Hard to restart once engine is at runing temprature (Diesel)

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Lebmob
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Hard to restart once engine is at runing temprature (Diesel)

Post by Lebmob »

Hey team, can anyone tell me why would that be???

Car start fine with a cold engine, but once it drives for a bit and gets up to normal temprature, and then if I turn it off I'd have to wait for a good 20 + minute if not more before if would start again....

Now during this time, if I'd tried to start it, it would turn over ok but no start, it can be pushed started, starter motor rebuilt>>>>
battery and battery cables ok.

Any thoughts??
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DaveM
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by DaveM »

What motor/vehicle?
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Jerry
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Jerry »

FJ40 2b Diesel I think......??
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valiant87
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by valiant87 »

Had that in my V8 Fairmont all it was was a loose earth wire plus a bit of corrosion on the battery terminals tightened cleaned fixed :D
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mercutio
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by mercutio »

check compression
my 4wd is not a truck

old mercedes never die but sometimes they do need some love

older cars are good,mercedes are better,older mercedes are the best
Lebmob
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Lebmob »

Hi thanks for the tip, checked mine, all in good order :!: :?:
Cheers

valiant87 wrote:Had that in my V8 Fairmont all it was was a loose earth wire plus a bit of corrosion on the battery terminals tightened cleaned fixed :D
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Nivapulledout
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Nivapulledout »

I am guessing you mean it does not want to turn over when warm?
If this is the case is there anything you have done that could cause the starter motor to be exposed to excess heat? if not the starter could be poked. if you do a voltage check from the pos term on bat to pos term on starter while cranking you should get no more than 0.5 V reading, if more it is bad cable/connection. Do the same from the starter body or Neg term if you have one to the neg of bat while cranking , This test will completely rule out your cables and connections as it is checking the voltage lost between these two points.(do it both when cold and hot and compare the difference.
if these readings are good then check batt volts while cranking and they should not drop below 9.5v. if they do then batt is possibly fooked and need to take to sparky and get tested.
if both these tests check ok then I would say you have a bad starter.
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Nivapulledout
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Nivapulledout »

just read your message again and you said it cranks ok... mmm try checking/swapping out your fuel cut off solenoid as it could be jamming when warm.
If it can be push started then I still think it is your starter not turning fast enough. but hard to tell without seeing/hearing the fault.
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Steve_t647
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Steve_t647 »

sounds like a fuel issue, the engine is still hot so no need to glow and it cranks fine... What else is there in a old diesel?

You may want to bleed the injectors and see if any air comes through, with heat air will expand. Fuel is where I would look, wear gloves diesel is not nice for the skin.

Only other thing would be the pump fuel solenoid sticking shut and that bit is black magic!
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Nivapulledout
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Nivapulledout »

diesel is not that bad for the skin in small doses, I have been exposed to it on my hands and forearms just about everyday for the last 15 years.
However a small amount people do get irritated by it and can develop a skin disorder called dermatitis however this is more prevelant if skin is exposed to mineral oil(hydraulic oil is super bad), this is condition is nasty and if your body even smells diesel or oil you will come up in a rash.
So wear gloves if you are not sure, but if diesel gets in/under the rubber gloves(which almost always happens) then it can irritate the skin worse than if it gets on your hand and you wipe it off with a rag.
just my 2 cents :lol: :lol: was bored :D
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Nivapulledout
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Nivapulledout »

just had another thought on this......

Does your engine black smoke/white smoke?
Is it down on power when it is running?

Do a check on your fuel supply and return lines. check for tightness on all clamps and also how hot the fuel lines are getting.
Where does your fuel return line from the INJ pump go?? is it looped back to the pump supply or do you have a return line all the way to the tank?
Check this fuel return is not blocked.
Check temps if you can on the fuel supply to the pump and also the fuel tank itself ( these should be checked when engine is hot and will not start)

Diesel loses its clorific value the hotter it gets(less power for same amount of fuel) and this will start at anything over 45 deg, ( not to mention it starts producing flamable fumes after that) it is ok for the fuel return to be hotter than this but the tank and the fuel supply should be below this temp.

another thing could be a worn injector pump and with the warm low viscosity diesel it has to much leak back on the pump pistons. but to do this it would need to be really worn. you could check this by removing an injector/using spare injector and using an old injector line(bend it so you can spray into a ice cream container away from hot exhaust)checking the spray pattern on each outlet from the pump. but really should check with your injectors so you are checking all components.

but once again engine needs to be hot so work fast.
Lebmob
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Lebmob »

Appreciate the advice, I'll check it over again, Thanks

Nivapulledout wrote:just read your message again and you said it cranks ok... mmm try checking/swapping out your fuel cut off solenoid as it could be jamming when warm.
If it can be push started then I still think it is your starter not turning fast enough. but hard to tell without seeing/hearing the fault.
Lebmob
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Lebmob »

Hi. thanks I'll double check!!

Steve_t647 wrote:sounds like a fuel issue, the engine is still hot so no need to glow and it cranks fine... What else is there in a old diesel?

You may want to bleed the injectors and see if any air comes through, with heat air will expand. Fuel is where I would look, wear gloves diesel is not nice for the skin.

Only other thing would be the pump fuel solenoid sticking shut and that bit is black magic!
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kbushnz
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by kbushnz »

Have you been off road and knocked the fuel line closer to a heat source....Vapour lock??

Or as already discussed....Air leak in fuel system...

Cheers
Calvin
Cheers Calvin
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Lebmob
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Re: Hard to restart once engine is at runing temprature (Diesel)

Post by Lebmob »

Hi Calvin, appreciate the tips, will check all over the weekend...
Fingers crossed, I'll find somthin simple :o :oops:

kbushnz wrote:Have you been off road and knocked the fuel line closer to a heat source....Vapour lock??

Or as already discussed....Air leak in fuel system...

Cheers
Calvin
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