land cruiser 1hz engine will not start when warm/hot.

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Timing marks look ok. Does it idle slow? Shouldnt really need any throttle to start easy,just the amount of fuel for an idle should start it.
Using a direct fuel supply is always a good idea for diagnostics.
Are the lead wire seals still attached to the fuel pump screws?
Did the previous owner mention these problems?
 
Yeh it will also start with no gas I think. I will check.
I'm not too sure what you mean by lead wire screws?
And the vehicle has been used by our game scouts on the farm for about 4 years now and has slowly been getting more and more destroyed. They have been hill starting now for about 6 months. So getting exact previous faults etc is hard.
 
Lead (as in sinker lead) seals on wire are used by either Toyota or pump rebuilders so you know if the pump settings have been altered. If they have been removed ,you can bet someone has fiddled with the controls.
Is this in Africa somewhere?
 
Hi, Sorry for the late reply. Yes i am in Zimbabwe, the pump has probably been tampered with several times buy non authorised people. i know that this fault started out of the blue at some point in the past 6 months though.
The truck has been sat for about a week or so and i went to start it today and it would not start. battery was maybe a little low on charge but it turned it over a few times and engine would still not start. after about the third time trying the battery failed and started cranking slower.
i am going to try feeding fuel straight to the IP tomorrow to rules that out.
 
Incase anyone else ever has a similar issue, I did end up taking the pump for a referb a couple of months ago and it turned out it was so warn that sometimes when the diesel was thicker and cold it would pull it through but when warm it would not. As soon as the pump was back in it fired up instantly. Thanks for all your help.
 
Hi - I had the same problem on mine and my mechanic said I have a worn Rotor. Upon changing the Rotor, mine started fine when warm. One thing they did was when it was warm and not starting, they used to pour cold water either on the injection pump or starter and then see if it starts ... but it's a while back so can't remember where they poured cold water...

Hope it helps...
 
Yes, this is the exact same issue I had. If cold water was pored all over the pump it would start. All sorted now though, hope this helps any people with the same issue in the future.
 
If the pump is not sucking in air and is getting a healthy supply of fuel, your timing is good, compression is good, and everything else checks out,

Its possible the pump head is worn out. They usually crank fuel fine when cold. Once hot, the clearances around the plunger increase (from 1/1000000 to 2-3/1000000 very small) and it will not deliver sufficient cranking fuel.

The cold water trick is to see if this is indeed the issue. Cool the head and rotor, voila, cranking fuel returns

A common cure for this is to increase the max fuel screw to band-aid the pump until a full recondition can be performed. Common in the old days for cummins performance pumps to be built with old worn heads with the fuel turned way up.
 
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