i have a early 80's hydra-mac 14-c it runs great all day but if i let it sit over night it is hard to start like it is starving for fuel & when it starts it will just idle dosen't respond to throttle for about 1 to 3 min. then it runs great? i have changed the fuel filter twice cleaned in line screen at feed pump put new valves in feed pump. please help tom
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I wonder if you can install an electric fuel pump in line to give it some pressure. It sounds like the lift pump is still lazy, even though you replaced parts in it.
You could install a hand primer to confirm this. Start it up and give the bulb a squeeze and see if it responds correctly. If so, sounds like the lift pump is not happy, if it doesn't, it may even be air being drawn in. The time it takes to run right could be it purging air that got in the lines. After it sits, the air pocket may come back.
Just a thought
You could install a hand primer to confirm this. Start it up and give the bulb a squeeze and see if it responds correctly. If so, sounds like the lift pump is not happy, if it doesn't, it may even be air being drawn in. The time it takes to run right could be it purging air that got in the lines. After it sits, the air pocket may come back.
Just a thought
thank you Tazza that was my next move but didn't want to invest in electric fuel pump if i didnt have to. i did put a squeeze bulb in the line i have pumped it before i start it & after i start it when it will just idle dosen't seem to make any differance.
If the hand primer doesn't make any difference it doesn't seem to be the fuel lift pump to the main injector pump. The only thing left really is the pump its self or the injectors. Was te primer bulb nice and firm when you squeezed it?
I assume it runs well after its warmed up?
I wonder if it could be the govenor sticking some how? as it warms up, it allows it to release and function as it should? just a thought though.
the squeeze bulb is firm when not running but not when runnig naturally because fuel is flowing through it. this machine had set for about 6 years when i got it i didn't do any thing to the pump or injectors just put some seafom and fresh fuel in the tank.how would i go about checking the governor for a sticking problem? and yes it runs great once she warms up. and thanks again for your help.
I actually don't know if the govenor is inside the engine or part of the injector pump. Some injector pumos that sit externally to the engine have a govenor built into them. It could be in here.
I'm really not sure where else to look. As it runs well after warming up i'd doubt it was the pump or injectors. If the govenor was sticking i'd have guessed it would give erratic operation while it was warm too, not just when cold. If its internal to the engine, the engine oil would be lubricating it. So if it was sticky and started working, it should be free by the fresh engine oil flowing over it.....
i will let you know if & when i figure it out but i think i am going to continue to presume this air in fuel because it just sounds like it is starving for fuel. and thank you very much for your input.
is it possible for fuel to leak from the injector pump into the crankcase via a seal it seems as though i am gaining some oil on the dip stick.
If it has a lift pump attached to the side of the engine, its totally possible you have a crack in the diphragm and its allowing fuel to pass through and into the engine. It will also allow air to enter.....
If you can by-pass it by hooking a hand primer direct to the injector pump, without going through the lift pump. Run the machine, you may need to keep pumping the hand primer though. When its running smooth, shut it down, leave it over night, squeeze the primer bulb to give fuel pressure and get someone to crank, if it fires up as it should, you know its the lift pump.
this lift pump is attached to the side of the injector pump & has a hand primer on it i have checked it before i tried to start it & is firm when pumping. it seems like just the injection pump is loseing some fuel. it has a push rod from the injection pump to the lift pump & i have replaced the seal that the push rod goes through. thanks
well i have finaly gotten around to putting a temporary fuel tank on, that is above the engine or injector pump started it up and ran for a while to get any air out shut it off next morning same thing not wanting to start . any ideas? also does anyone know how to remove & reinstall the injection pump properly off of this qd40 to make sure it is timed properly? thanking you in advance tom
i put new injectors in yesterday same thing today when i started it. i guess the injection pump is next on my list.
It is possible, there must be an air leak there somewhere. Injectors shouldn't allow air to get in the system. There is the nozzle and back at the pump, there are one way valves so air shouldn't be able to get in there..... Is there any sort of bleed screw on the pump for priming? I know Kubota engines have them, you turn the tap out then pump the primer, close and your primed. If the seals were bad it could pull air in and cause your problems.
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Got to be air getting in some place.
You could not find any leaks when the tank was above the engine.
You should send a oil sample in for testing and see if it has a high % of fuel contamination in the oil.
Any way you can put say 5 psi in the tank and let it sit to see if fuel level drops?
It could still be a seal in the injection pump , but its a shame to rebuild the whole thing if it runs fine. Sadly my experience with visiting a pump shop generally resulds in a complete rebuild.
Ken
hi tazza i went with the injectors first because they were cheaper than the pump i know the injectors don't hold much fuel but thought if all were leaking it might take the pump a min. or so to fill them. one way valves you mentioned seemed ok. this pump has a bleed screw & primer pump i have bleed it good & new primer pump assembley. thanks for input tom p.s. pump is in shop will let you know what happens.
no leaks that i could see. preliminary inspection on pump found badly worn delivery valves. maybe 600 to 700 dollars i didn't like that at all gave him $66.00 for his time going elseware.i talked to a gentleman today he said i should have advanced the pump about 2 deg. it might have helped. taking pump to him next week said he would only replace what it needs.
*crosses fingers* hopefully thats all it is, and can be done nice and cheap.
hi tazza sorry i took so long to get back to you guys been mowing grass & getting the garden ready for planting. good news i got my pump back today & this fine elderly gentelmen only charged me fifty bucks for his time. he said there was nothing wrong with the pump.he seems to think i have some air stuck in it some where.so will be chasing air bubbles again i guess. let you know what happens. thanks for your input you guys have a great fourm. tom
well i finaly got the pump back on & while i was waiting for it i took out the fuel tank gave it a good cleaning.[found a 5/8 craftsman socket in there] preasure tested the fuel line & fuel separator from tank to pump. advanved the timing just a bit got it started let it sit for about 4hr. same thing hard to start. does anyone know if the delivery valves in the injector would have any thing to do with this problem?