MF engines

[native pepper]

Does anyone have any knowledge or experience with MF/perkins engines, have a MF40 with backhoe on it and having loads of problems with the fuel system. It starts instantly, runs for a few minutes then shuts down but will start again straight away then cut out after a couple of minutes.

Have gone through the entire fuel system new filters, bled it many times and it still does it. Today went over it again and thought had fixed it, but after about 10 minutes it slowed and stopped. Very frustrating and no diesel mechanics within a couple of hundred klms, any ideas would be greatly appreciated.

[T1 Terry]

Does anyone have any knowledge or experience with MF/perkins engines, have a MF40 with backhoe on it and having loads of problems with the fuel system. It starts instantly, runs for a few minutes then shuts down but will start again straight away then cut out after a couple of minutes.

Have gone through the entire fuel system new filters, bled it many times and it still does it. Today went over it again and thought had fixed it, but after about 10 minutes it slowed and stopped. Very frustrating and no diesel mechanics within a couple of hundred klms, any ideas would be greatly appreciated.

Do you have a 12v fuel pump you can connect to the fuel feed at the mechanical pump?
First test is to connect the 12v pump input side to the feed from the tank and run it into a large container to check flow over time, the 10 mins max run time you have achieved so far. This will rule out a partial blockage or floating blockage on the tank supply side of the fuel system. The other possible problem is a blocked breather to the fuel tank and a vacuum is forming in the fuel tank.

If that checks out ok, connect the pump output to the lift pump input and bleed the system, then start the engine and see how long it runs. This will test the lift pump.

If the engine still dies, the problem is in the fuel feed between the lift pump and the injector pump, a blocked gauze screen or bronze filter block .... does the fuel flow freely out the return to the tank?

T1 Terry

[BruceS]

NP I think that motor is a 3cyl from memory?
The fuel system on those HATE bio fuel & I'm guessing don't like fish'n'chip oil either but have no idea on that.
On many of the banjo fittings on the fuel pipes there are very fine filters inserted. I'd be checking everyone of those for starters.
The ones used as stationary installs like generators & irrigation pumps have a button to over ride the cut out solenoid until oil pressure goes high enough. I doubt yours has that tho.

[native pepper]

Thanks Bruce, Terry, have 2x12v pumps on the fuel system, one before the lift pump and one before the filters, also have an inline filter before the lift pump. Yes a Perkins, an AD3.152 and Direct injection. It's been running on diesel for the last year or two as it use very little fuel, will have a look at the banjo connections when get home tomorrow to see if there's any mesh filters in them. Was talking to a bloke this arvo about it during a break, who has a couple of old MF and at least one perkins, he's into steam and old engines and runs all his old diesel engines on veggie oil and one real old single cylinder banger on sump oil. He mentioned there's a rubber seal somewhere that can harden up and leak air without there being a fuel leak. Problem is it was so noisy and he was really out of it so didn't quite catch where in the fuel system it was and he'd left before we finished. Know where he lives so will drop in tomorrow morning on the way home and see if he's still alive and can tell me more, staying with friends tonight rather than drive home after playing.

Fuel flows freely from the injector bleed valve and from filters and injectors, as well as from the return lines on each injector which feeds back into the second filter. crack the injectors and fuel flows from them when turning over, so it's frustrating and will probably have to pull the entire fuel system apart and go through it. Will most likely turn out to be a very simple fix, as it happened whilst pushing loads of rocks and soil. Just died on me so changed and inline filter and started it, then it stopped and took a lot of starts to get it back the workshop.

[supersparky]

NP, I reckon there is another one of those gauze thingos that Bruce mentioned, up in the inside of the fuel tank. Only way to access it from memory, is to to drop the fuel tap arrangement with the strainer bowl out of the bottom of the tank. I'm pretty sure the 3cyl Perkins one still had that.

[Keith Morris]

"tanks" here---
I know it is a simple thing to overlook but is the fuel tank cap vent working or is that blocked and causing a vacuum.
Keith.
This happened to me once a long time ago and after all of the testing done it was the fuel cap that was the cause.
Perhaps with the tech advancement the fuel cap does not need to vent. Now this is past my worry stage and modern technology may have eliminated the need.
Keith.

[T1 Terry]

Thanks Bruce, Terry, have 2x12v pumps on the fuel system, one before the lift pump and one before the filters, also have an inline filter before the lift pump. Yes a Perkins, an AD3.152 and Direct injection. It's been running on diesel for the last year or two as it use very little fuel, will have a look at the banjo connections when get home tomorrow to see if there's any mesh filters in them. Was talking to a bloke this arvo about it during a break, who has a couple of old MF and at least one perkins, he's into steam and old engines and runs all his old diesel engines on veggie oil and one real old single cylinder banger on sump oil. He mentioned there's a rubber seal somewhere that can harden up and leak air without there being a fuel leak. Problem is it was so noisy and he was really out of it so didn't quite catch where in the fuel system it was and he'd left before we finished. Know where he lives so will drop in tomorrow morning on the way home and see if he's still alive and can tell me more, staying with friends tonight rather than drive home after playing.

Fuel flows freely from the injector bleed valve and from filters and injectors, as well as from the return lines on each injector which feeds back into the second filter. crack the injectors and fuel flows from them when turning over, so it's frustrating and will probably have to pull the entire fuel system apart and go through it. Will most likely turn out to be a very simple fix, as it happened whilst pushing loads of rocks and soil. Just died on me so changed and inline filter and started it, then it stopped and took a lot of starts to get it back the workshop.

If it hadn't run on pump diesel for quite some time, and then switched back to pump diesel, the low sulphur fuel could be the problem. When low sulphur diesel was first introduced, a lot of the old injector pumps died and had to be rebuilt, the fuel companies covered the costs back then ..... no idea if that deal still exists ....

T1 Terry

[native pepper]

Discovered the problem, the iP has two bleed points, one low one high but the high one is hidden behind the front loader structure and ip controls, the manual doesn't mention the higher one. Found that when downloaded the workshop manual for the Perkins engine in it and how to bleed it properly. Did that and it fired and kept running, been able to get a bit done with it as the council has been dropping off road gravel, soil and rocks from their road works and been updating my tracks and the drive to the neighbours. Now most of my bush tracks are road grade standard and look cool running through the bush. When family come to visit the kids can ride bikes all round the property on roads, which makes them and parents very happy as they spend their days riding and swimming in the dams. Give the horses and grown ups a rest.

[Shirley]

Sounds perfect native pepper, we’ve had our 4 younger g’sons here all day, 9,10, 13, 15 could imagine how they would love your property, actually have them all week Mum & Dad working, it’s great spending time with them.

[supersparky]

Thanks for the follow up on that NP. It's good that it was a simple fix, once you were aware of the bleed point.