Mahindra losing power

[RedDawg]

Have a 2012 (no emissions) Mahindra 5010 gear drive tractor with @685 hours on it. Changed the oil, oil filter, fuel filter and air filter about 20 hours ago. Recently, after the tractor has run for about an hour the tractor will generally run fine but I lose power. To climb a hill, I have to down shift which I didn’t have to do before, especially if I have anything on the 3 point hitch. Any load on the tractor like thick weeds while bush hogging or an incline while discing drags the RPM’s down considerably. Once that happens, I can start to smell more diesel but I don’t see any leaks around the engine. You have to move the selector from high PTO idle speed to low idle slowly or the engine will die. However, if it dies, it will start right back up again. If you do decrease RPM’s to low idle without killing it, it will surge and porpoise for a while before smoothing out. The tractor is not running warm, and it is not using additional fuel. There is no smoke coming from the engine. There are no unusual sounds – just a decrease in power after an hour or so.

I think I may change fuel filter and air filter again. I have a few acres to mow with the 8’ Woods mower that hasn’t been cut since May when I did it last so it’s fairly thick. It will be interesting to see if it is normal power for the first hour and then loses power and bogs down.

Any ideas on what’s happening? Open to ideas and suggestions.

 

[Rustyiron]

I think you're right about starting with a fuel issue.
Is there a provision for draining-checking for water (condensation) in the tank?

 

[RedDawg]

I think you're right about starting with a fuel issue.
Is there a provision for draining-checking for water (condensation) in the tank?

Not that I can find. I'm the 2nd owner. Had it for about 150 hours at this point and have the owner's manual. Went through it last night looking for that very thing and didn't find anything on it. It would seem to me that water in the fuel would show itself right after start up and not wait an hour. I have added some Seafoam however for that reason.

Going to talk to my local deal when I pick up a new set of filters.

 

[Molalla1]

Have you checked for blockage from the fuel tank to your fuel filter?

 

[RedDawg]

Have you checked for blockage from the fuel tank to your fuel filter?

Yes, it's fine.

 

[Harry in Ky]

Have you considered that your fuel tank is mounted down low. You're relying on a ten year old electric fuel pump to pull fuel from it then push it up into and through the filter. You don't see a possibility of a problem there? Fuel pumps are inexpensive and easy to find. If it were my project I would go there next and do a little investigating.

 

[Jerry/MT]

Have you considered that your fuel tank is mounted down low. You're relying on a ten year old electric fuel pump to pull fuel from it then push it up into and through the filter. You don't see a possibility of a problem there? Fuel pumps are inexpensive and easy to find. If it were my project I would go there next and do a little investigating.

Put a T in the line at the outlet to the lift pump and measure the fuel pressure there. It should be 4- 6 psig. If you can, measure it when you are under load like hogging or climbing a hill. If it's less than 4 psig, you should consider replacing the lift pump.

 

[Mike1955]

Have a 2012 (no emissions) Mahindra 5010 gear drive tractor with @685 hours on it. Changed the oil, oil filter, fuel filter and air filter about 20 hours ago. Recently, after the tractor has run for about an hour the tractor will generally run fine but I lose power. To climb a hill, I have to down shift which I didn’t have to do before, especially if I have anything on the 3 point hitch. Any load on the tractor like thick weeds while bush hogging or an incline while discing drags the RPM’s down considerably. Once that happens, I can start to smell more diesel but I don’t see any leaks around the engine. You have to move the selector from high PTO idle speed to low idle slowly or the engine will die. However, if it dies, it will start right back up again. If you do decrease RPM’s to low idle without killing it, it will surge and porpoise for a while before smoothing out. The tractor is not running warm, and it is not using additional fuel. There is no smoke coming from the engine. There are no unusual sounds – just a decrease in power after an hour or so.

I think I may change fuel filter and air filter again. I have a few acres to mow with the 8’ Woods mower that hasn’t been cut since May when I did it last so it’s fairly thick. It will be interesting to see if it is normal power for the first hour and then loses power and bogs down.

Any ideas on what’s happening? Open to ideas and suggestions.

Where I would start, since you changed the fuel filters is to simply check and re do all that. Then make sure no air is in there. Since you worked there, it where you will find your problem. No offense mean sir, it just my opinion

 

[Rustyiron]

It's his power loss at/after about an hours use. Strange.
Fuel cap venting?

 

[Mike1955]

It's his power loss at/after about an hours use. Strange.
Fuel cap venting?

Rusty iron bear in mind it was running perfectly until he serviced it. Fuel is what he work on. That what I’m betting is wrong. Sucking air probably