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6.5 Turbo Fuel System Diagrams (and advice)needed

Guys, you're all my heroes! Maxine is rockin' better than I could have ever hoped! It's amazing how much git-up-n-go the old gal has in her now that she's getting more fuel and less air!
MUCH gratitude to all for the advice. I'm by no means an expert on 6.5's now but am a lot more confident in working on the top end!
THANK YOU!!
BTW, wet pavement + LOTS more horses equaled a 180 getting on Hwy 49! YIKE!
Just changed the signature block for Maxine.
 
No problem, just take the down times in stride ;)

To make sure she stays happy, put a quart of TCW3 2-stroke oil in the fuel tank each full fillup. And make sure to get a remote mount PMD/FSD ASAP, sometime that will even make it more responsive and certainly more reliable.

And make sure the Lift Pump (LP) is strong. Need a fuel pressure/vacuum gauge. Read up all about it HERE. read it a few times, paying close attention to what applies to OBD1 trucks, which I posted in posts 29 and 30 of that thread. You have an OBD1 truck, and each year has slightly different quirks. You should check LP, and purge water/contaminants from from the filter manager at least every oil change.
 
10-4, Buddy. Very good advice. Will do.
Soon as the Saint's get finished whoopin' up on the Cards!
And basking in the afterglow; mama keeps giving me hugs saying Thank you, thank you, thank you!
 
buddy said:
... And make sure to get a remote mount PMD/FSD ASAP, sometime that will even make it more responsive and certainly more reliable....
Click to expand...
Can I make this mod without removing the intake again? Sounds like a very good thing to change next.
 
CptTrog said:
Can I make this mod without removing the intake again? Sounds like a very good thing to change next.
Click to expand...

Yes, buy one of the remote mount kits with heat sink, pmd and extended cable. Unplug the heatsink in the stock location and plug in the extension cable. Leave the old PMD in place, not going to hurt anything.

If you have just replaced the IP with a new one having a new PMD on pump or just replaced the PMD, I've heard it's possible to remove the PMD with out disassembling everything but it is a MAJOR PITA!!
 
Yes as stated, unplug PMD on IP and go from there. Mount it in the bumper is best. Just put some RTV around the outside rim of the mounted PMD to seal out moisture.

I'd agree PMD relocation is #1 mod, and making sure LP is running is #2, which involves the OPS relay mod for an OBD1 truck and frequent pressure testing. In 94-96 I think had the weakest spec'd LPs as well, so getting an aftermarket Walbro, or a 93 spec'd (direct replacement) is a good idea.
 
I still did not see a diagram of the fuel routings after everything that was posted on this thread. I have a 1993 k3500 and just did a head upgrade and cooling upgrade with new timming chain and I also need the fuel routing diagram. II am now getting smoke that i didnt have before the changes. I have the same mechanical IP and a aftermarket lift pump both of witch I HAVE Not changed. The truck ran great before the upgrades. I only started with the cooling upgrade from Heath Diesel but decided to pull the heads also and found cracks. So then i ordered new heads and installed my old Precups in with nerw Head bolts and timming chain. and I cant remember exactly how the fue lines went. I used the drain to plug a line when i pulled them and now still am unsure I have it correctly to diagnose my heavy smoke issue Im having now.
 
So for clarification are you talking about the hard lines from the IP to the injectors or the lines from the tank to the filter and then to the IP?
First thing I'd check for smoke is the air filter and then verify the turbo is working properly.
 
I dont have the air filter on right now and the turbo is fine. I need the diagram for the soft lines to fuel filter manager to the Injection Pump.
 
I dont have a map sensor or any other senser as my truck is the last year of the Mechanical with NO computer and the First year of the TURBO>
 
its line from tank to lift pump to filter with 2 out lines . thats ware im stumped as the 2 out line from bottom of the filter /waterseperater. my IP has a line that is in the middle of the out to injecter lines and another on top that is a return or maybe I have them backwards. Thats what I need to know
 
So the 2 out lines as you call them, the larger one goes to the IP and the other smaller one is the water drain. The water drain one should go to a T valve towards the front of the engine. Coming out of the IP is the return line that connects to a metal line that goes to the injectors and connect to the two nipples. That return line eventually goes back to the tank
 
the 2 outs on the FFM are the same size in diameter. there is one in the center and one to the drivers side. there is the word "OUT"stamped in between both outs. Im assuming the out in the center goes to IP inlet and the othere to my bleed valve.
 
Listing truck details in your signature line helps us help you so we can read it with each post as needed.
If you can post a couple pics of your ffm- that will help identify which one you have and be sure we tell you which is which.

The water in fuel sensor is the 3 wire part on the side. The drain is NORMALLY the one next to it. If you look closely at that side you should be able to find the word drain there. There were a few different versions of the ffm over the years, and thr hummer one is slightly different with a 90° Bend in it’s fitting, (pics below) but they still have it in same location afaik. Diesel fuel on an old toothbrush is usually best way to clean out junk built up around the words to read them.
5472BCDE-1A5D-4226-AD4C-D68B2BE14D56.jpegB46B56DF-F91C-4E7C-8855-8094B6BF2DA5.png

Your db injection pump (db0,2,or 4) can be read on name plate of it. The input line is in the rear, middle of the 8 hard injection lines. Factory for gm is 5/16, but on ford and most all equipment is 3/8. 3/8 is better and a good upgrade to do, requires 3/8 output modified from ffm obviously. The return from the ip (injection pump) is 1/4” and about 5” long, It is good practice to replace this with clear tubing to identify air intrusion contamination of fuel, verify fuel flow, etc. There is fuel rated clear, but most folks just get the cheap stuff at a hardware store and replace it every few years because it’s so easy to reach and so cheap.

I always suggest putting in a hard “Tee” at the ip inlet and attach a fuel gauge there which can be read while driving. Low fuel pressure destroys ip. Bad lift pumps make the same sound as good ones. Your db pump if not a hortrod modified pump should max at 5psi. From 5-8 psi it will advance the engine timing. Above 8 it will create real problems.
 
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