Engine starting problem

No haven't looked at the lift pump - no reason to as it wasn't a problem before but a good tip -thanks.

I used to use about 1/3 throttle before but now I've tried everything between none and full.

Thanks everyone
 
Try spinning it over with the decompressors on for 15 secs on full throttle. Leave for 2 mins. Then start on 1/3rd to 1/2 throttle. Tip I picked up from a Yanmar forum and seems to work on my 3gm when its difficult to start.
 
As you appear to have had a job getting the fuel fed to the engine I wonder if there is a vacuum being created,possibly a blocked vent pipe into the fuel tank,or debris at the outlet from the tank.Did you use PTFE tape on any of the connections- this is a no-no apparently,and can temporarily cause a restriction to the flow of fuel. In any event I think I'd suspect the fuel sources first.
 
In your opening post you say you replaced the cylinder head. Did you mean you replaced it with a refurbished one with valves ground in? Sorry if the question is a bit basic; but the symptoms you describe of difficulty in cold starting but easy when warm is a symptom of valves not bedding in until hot when then metal expands. I appreciate you have said that it is difficult to turn over by hand which suggests good compression; but its worth checking your valves if no other solution has been found. /forums/images/graemlins/cool.gif
 
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This does sound like a fuel problem. A leak can be too small to let fuel out or cause problems in normal running, but still cause problems when the engine's been standing 'cos it's let a bit of air in.

Unfortunately I don't know of any easy way to find those kinds of leaks. Dusting all the joints with talc may show an otherwise invisible weapage of fuel. If you can figure out a way of putting the fuel system under positive pressure, that could help by encouraging diesel leakage that the talc will highlight.

Good luck!

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I agree with you.

But a leak letting air in frequently (nay usually) won't show any fuel seepage.

I'd lay £1:1p that there is a high-level leak into the fuel-line, probably where the fuel pipe comes out of the tank.
 
Agree it must be air as everything else looks to be sound. I had a similar problem last year. I never found the leak but liberally applied red stag to all joints and it was fixed. Took some 12 hours work to eliminate everything else first though. /forums/images/graemlins/confused.gif
 
I'm not suggesting that this is the cause of your problem..... just seems strange, unless I've been missing something
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This is exactly what he should be doing on an engine which is lazy starting as otherwise he risks getting water backflowing into the engine with prolonged use of the starter.
 
YOur problem sounds to me like air leaks. Did you change filter elements when you were working on the engine over winter. Is it possible you twisted a ring in a prefilter??? is there a lose connection. Is your prefilter between the lift pump and tank.?

If the prefilter is above fuel level then it can allow air in may not leak fuel and due to design you may not see the air in the filter cartridge.
 
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