Build LJ78 Build

[Gun Runner 5]

Had one of similar color .

 

[GTSSportCoupe]

Had some questions and concerns though…

The truck has been starting pretty rough when cold. Won’t start without pressing the throttle and when it does start it feels like it’s misfiring. I ordered new glow plugs this morning so will try that but I’m wondering if it could be related to the throttle body plate delete or EGR delete. I remember the rough start starting the day after I did that. I’m not going to rule out other issues but it would be pretty coincidental.

Could the lack of butterfly plates in the throttle body be letting too much air in? Or another vacuum leak? I’ve poked around quite a bit and sprayed all over with brake cleaner while running to check for vacuum leaks but it all looks solid.

I do also wonder if the fuel system is losing prime over night? I’ve read that the fuel primer/filter mount can go bad and let air in. Any good way to test that? Kind of an expensive part to buy just on a hunch. Also any good way to test if the injectors are leaking?

It's a constant battle with these. But I can say a daily perfect start with no misfire is totally possible. Here is what I've had to do over the years to fix misstart:

- Fixed compression (my original engine had low compression from water rust damage in one bore, I guess after head had cracked in Japan originally and it sat with water in it).
- Replaced flexible rubber hose and clamp on fuel rail return to IP (if air gets in, it causes misfire).
- Replaced fuel primer with a Chinese made Hilux one from eBay (air can get in around worn out hand pump)
- I always run 'Power service' (Canadian tire) fuel additive. I think that is one of the biggest differences. It keeps injectors clean. I do a lot of short drives and fuel is turned up, so it's a bit rich till boost hits. So might be an issue only for me. When I forget to use it, it takes at least a whole tank to clean my injectors again.
- Replaced injectors with new ones along with new nozzle crush washers etc. The new nozzle washers are very important to keep nozzles from fouling. Only do this as a last resort of course as they're really expensive.
- Replaced IP with a brand new one I lucked upon
- Replaced glow plugs, clean glow rail connections with scotch bright etc.
- Use the right start sequence: Turn key to 'on'. Listen for glow relay to open a few seconds later. Then start. Ignore the stupid glow light, it's timing is too fast.
- I live at sea level which probably helps (lots of air).

Here is how mine starts every day in the morning (cold engine) no matter the weather.



I like your wheeling pictures. I have not read your whole thread, maybe you've done this. But the 'ah-ha' moment in making an LJ78 into a wheeling monster is to install soft radius arm bushings front AND back at the axle end of the arm (same size fits front/back; caster correction ones fix rear caster too). The factory ones are way to stiff. Definitely don't use polyurethane ones!! The soft bushings do wear out every few years, but it's really worth it imho. Second thing is remove both sway bars (or at very least the front). Soft tall springs with longer shocks are good. Anyhow, these trucks become spiders.

One thing to watch for when flexing is the rear steering linkage (behind axle) can catch on the radius arm. Be careful about not forcing your steering if it seems stuck. I think the castor correction bushings make this a problem. The part that catches can be rotated a bit to reduce the chance of this happening.

 

[aidanshmaden]

It's a constant battle with these. But I can say a daily perfect start with no misfire is totally possible. Here is what I've had to do over the years to fix misstart:

- Fixed compression (my original engine had low compression from water rust damage in one bore, I guess after head had cracked in Japan originally and it sat with water in it).
- Replaced flexible rubber hose and clamp on fuel rail return to IP (if air gets in, it causes misfire).
- Replaced fuel primer with a Chinese made Hilux one from eBay (air can get in around worn out hand pump)
- I always run 'Power service' (Canadian tire) fuel additive. I think that is one of the biggest differences. It keeps injectors clean. I do a lot of short drives and fuel is turned up, so it's a bit rich till boost hits. So might be an issue only for me. When I forget to use it, it takes at least a whole tank to clean my injectors again.
- Replaced injectors with new ones along with new nozzle crush washers etc. The new nozzle washers are very important to keep nozzles from fouling. Only do this as a last resort of course as they're really expensive.
- Replaced IP with a brand new one I lucked upon
- Replaced glow plugs, clean glow rail connections with scotch bright etc.
- Use the right start sequence: Turn key to 'on'. Listen for glow relay to open a few seconds later. Then start. Ignore the stupid glow light, it's timing is too fast.
- I live at sea level which probably helps (lots of air).

Here is how mine starts every day in the morning (cold engine) no matter the weather.



I like your wheeling pictures. I have not read your whole thread, maybe you've done this. But the 'ah-ha' moment in making an LJ78 into a wheeling monster is to install soft radius arm bushings front AND back at the axle end of the arm (same size fits front/back; caster correction ones fix rear caster too). The factory ones are way to stiff. Definitely don't use polyurethane ones!! The soft bushings do wear out every few years, but it's really worth it imho. Second thing is remove both sway bars (or at very least the front). Soft tall springs with longer shocks are good. Anyhow, these trucks become spiders.

