lj78 non consistent starting issue

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Postoy

Postoy

10 Year
Joined
Sep 25, 2012
Threads
29
Messages
345
Location
Chilliwack BC Canada
Ok I have a bit of a starting gremlin with my 1990 lj78 (2lte). In the morning my truck starts and runs fine. I drive to work, I am here 8-10 hours. When I go to leave the damn thing takes about 6 minutes and about 50-60 cranks to get it started. Weird right?

Little bit of back ground info.
My truck came with a aftermarket "Wilson" switch installed by the PO
This problem stemmed after I replaced my injectors 2 weeks ago, I grounded out my glow rail when I put everything back together and fried my fusible link wire that goes to the battery... Not knowing what this wire was I "upgraded" it with a larger wire and tried starting it again. Well all this did was fry the wires going into the glow plug relay (the round one behind my battery). So I have since replaced that plug, changed the fusible link back to the way it was and sorted out my grounding issue.

Do you think I have done damage to my stock relay? I am considering picking up a 100 amp relay from princess auto and bypassing my stock system all together. I'd switch the glow plugs on manually with a momentary switch. Thoughts? Thank you in advance! -M
 
Also, I have pulled and tested all my glow plugs. With 12V they all glow... seem a bit slow so I ohm tested them. All about 1.3-1.5 OHMS. I have replacements on order.
 
Postoy said:
Ill post in the diesel form as well

GTSSportCoupe - Good call.... Now... wonder where I will find one of those :( Time to start searching...
Click to expand...

There is a JDM outfit in Armstrong BC that has a couple parts Prados/Surfs. I bet they'd ship you the relay for a pretty good price. I've dealt with them before and they are really good.

  • J Cruisers JDM Vehicles & Parts
  • 135 Pleasant Valley Cross Road Armstrong, British Columbia V0E1B2
  • Tel 250-546-9805
  • Email mail@jdmparts.ca
Sorry, I don't know what the relay looks like off the top of my head. There are two with the stock system though, one for after glow I think. Could just get both if you are in doubt.
 
Another thought... could this be a fueling issue? Once again... truck wouldn't start so I tested the leads going to the glow rail. Would get 12v till first click. Then 5-6v for the second click.

Thinking maybe there is a air leak that is pulling the fuel back into the tank when it site. I park the truck backed up a hill aT home but on flat ground at work... I dunno just thinking out loud.
 
Postoy said:
Another thought... could this be a fueling issue? Once again... truck wouldn't start so I tested the leads going to the glow rail. Would get 12v till first click. Then 5-6v for the second click.

Thinking maybe there is a air leak that is pulling the fuel back into the tank when it site. I park the truck backed up a hill aT home but on flat ground at work... I dunno just thinking out loud.
Click to expand...

Could very well be. Especially considering you had your injector hard lines off recently. Look for diesel leaks around everything you had apart. Air will get in where diesel gets out.
 
Postoy said:
That's gonna be the problem no leaks that I can find... maybe possible only air is getting in and no diesel getting out?
Click to expand...

The weird thing is, why doesn't it happen in the morning? You'd think it would be worse then after sitting so long. Not sure man. If anything comes to mind I'll let you know. Could try pumping the primer again and see if that helps. I wish you were on the island, I could help troubleshoot it.
 
I would say it Could be your injector pipes and copper washer seals. definitely fuel related.
electrics are simple.
 
Pump your primer before starting, if it stiff after a couple pumps great, if soft and spongy for multiple pumps I would suspect air.
Start from injector piping and work back towards the fuel tank checking all connections.

Try a clear fuel hose between the fuel filter and IP to look for fuel or air. Great troubleshooting aid, yes you can leave the clear hose on and drive for years.
 
Ok so it's a fuel issue. Once again started up right away this morning. Went to leave work and no dice. So I primed the system a bunch. Still took a few cranks but started a lot quicker than normal. Also I could hear something making a click sort of sound every time I pumped the primer. Figured that was the sounds of air moving around?
 
if you did the injectors, I am assuming you disconnected the fuel hoses too. they would be brittle and old could leak air. better change them. clear hose is good idea to eliminate the primer pump.
 
Oh the primer pump could be faulty... never really thought of that. Is there anything in the injection pump that could cause a diagnosis like this?

I'll try and find some clear line and swap it
 
Well... I changed all the fuel lines and the copper washers on the hard line going to the injection pump (it was damp around it before) bleed the system and drove it around no problem. Went to start it up this morning to go to work.... didn't start... I'm just about ready to give up on this thing.
 
How is your primer?
If the primer is still soft then your problem is towards the tank. Try the clear hose.
You know the thing runs when it gets fuel, just make sure it gets fuel without air.

For s***s and giggles disconnect the fuel line from the primer and using a funnel or similar device feed fuel directly to the IP from a position above using gravity, again if she runs your problem is air.......... or a dirty filter which I doubt.
 
I'm not sure what the primer should feel like but yes it's pretty much always easy to pump. I have clear urethane line but I'm not sure that is OK to use on the truck as its only rated to 60 psi. I know there isn't much pressure to the IP but after isn't there a lot?
 
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