Mahindra Losing Power - Continued - Solved

[RedDawg]

I posted a few months ago about a 2012 Mahindra 5010 with 690 hours on it losing power. It starts and idles fine but if you put it under any load, including even running it down the road in 2nd gear with nothing attached, it bogs down like it is not getting fuel. That thread is here.

A synopsis is that at first I thought it was the low pressure fuel pump since it wasn't keeping the fuel bowl full. I replaced that and it didn't fix it. Then I figured out the gasket behind the fuel (Off-On-Air) selector on the fuel filter assembly was bad. It was allowing air into the system when it was only supposed to allow fuel, hence the air getting into the fuel filter bowl. You can't buy just that gasket, I made one which was pretty intricate. That didn't work. So I bought the entire fuel filter assembly (ouch) and that also didn't fix it. As part of my efforts I've had the fuel tank off and washed out, all lines are free, air filter has been replaced, the original fuel pump is back on and fuel flows back in the return line like it's supposed to when the tractor is running. You can see that here. Completely fresh fuel. There is no smoke of any kind. There is no moisture or leaking around any injector lines or connections. It will start, idle and run (while sitting the shop) at PTO speeds all day but run up the RPM's and put it under any load and it bogs down.

Before I take this to the Mahindra dealer for really expensive diagnosis and repair, what am I missing? Where else should I look? Thanks.

 

[Vbull]

Plugged up exhaust system? Back when we were going from leaded gas to unleaded a lot of guys were punching out the fill pipe restrictor and putting leaded gas into their vehicles requiring unleaded. The catalytic converters would plug up and allow the engine to start and idle but you couldn't put a load on it. Those early converters were easy to punch out. A loose something in the exhaust could also be restricting the flow.

 

[RedDawg]

Plugged up exhaust system? Back when we were going from leaded gas to unleaded a lot of guys were punching out the fill pipe restrictor and putting leaded gas into their vehicles requiring unleaded. The catalytic converters would plug up and allow the engine to start and idle but you couldn't put a load on it. Those early converters were easy to punch out. A loose something in the exhaust could also be restricting the flow.

Thanks for the reply, Sorry for the delay - traveling a bunch.

The exhaust seems to be free when it is running. I can even idle it at PTO speeds in the shop with no smoke or hesitation. But once under load - that's a different story. Still seems like it's pulling air from somewhere. And it must be after the filter as that problem was fixed. Still trying to find the leak. Thanks again.

 

[BillC72]

Try removing the fuel line from the tank to the bowl to check for free flow of fuel. My 3616 acted very similar to what you describe, I removed the line and used compressed air to blow back into the tank. There are bugs and bug parts in my tank as well as what looks like flash from the plastic tank. I have to do this a couple times a year, until I can remove the tank for cleaning.

 

[RedDawg]

Try removing the fuel line from the tank to the bowl to check for free flow of fuel. My 3616 acted very similar to what you describe, I removed the line and used compressed air to blow back into the tank. There are bugs and bug parts in my tank as well as what looks like flash from the plastic tank. I have to do this a couple times a year, until I can remove the tank for cleaning.

Thank you but as I stated, "I've had the fuel tank off and washed out, all lines are free" Thanks anyway.

 

[mwayne]

Have you checked the adjustment of the governor assembly?

 

[RedDawg]

Have you checked the adjustment of the governor assembly?

No, I haven't but it's a good suggestion. At this point it is out of my hands. I took the tractor to the shop and hope to hear from them what it is. I'll post an update when I know. Thanks.

 

[RedDawg]

Got the tractor back yesterday. Yes, I ended up taking to the dealer about 25 miles away. For those who said the original Mahindra low pressure electrical lift pump never goes bad - well, it does. And for those who said, "just buy the $15 generic one from that jungle website since the Mahindra pump is $253 (and is out of stock), it will work just fine." No it didn't.

Quick recap, I lost any kind of pulling power a couple of months ago. Couldn't pull an 8' Woods mower through a field without killing the engine. Found two things. First, the gasket behind the fuel selector switch on the fuel filter assembly (Off-On-Air) went bad so it was pulling some air when it was only supposed to be pulling fuel. You can't buy just that gasket - you have to buy the entire filter assembly for $90. So I made a gasket! It works fine. No issues.

And the little lift pump next to it went bad. Tried the cheap generic brand off that jungle website ($15). With the fixed gasket in place, it didn't fix the problem. I ended up having to get the actual Mahindra pump ($253) once it was back in stock.

One question, although I ran it around the shop's yard and then loaded it on a trailer, I haven't really run it much. When I got it home and ran it around a bit I noticed my idle wouldn't go below 1600. I haven't called the shop yet but I will if I have to. I recall the idle being about 800 previously. Can't find a spec on it anywhere as to what the idle is supposed to be. Is there a way to adjust the idle speed?

Thanks for the help. Only had the tractor for a couple of years and still learning about it. Appreciate everyone's help.

 

[Molalla1]

Got the tractor back yesterday. Yes, I ended up taking to the dealer about 25 miles away. For those who said the original Mahindra low pressure electrical lift pump never goes bad - well, it does. And for those who said, "just buy the $15 generic one from that jungle website since the Mahindra pump is $253 (and is out of stock), it will work just fine." No it didn't.

Quick recap, I lost any kind of pulling power a couple of months ago. Couldn't pull an 8' Woods mower through a field without killing the engine. Found two things. First, the gasket behind the fuel selector switch on the fuel filter assembly (Off-On-Air) went bad so it was pulling some air when it was only supposed to be pulling fuel. You can't buy just that gasket - you have to buy the entire filter assembly for $90. So I made a gasket! It works fine. No issues.

And the little lift pump next to it went bad. Tried the cheap generic brand off that jungle website ($15). With the fixed gasket in place, it didn't fix the problem. I ended up having to get the actual Mahindra pump ($253) once it was back in stock.

One question, although I ran it around the shop's yard and then loaded it on a trailer, I haven't really run it much. When I got it home and ran it around a bit I noticed my idle wouldn't go below 1600. I haven't called the shop yet but I will if I have to. I recall the idle being about 800 previously. Can't find a spec on it anywhere as to what the idle is supposed to be. Is there a way to adjust the idle speed?

Thanks for the help. Only had the tractor for a couple of years and still learning about it. Appreciate everyone's help.

Have you checked your throttle stick being loose? I had that happen on one of my JD's . . .

 

[RedDawg]

Have you checked your throttle stick being loose? I had that happen on one of my JD's . . .

Seems tight as always but I appreciate the input.