One thing to watch for when flexing is the rear steering linkage (behind axle) can catch on the radius arm. Be careful about not forcing your steering if it seems stuck. I think the castor correction bushings make this a problem. The part that catches can be rotated a bit to reduce the chance of this happening.

Thanks for the reply! I’ll work through that list and try and sort out the starting issue. I feel like it’s getting air in the lines and I’m pretty sure I have an injector leak on one of the back two injectors/lines.

I have the front and rear sway bars disconnected already which surprisingly hasn’t made it drive too bad on the road. Soft rubber caster correction bushings are definitely on the list. I found a post you made about those a little bit ago. I believe these are the ones, right? Waiting to figure out a way to push them out and back in. I do all my work in the carport behind my apartment so I don’t have anywhere to put a press at the moment haha.

 

[GTSSportCoupe]

Thanks for the reply! I’ll work through that list and try and sort out the starting issue. I feel like it’s getting air in the lines and I’m pretty sure I have an injector leak on one of the back two injectors/lines.

I have the front and rear sway bars disconnected already which surprisingly hasn’t made it drive too bad on the road. Soft rubber caster correction bushings are definitely on the list. I found a post you made about those a little bit ago. I believe these are the ones, right? Waiting to figure out a way to push them out and back in. I do all my work in the carport behind my apartment so I don’t have anywhere to put a press at the moment haha.

No prob. Yeah, try all the simple cheap stuff first.

Yes, those are the bushings I use. I had to change the front ones again recently. I used to use a press at work, but now I bought a cheap one from Princess Auto that did the trick nicely. Ignore the mess in my shop (was getting rid of a bunch of stuff). This is the press, and this is how bad my soft rubber bushings looked after six years or so! I let them go a year or two too long, haha.

More ideally, a person would make a custom radius arm that corrects the caster by design. Then use 80 series oem bushings which are better than LJ78 ones. They have holes that give decent articulation movement.

 

[aidanshmaden]

No prob. Yeah, try all the simple cheap stuff first.

Yes, those are the bushings I use. I had to change the front ones again recently. I used to use a press at work, but now I bought a cheap one from Princess Auto that did the trick nicely. Ignore the mess in my shop (was getting rid of a bunch of stuff). This is the press, and this is how bad my soft rubber bushings looked after six years or so! I let them go a year or two too long, haha.

More ideally, a person would make a custom radius arm that corrects the caster by design. Then use 80 series oem bushings which are better than LJ78 ones. They have holes that give decent articulation movement.

View attachment 4243820

View attachment 4243821

5 or 6 years is still pretty decent! I remember reading a thread about a guy making custom radius arms for the LJ78 but seems like he took some people’s money and never actually made the parts… hopefully someone designs a set and actually delivers them.

PS. Don’t want to sound like a creep but I was driving behind your truck the other day haha. It’s looking good! Theres a good handful of these things around town which is cool. Recently saw another in the same colour as mine even.

 

[GTSSportCoupe]

5 or 6 years is still pretty decent! I remember reading a thread about a guy making custom radius arms for the LJ78 but seems like he took some people’s money and never actually made the parts… hopefully someone designs a set and actually delivers them.

PS. Don’t want to sound like a creep but I was driving behind your truck the other day haha. It’s looking good! Theres a good handful of these things around town which is cool. Recently saw another in the same colour as mine even.

Haha, that's funny. You probably noticed the right side lean. Downside to my tall soft springs! I even swapped them left to right sides and it made no difference. Trucks are 90lb heavier per wheel right side. Enough to lean? I do wonder if a longer panhard would help too.

We used to have a bunch of cruiser owners who met monthly at one of the pubs in Victoria. Maybe should try to revive that sometime as would be neat to meet yourself and some other new faces....

 

[aidanshmaden]

Haha, that's funny. You probably noticed the right side lean. Downside to my tall soft springs! I even swapped them left to right sides and it made no difference. Trucks are 90lb heavier per wheel right side. Enough to lean? I do wonder if a longer panhard would help too.

We used to have a bunch of cruiser owners who met monthly at one of the pubs in Victoria. Maybe should try to revive that sometime as would be neat to meet yourself and some other new faces....

Yep mines got the lean too. That would be sweet!

 

[GTSSportCoupe]

You can borrow the press when you do your bushings if you like...

 

[aidanshmaden]

You can borrow the press when you do your bushings if you like...

Thats very generous! I may take you up on that.

I just went out and had a poke around and may of found the smoking gun to my starting issues. I pumped the fuel primer on the filter cap a few times and had some fuel leak out right from under the pump knob... looks like I'll be ordering a new one!