Isuzu 6bd1 hard start

[Isuzu6bd1]

Have a isuzu 6bd1 in a hitachi ex200.. Hard to start, will start easy on sniff and run all day no problem.. Just starting hot or cold is a problem, not using oil or down on power, fuel lines and banjo filters all are good.. Starter motor may be a lil slow but not bad.. Any idea what to try

 

[alrman]

Welcome to HEF @Isuzu6bd1
There is a flexible coupling that drives the injector pump, it may be begining to fail.
Wouldn't hurt to check compression as well.

 

[Isuzu6bd1]

Welcome to HEF @Isuzu6bd1
There is a flexible coupling that drives the injector pump, it may be begining to fail.
Wouldn't hurt to check compression as well.

Sorry forgot to say compression is good also checked.. Will check the coupling on the pump it does seem like a diesel problem.. thank you

 

[Diesel Dave]

EX200 6BD1T fuel injection timing spec 16 deg BTDC.
.

 

[Cliffy]

Worn injectors with excessive leakoff can cause hard start issues as well. Leakoff volume is to high to reach popoff pressure at low rpms. What was the compression psi? By the spec sheet above should be 441psi.

 

[thepumpguysc]

Doesn’t that mdl pump have a supply pump bolted to the side.?
Try hand pumping it before turning the key.. that’ll tell u if there’s a supply problem..
Good luck..
1 more thing.. I think that mdl has a plastic filter screen in the banjo bolt below the hand primer..(fuel inlet)

 

[Tones]

Doesn’t that mdl pump have a supply pump bolted to the side.?
Try hand pumping it before turning the key.. that’ll tell u if there’s a supply problem..
Good luck..
1 more thing.. I think that mdl has a plastic filter screen in the banjo bolt below the hand primer..(fuel inlet)

They sure do. Also in those pumps there's plastic plungers that get pitted over time and won't pump fuel. They're easy to replace and cheap as chips.

 

[Isuzu6bd1]

Worn injectors with excessive leakoff can cause hard start issues as well. Leakoff volume is to high to reach popoff pressure at low rpms. What was the compression psi? By the spec sheet above should be 441psi.

Ah ok.. I haven't performed the compression test myself was by someone else who said it was in spec..

 

[Isuzu6bd1]

Doesn’t that mdl pump have a supply pump bolted to the side.?
Try hand pumping it before turning the key.. that’ll tell u if there’s a supply problem..
Good luck..
1 more thing.. I think that mdl has a plastic filter screen in the banjo bolt below the hand primer..(fuel inlet)

Yes have tried pumping it up before start made no difference.. Yes all screens and filters have been changed alrite still the same issue thanks

 

[Isuzu6bd1]

They sure do. Also in those pumps there's plastic plungers that get pitted over time and won't pump fuel. They're easy to replace and cheap as chips.

Seems to be pumping lots no problem filling the lines and filter after change one thing I'm wondering about is pump timing maybe

 

[thepumpguysc]

It might be the pumping plungers inthe pump itself.??
Not pumping enough fuel to start the engine..but run fine afterwards..
Do u have any fuel in the oil.??
THATS a clue that the p&b’s are worn..

 

[Isuzu6bd1]

It might be the pumping plungers inthe pump itself.??
Not pumping enough fuel to start the engine..but run fine afterwards..
Do u have any fuel in the oil.??
THATS a clue that the p&b’s are worn..

Ah rite ok.. No fuel in the oil or at least not obvious.. Going to get back to it in afew days and try afew more things

 

[thepumpguysc]

Another thing u can do is:
Remove an injector and hook it back up to the line..OUTSIDE THE ENGINE..& crank the engine..& see if it’s popping open the injector..
DO NOT GET NEAR THE SPRAY..
The spray WILL penetrate your skin and you’ll get blood poisoning..
Good luck

 

[Isuzu6bd1]

Problem sorted..rack on pump seemed to be stuck..screwed off cap and moved manually and starting perfect again..what is the idea of adjustment screw in the end or how should that be adjusted or removed fully

 

[thepumpguysc]

That’s to limit the starting fuel..
So it doesn’t wash down the cylinders with to much fuel..
The adjuster is usually a 4 or 5mm Allen screw..??
If so, u can turn it “IN” a full turn or 2..
To be on the safe side, adjust the screw and put the cap on and give it a test start..
Good luck

 

[Isuzu6bd1]

That’s to limit the starting fuel..
So it doesn’t wash down the cylinders with to much fuel..
The adjuster is usually a 4 or 5mm Allen screw..??
If so, u can turn it “IN” a full turn or 2..
To be on the safe side, adjust the screw and put the cap on and give it a test start..
Good luck

Ah ok.. no just an 11mm bolt with a lock nut.. is there any way to adjust it to spec or just trial and error..barely cranking and it's starting now which is great

 

[thepumpguysc]

The cranking/starting fuel is set with the pump on a test stand using test injectors..
What u can do is: seeing it’s starting NOW.. back the screw OUT a turn at a time until it fails to start..
THEN turn it IN a turn at a time until it starts..and lock it down there..
Be sure to put the cap back on after each turn and test..

 

[Isuzu6bd1]

The cranking/starting fuel is set with the pump on a test stand using test injectors..
What u can do is: seeing it’s starting NOW.. back the screw OUT a turn at a time until it fails to start..
THEN turn it IN a turn at a time until it starts..and lock it down there..
Be sure to put the cap back on after each turn and test..

Perfect wil give that a try thanks