acting up when it warms up.

SailorBob · Feb 6, 2008

tallyho8 said:
Just an update to let you know that everything is still the same. I am looking for a repair shop to bring it to within 100 miles. Most of them I called will not work on Yanmars. I am waiting for return calls from a couple of places.

There are a few good places around me that will check and repair injection pumps if I remove it and bring it in but I am afraid that this might not be what is wrong and I am afraid that it will check out good when it is cold even if it is acting up when it warms up.

I am not exactly where in LA you are at but, there was a Yanmar dealer in Waynesborough, MS. That is about 50 miles NW of Mobile.

jameswms · Feb 6, 2008

Tally I have just ran through your exact problem with my Yanmar 2500,it was the injector pump..I also went through of all the fuel and fuel line changing and new bowls,even put head gasket and had head checked for cracks...and yours is doing exactly what mine did,start fine when cold then when it warms up starts to lose power and dies out..A good diesel Injection Pump can check your pump for you..J&H did mine in Miss. 662-3788715.. about $375.00

tallyho8 · Feb 6, 2008

jameswms said:
Tally I have just ran through your exact problem with my Yanmar 2500,it was the injector pump..I also went through of all the fuel and fuel line changing and new bowls,even put head gasket and had head checked for cracks...and yours is doing exactly what mine did,start fine when cold then when it warms up starts to lose power and dies out..A good diesel Injection Pump can check your pump for you..J&H did mine in Miss. 662-3788715.. about $375.00

Thank You
I had read your threads on Hoye's web site and tried to contact you to see if or how your's was fixed. It might help others if you went back to Hoye's site and posted how you fixed it.

jameswms · Feb 6, 2008

Talley check your govenor after putting my pump back on it was still shutting down so I had the guy from John Deere come by and he said its definatel the govenor, he put a spring and did something inside with pliers and it runs great now..

tallyho8 · Feb 6, 2008

jameswms said:
Talley check your govenor after putting my pump back on it was still shutting down so I had the guy from John Deere come by and he said its definatel the govenor, he put a spring and did something inside with pliers and it runs great now..

Where are you located in Mississippi? I would like to know the name of the Deere dealer who worked on it because my local Deere dealer won't work on Yanmars and I may possibly need some work done.
THANKS!!!!!!!!!!!!!!!!
Dudley