Diesel Engine hard to start

bowman316 · May 3, 2016

I have a Ford 675e Backhoe with Diesel engine. This thing runs great when we can get it to start, but getting it started can be hard. And
the weather is not an issue, its 70 degrees out. Usually we have to shoot starting fluid into it to get it to start up. Is there air in the
fuel system? How do I bleed air out of the fuel system?

paul · May 3, 2016

What shape is the battery and starter in? I replaced those on a tractor, it didn't seem slow cranking, but with new it cranked much faster, made a world of difference. Fires right up, where as it was always slow to start the first time of the day.

Otherwise, yea, fuel/compression systems, getting old and tired.....

Paul

bowman316 · May 3, 2016

It has 2 brand new batteries on it. If it was low compression, why would it run so good?

mmfan55 · May 3, 2016

Compression can be low on cold engine and improve when it warms up. Can also be a fuel pump a bit weak.

RodinNS · May 3, 2016

It may have an air leak. I'm not sure what fuel system is on that exactly... I would assume it has an electric lift pump? I'd want to verify that it's delivering fuel to the injection pump. There may be a bleeder valve on the side of the pump body. A pic would help a lot....

Rod

wisbaker · May 3, 2016

Could also be folks have been using either on it so long some things are messed up and it won't start without it. When diesels are abused or get old they start losing compression and may become hard to start, use of either can cause additional damage that may worsen the problem. Loss of compression could be from worn piston rings, damaged cylinder walls improper valve clearance, burnt or damaged valves or recession of valve seats. Head gaskets can also cause problems but in my limited experience head gasket problems are less likely to go away on a warm engine unless the thermal expansion of the head is greater than the studs so it's a bit tighter when it's warm (common in engines with aluminium heads).

rrlund · May 3, 2016

Like Rod said,check the lift pump if it has one. I've had two different tractors that the lift pump went bad on and they wouldn't start hot or cold worth a darned.

bowman316 · May 3, 2016

I know this has an electric fuel pump. It don't think it has a lift pump, the non-emissionized version has a lift pump up front, that has a handle you can manually pump. I wish the emmisionized version had that too. But It's just got a small electric pump above the fuel filter, going to the injectors. I loosed the fuel line going from the pump to the injectors, and it had fuel leaking out.

Something weird thou is that when you leave the key in the on position, the fuel pump wont be pumping, unless you turn the motor over for a second, then return the key to the on position. the first time you do it, the pump is not on.

guido · May 3, 2016

Hello bowman316,

I think you found the problem and did not see it. Check to see if the pump is getting power. Sounds like a bad ignition switch. You can hot wire the pump to prove that, if you think you can do it safely,

Guido.

RodinNS · May 3, 2016

I would say the pump is the problem.... It should run continuously. Best I recall those are full flow pumps and are not regulated. What I'd
probably do is remove the supply line from the top rear of the injection pump and turn the key on. Catch the flow in a dish and see if it's
making good steady flow. If not.... check the supply lines to the lift pump or the operation of the lift pump if it's not running...

Rod

Dune Country · May 3, 2016

you may have what I fondly call an "either dog", usually after a diesel has been started with either a few times that's the only way to start them.

flying belgian · May 3, 2016

I'm going to jump on board with the worn out engine people. Low compression.

markct · May 3, 2016

Compression makes heat which is what ignites the diesel fuel when sprayed in. Obviously with a running engine you have more heat, and also more compression since it is turning much faster than it is when cranking so once started it will run fine

4520BW · May 3, 2016

Does it have alot of blow by? If not I would say compression is OK. I would beleive if pump was bad it would be low on power once it's working. If it were mine I would start at the injectors. My old 4230 Deere would not start without either but had plenty of power so I poped the injectors they dumped not sprayed so I bought new ones and now start all winter long with not either.

Kent Petersen · May 3, 2016

That is pure B S

RBoots · May 3, 2016

I rebuilt a Perkins 3A 152 that was addicted to ether. Start very hard, lots of ether to start, ran real well though. When I took it apart, EVERY ring on all 3 pistons was in 1/8" pieces in each of the ring lands.

Ross

tractorguy2 · May 3, 2016

I have a 1966 farmall 706 with the german diesel. Back about 2000 or 2001 got so it would not start without starting fluid and sometimes jumper cables too. I could use it for hours. Shut it off for three minutes and not start without fluid. I bought a rebuilt injector pump and the problem went away. Tractor has 5000 hrs does not smoke or use oil.

MARK ROBKE · May 3, 2016

Well since no one else has mentioned it,my first hunch is a faulty check valve that is supposed to keep fuel from running back to the fuel tank.I am more familiar with trucks,but that was a #1 cause for hard restart.I would suspect in your case that it is in the injection pump.I would crack an injector line,when it won't start,and check for fuel.And then go backwards from there,looking for fuel.Mark

Diesel Engine hard to start

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