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Discussion Starter #1
Hey all, I have been wanting to do this project for a couple years and finally got my hands on the stuff to make it happen.

Bought a 1990 npr with 261k miles and removed all the bits I needed. Right now I'm focusing on picking apart the wiring and cleaning up all the gooey parts.
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Will be using the jr403e and plan on keeping the exhaust brake.
I live in the desert where it gets nice and toasty so eventually I'll need to get the air conditioning operational.
Hopefully I'll be able to drive the truck around with the diesel in it within 6 months :)
 

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That'll be nice. Plan on using the largest transmission cooler you can fit, and you should be fine. Heat kills!
 

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Discussion Starter #3
I have some updates but it has links. Not enought posts yet for some reason to let anyone see my links.. will post soon
 

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Discussion Starter #4
For now I'm just going to hook up the stock isuzu radiator with the trans cooler in it, with the f100 it shouldn't get too hot. In the future though I will add an additional cooler.


Ok so lately I've been doing research on how to mount the motor in the frame. Checked out some factory articles on welding truck frames and been looking at other peoples mounts. Also checked out some welding forums and textbooks on proper technique. And info on the importance of driveline angles.

Here are some links to stuff I thought was helpful

https://www.millerwelds.com/resources/article-library/stuck-on-stick-easy-answers-to-not-so-simple-questions-about-common-electrodes

https://www.aev-conversions.com/education/60

http://trailer-bodybuilders.com/distributors-upfitters/tips-truck-frames

http://www.4xshaft.com/driveline101.html

I put a 50 amp circuit in so I can use my ac stick welder at my house, and I have been practicing with old electrodes on a bike stand I made out of a bedframe, just running some beads up the side to get back up to speed with it. Those cheap auto darkening helmets from the hazard fraud work pretty nicely!

Heres a link to my youtube channel, will be posting updates on the build. So far It's mostly me talking and not doing anything interesting but before too long the truck should have a sweet diesel cradled in the front part, so that will be cool to see.

https://www.youtube.com/channel/UCgzGBLm9bYFEFWi7_EzRB_g?view_as=subscriber

There's another video in between 2 and 3 but youtube says it's a duplicate and wont let me post it... It isn't but it might as well be because its just more talking :tongue:
 

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I know it's just tack welded in the video, but how are you strengthening the engine mount to the frame? It looks like what you have there should be sitting on top of a frame rail and you're welding the edge of that to the inside of your frame rail. But I may not be seeing it right. Just trying to be an extra set of eyes on it for you to make sure you're thinking it all through. Gonna be a fun truck!
 

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Discussion Starter #7
I know it's just tack welded in the video, but how are you strengthening the engine mount to the frame? It looks like what you have there should be sitting on top of a frame rail and you're welding the edge of that to the inside of your frame rail. But I may not be seeing it right. Just trying to be an extra set of eyes on it for you to make sure you're thinking it all through. Gonna be a fun truck!
The crossmember was originally bolted to the lower flange of the Isuzu Npr frame. I sliced an inch or so off each end so it fits to weld inside the frame rails because that is only spot the motor fits. The ends of it have the cross section of an upside down bell, it isn't just a flat edge being welded. I probably will end up adding some gussets though. More updates will come!
 

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Discussion Starter #8
Redid the crossmembers and welded everything permanently! Progress..


Should have the motor bolted in for the last time pretty soon..
 
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I live in south Carolina. The landscapers are always overloading their trucks and pushing them to the limit on the freeway.

I don't think your f100 will be an issue compared to the cab over box truck or ramp bed trucks.

And our temps from July to Aug even Sept are regularly 90+
 

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Discussion Starter #11
Yes, I just haven't been making videos. I spend all of my free time working on it!

