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Discussion Starter · #41 ·
Thanks for the heads up. I wondered about vibrations killing it, didn’t have any first hand experience though.

ive been trying to search for filters but all Amazon searches lead me to those “sediment filters“ aka almost illegal Chinese silencers lol. I will browse summit racing and see if I can find a high micron type of filter.
 

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Discussion Starter · #44 ·
No dice.

Fired up and ran fine today while loading up gear and a mtn bike. As soon as I took off I watched the fuel psi drop. Popped the hood and clear plastic filter was empty. I can see it pulling fuel/air bubbles. Looking more and more like a pick up issue vs the crap fuel. 😐
 

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Is the rubber hose from the tank to the hard line new? The rubber hose gets old and cracks. Another possibility is rust pin holes in the hard life from the fuel tank to the fuel pump.
 

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No dice.

Fired up and ran fine today while loading up gear and a mtn bike. As soon as I took off I watched the fuel psi drop. Popped the hood and clear plastic filter was empty. I can see it pulling fuel/air bubbles. Looking more and more like a pick up issue vs the crap fuel. 😐
if you work on enough crap you get to see a lot of weird thing... like a hose that looks good on the outside and has a tear in the inside acting like a valve.. or a chip of rust floating in the tank that covers the pick up or in the line and it turns closing the line off.. ... easiest diagnoisis is always working backwards... disconnect at the inlet side of the filter.. run a new hose into a couple of gallon tank with new fuel and run for an hour.. if it will.. if it does.. you move back to where the line connects with the tank and connect there and then try again... but if your tank wasn't perfectly clean.. a flake can cover the inlet and act like a valve... i saw this on a tractor in the hydraulics.. a guy blew a hose on his John Deere.. and when he replaced it the hydraulics lost power... he took it in.. they diagnoised a bad pump and rebuilt the pump for $5,000... including labor.. and when it got home it did it again... so he took it to a dealer 150 miles away.. and they said the pump was improperly rebuilt and $5,000 later it came home and the same thing happened... so he brought it to us... and told us his sad tale.. so we replaced the new hose he had replaced with a different new hose... and it worked fine.. the new hose was split inside and under pressure the inside rubber acted like a flap valve and lost hydraulic pressure to that stream... and so we called him and told him to come get his tractor and he asked if we had given up that quickly.. ( he was about 15 minutes from the shop).. and we told him no.. its fixed..
 

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Discussion Starter · #47 ·
Messiest job on this truck to date, and no smoking gun failure point. Had to dig bolts out of the dirt/crud, fuel pick up looks good and no restriction. Will replace the short pieces of rubber hose just because, my best guess now is the lift pump failed. I have a 14psi piston lift pump or another factory Carter to swap in. I was going to try that first, opted to drop the tank and now I regret it lol. Hindsight is 20/20 i suppose.
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Diesel tends to clog up the in-tank pickup filters.
 

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Discussion Starter · #50 ·
Pulled the aluminum fuel line and ran rubber hose all the way. Didn’t see any holes but it was kinked up pretty bad. Will be converting to a draw straw and using one line on the fuel module for the return only. Sadly I will also have to do some plastic welding to undo some botchery:(
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Discussion Starter · #51 ·
Back up and running for now. Got Vulcan draw straw in, and installed piston lift pump. Since I was robbing parts off another truck I went ahead and swapped the fluidamper over too. A weeks worth of work has netted me 14psi of fuel pressure and a noticeable smoother idle. Didn’t have time for an actual test drive, but had it fixed at 2k rpm for at least 30 min with no issues.

need to order the appropriate fuel feed line for this pump, made the original one work after re bending it but I do not like it.

also ended up with another dodge roller. Went for the kp d60 for this truck, left with it all. Lots of good spares
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Discussion Starter · #53 ·
Truck ran great on first test drive, held 9-10 psi wide open pulling a fairly steep grade. Only bummer is amount of rust dust in the pre filter. In 10 miles it was enough to effect the fuel level inside the filter indicating some level of blockage. I’ll just keep popping new ones on till it cleared up I suppose.

super pumped about my new lift that got installed yesterday. Would have really been nice to have during fuel tank drop
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Did that fluid damper actually help with the vibration?
 

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Discussion Starter · #57 ·
This took way too long!

New oil pan to replace smashed/cracked one, jb weld wasn’t holding back the oil and it was quickly rust proofing entire underside of truck.

braced up the previous owners mounts and crossmember. Ended up having to cut middle out and make room to keep from smashing new pan. I should have just started from scratch on the mounts but I didn’t. Lots of cleaning up of flame cut edges

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The crankshaft dampeners have been discussed a lot over the years. A 4bt is a different animal than a 6bt. It doesn't have the harmonics like the 6 cylinder. The stock 6bt dampener provides little or no improvement on a 4bt. The ones that work are the fluid type, either the factory Cummins 4bt unit shown below or the Fluidampr. Neither is cheap. The main thing is they are adding mass to the crank assembly. They weigh 25 lbs or a bit more.
 

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Discussion Starter · #59 ·
Got crusty 60 in along w 52 leafs. Original plan was to move factory leaf mount forward, but frame was so tweaked/welded on/bent that I bought jungles kit which should help keep everything straight. Still a ton of work to do, swapping to new gearbox, crossover steering and go through axle for maint items.
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Got crusty 60 in along w 52 leafs. Original plan was to move factory leaf mount forward, but frame was so tweaked/welded on/bent that I bought jungles kit which should help keep everything straight. Still a ton of work to do, swapping to new gearbox, crossover steering and go through axle for maint items.
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Jungle (Jim) fabs up some great products for our old Dodge trucks.
 
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