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86 Comanche long bed project revival

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Greetings and nice to meet you all,

I was told this was a better forum for MJ content than the last one I was on. Thank you, smokeyyank.

I've recently picked up a build project that seems to have stalled close to the finish line and then sat for 4 or 5 years. The truck is 95% build complete with a few items left to sort. It is powered by an intercooled Cummins 4bt mated to an NV4500 and NP241.  The rear is a Dana 60HD with drums, and the front is a Dana 44 with broken gears. It sits on hummer bead locks and 37's.

I am currently replacing filters and the lift pump with hopes of having it running this week.  I am looking into new rear leaf packs to eliminate the current 4" blocks being used. My hope is to build a king pin Dana 60 to replace the Dana 44.  My goal is to have it sorted and ready to hit the trails this spring. Thanks in advance for the technical support.


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The new lift pump is now installed along with fresh fuel filter and a new oil pressure switch while I had access to it. Charging the battery now, I will bleed the injection during my lunch break tomorrow and see if she will light.



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Drained about 18 gallons of very old diesel out of the fuel tank. I purchased a little 12v diesel "mini" pump for under $25 on Amazon. Is it ok to post links to things like this or is that a discouraged practice on this forum?

I spent about 30 minutes draining the tank, the pump made it a breeze. 



The fuel looked pretty bad.



I added about six gallons of fresh diesel and pumped some more until clean. Connected back up to the new lift pump and it is now running on the tank rather than my hanging fuel pot.

The PO stated that the steering box was faulty and causing issues with the hydro boost and brakes. When my son tried to drive it, the brakes didn't seem to properly release. I suspect the bad steering box was stopping power steering fluid flow and the small return line on the hydro boost was insufficient to let the pressure release.

Being lucky enough to live close by, I will be dropping by Redhead steering gears next week for an 18510 box and adding pre-porting for hydro assist. Not adding hydro in until I get the current system sorted. As I have learned from the wise, too many variable changes makes for muddy waters when trouble shooting. I will get the new box installed and then see how everything is behaving. 

After much consideration, I think building a d60 front is not the wise or economical choice for getting on the road. I think salvaging this Dana 44 is the most cost-effective route for now. I will need to re-clock the inner knuckles and make some geometry adjustments to the pinion angle and how far the axle is pushed forward.  The track bar and steering linkage is super close together. Not a ton of clearance for the pitman arm either.



A new set of gears, better pinion geometry, and maybe a locker and the D44 should last me just fine while I complete other portions of the build.  I can do a D60 build down the road if I really feel it makes sense.

Next engine item I will attend to is topping off coolant and seeing what shape that system is in. I'd also like to start doing some wiring research.  I would like to get all of the engine wiring overhauled in the bay including having all of the stock gauges working. I believe that should be doable with a reasonable amount of effort with the tach being the only one with some hurdles. The good news is it seems all the wiring harness plugs on the firewall are intact.



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  • 2 weeks later...

Picked up the new steering box. The old box came out quickly with minimal fuss.


The reinstall went even quicker.



After bleeding the system I have power steering again. The hydroboost system is still locking up the brakes when applied. I stayed off the brakes and was able to drive a short little circuit around my yard and things seem pretty good. I did more research on the hydroboost and found that the return line from it can cause issues if it doesn't have sufficient ability to return flow. I found that the hydroboost returned to a custom fitting added to the power steering pump.  I decided to try swapping the returns on the hydroboost and the steering box.  This didn't fix anything but made clear that the custom return fitting allows zero flow.  I am going to try to throw in a Y or a T on the stock return line and see if I can get any improvements.  My research indicates that getting a pump with 2 stock returns is the best solution.


Edited by Jeremy
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