Thread: Isuzu `85 110 - Hard starting

G'day Atlantean,
Welcome to the AULRO forum and hopefully I can steer you in the right direction. From what you have said the problem is only starting the engine, and it runs OK once started without any smoke and that is remarkable fuel consumption you have, (normally you would expect around 10L min per 100K). Obviously its not starving for fuel or sucking air or you would find it surging and hesitating in the higher revs range. If as you say the electric fuel stop is working OK I would suggest looking at the fuel lift pump. It's on the side of the injector pump and probably needs replacing. This could explain why it is hard to start but once running it is OK. If it is running fine once started it is unlikely to be injectors or fuel injector pump although the injectors could probably do with a service and adjustment if they have never been done. I had an engine that had done a lot more k's than yours and it still started fine even though the compression was low, if you want to check compression you can get a kits that fit in the glow plug hole instead of removing injectors. 440psi is what you are looking for.
With the LT95, it's most likely your transfer case intermediate shaft needs replacing. Jumping out of gear is indicative of wear on the gear engaging dogs caused by wear in the thrust washers that separate the gears allowing them to move on the shaft (that's presuming you have a standard intermediate shaft setup). Usually by the time you find there's a problem the gears and shaft are all damaged. With those K's I would say it's time you recoed the intermediate shaft or replaced it with a TRB (tapered roller bearing intermediate shaft setup). The good news is it can be done without removing the box from the vehicle.

if you're in brisbane you're welcome out my way and I'll throw the gauges over it for you.

Thanks for your reply - I`ve now read the section on Isuzu parts & will get one of the recommended lift pumps & try the substitution test ( I should have had one spare anyway ) Didn`t give the lift pump much thought this time as I did replace it about 60k ago & the symtoms then were a general starvation of fuel while running.
Regarding the LT95 - I had already taken out the intermediate shaft /bearings/spacers/gears - & yes the shaft is badly worn, as is the main gear ( unevenly worn on running surface ) I`ll read up a bit more on the tapered replacement. Who is the best supplier for either option .
thanks Bruce

Originally Posted by Atlantean

Thanks for your reply - I`ve now read the section on Isuzu parts & will get one of the recommended lift pumps & try the substitution test ( I should have had one spare anyway ) Didn`t give the lift pump much thought this time as I did replace it about 60k ago & the symtoms then were a general starvation of fuel while running.
Regarding the LT95 - I had already taken out the intermediate shaft /bearings/spacers/gears - & yes the shaft is badly worn, as is the main gear ( unevenly worn on running surface ) I`ll read up a bit more on the tapered replacement. Who is the best supplier for either option .
thanks Bruce

G'day Bruce,
Which part of the lift pump did you replace earlier. The hand pump bit or the whole assembly that the hand primer pump screws into - this is the pump I was referring to. It is bolted onto the side of the injector pump, Isuzu part number 8941327070. It is a piston pump driven by a small roller off the injector pump camshaft. This supplies fuel to the injector pump and if worn it probably is not supplying sufficient for start up. This is available through Isuzu truck dealers and is usually cheaper there than through LR dealers. You can do a test to see if this is the problem by getting someone to work the hand primer pump while you attempt to start it - get the fuel pressure up before you hit the key and if it starts there is the problem. If it doesn't make any difference the problem is somewhere else in the fuel system. There is a non return valve in the pump supply line that could be allowing the fuel to drain back when it is stopped that could be playing up.
With the intermediate shaft I have a list of part numbers for the bearings, trust washers, shims etc. needed to set it up. Also the hi range gear part number - PM me if you need them. Suppliers like BMI (Sydney) All 4X4 Kotara (Sydney) BMI (Melbourne), MR automotive (Qld) would be able to help with the parts for the standard intermediate shaft. Which one to use depends on where you live and how urgent you need the bits.

IittiMy 2 cents,

It took me 2 weeks of fuel starvation and priming issues and playing around with lift pumps/replacing fuel lines/ swearing etc. All on the side of the road in the middle of nowhere all to find a short piece of grass root (how???) was stuck in the corner at the top of the pickup pipe and small paint flakes from inside the gerry cans and general fluff and crap had slowly built a beaver dam up behind the piece of grass.....

I know I should have checked that first but for me hindsight is always 20/20.

Anyway this could help.

Cheers
Brian