Motor and trans are in, radiator mounted, hydroboost+master cylinder from a ford van are mounted with the brake pedal relocator from industrial chassis. Fuel drum from the isuzu is mounted in the bed since the stock ford tank is galvanized. Water separator and lines are plumbed. I have one trans line hooked up, used the stock hoses and fittings with new flared hard line. The other side though wants an adapter that i cant seem to find. 16mm x 1.5 male flare to 14mm x 1.5 male straight thread. I need it to connect the trans to the rubber hose on the drivers side port.. probably will end up using AN or just a barb deal. Shifter is mounted. This weekend I will be mounting the throttle pedal.

List of stuff that's left:

PS pump rebuild kit (seals are crusty)
exhaust - will exit diagonally down over the frame rail , through the inner fender, under the rocker, exit before rear wheel
intake - I have barely any clearance between the turbo inlet and firewell... Hopefully an angled silicone pipe will work. I mounted the engine as far back as I could and was planning on modifying the stock intake to fit but a silicone piece will be much easier if one will fit.
plumb hydroboost lines / brake lines + order deluxe disc brake kit + order proportioning valve
ELECTRICAL - shouldn't be too problematic. The ford has had a few people go through and "fix" things over the years so it needs to be cleaned up
Driveshaft

And miscellaneous brackets/mounting of other stuff - throttle cable, fuel pump on/off / cold start? solenoids, power steering reservoir, air filter... I want to be driving it by summer
 

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Discussion Starter #14
Yessir his rig is sweet! I wish he had more videos. My truck is just going to have the stock config of the motor exactly as it was in the isuzu for now. Probably wont be too speedy. It should be able to stop really well though

And thanks Steve, that might solve my problem
 

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Discussion Starter #17
Yes it is. It has a throttle position sensor and two switches. One for no throttle and one for what seems to be >1/2 throttle. Easier for me to mount that than mount the sensors another way. Trans needs the inputs.
 

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Discussion Starter #18 (Edited)
I started it today! Cranked it for 30 secs to get oil circulating, then disconnected the shutoff cable and it started instantly

I should get the drive shaft back from the shop this week

Picked through the cab wiring this weekend and just have to hook up a few things for the tcu, ignition, and shutoff solenoid. Not going to worry about the exhaust brake yet. Got rid of the glow plug timer as well, not sure if I'm going to add a manual push button for it or not.

Need to mount the air filter and finish the exhaust. Then body work and I'll make a good video showing it off when its all done!

One more thing - gotta install the disc kit i ordered from speedway and plumb that to the new proportioning valve and the master cylinder which came with the hydroboost.
 

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Discussion Starter #19 (Edited)
My neighbor filmed the first start

I hooked up the pump shutoff actuator thanks to the wiring diagram posted by astr, using one of the relays that came in the Isuzu's fuse panel.

Last thing I need to hook up on the trans is "vss2" which is the speed sensor that was a reed switch in the Isuzu's odometer. I bought "New Transmission Output Vehicle Speed Sensor For 2003 02 2001 Isuzu Rodeo Sport" a few months ago on ebay and it gives the same signal as the reed switch, something like four pulses per revolution.

*In the video, the gross metallic noise is a loose exhaust clamp on the down pipe rattling around
 

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Discussion Starter #20 (Edited)
Registration became active last week so I took it for a test drive. Ran great! Shifted in to overdrive at 60mph and crusies at 70 no problem. Made it about 18 miles when the driveshaft let go.
Not sure if it was a bad rear u joint or the thing was too short.

Need a new driveshaft, tailpipe, and yokes. I'm hoping the transmission is still healthy.



*My engineer buddy and the driveline guys gave me their input

Engineer says it was too much torque and it twisted near the yoke, causing it to slip out the front and bang around then break off.

Driveline specialist says the small diameter, thin wall thickness, and length made its critical speed way too low, leading to the previously described situation.

Possible bad rear u joint was caused by my ignorance in tightening the u bolts way too much.. the bearings might've been unhappy

Whatever it was, it now has a 3.5" shaft with a 1350 joint at the rear and 1410 up front. Its 64 5/8" from the front of the flange at the transmission to the rear u joint cap center. Guy said its critical speed is 6000 rpm. I won't be going 143mph so it should be ok.
 

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