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Fuel setup on 6.2-6.5 hybrid need help.

BBB82

BBB82

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New Bern, NC
Here it is I have a 1982 k5 blazer non -milt, all power opts, had AKA red block 6.2 in it now it was replaced with a 1986 6.2 block 40 over, 6.5 heads, GM8 setup with heath diesel turbo master, with that my mech pump on the block was out of the question still have the primary fuel filter on the pass side firer wall no secondary with 6.5 intake setup, also have kennedy diesel Duramax lift pump with control harness. Now for the hard part:

1. But the lift pump before or after primary filter?

2. Get a secondary 6.5 HO fuel filter setup from walking J or not need secondary filter?:hihi:
 
Well, from the factory, the 93 and up 6.5 trucks only have 1 filter which is after the LP.

In my opinion, if I were designing or building from scratch like you are, I would put 2 filters on it..... A primary filter (with a water seperator bowl) between the tank and LP to filter out junk before it gets to the LP. Then a smaller micron rating secondary filter between the LP and IP to filter out smaller pieces of dirt or anything from LP if it starts wearing or whatever.

Might be overkill, but that's what I would do.
 
A stock LP from a 93 6.5 pre filter is all you need. That is the way my 93 is setup with a turned up IP and TM and I run about 10 psi at idle and 4-5 psi WOT. Anymore than that is a waste of money as the inlet on the DB2 can only take so much fuel anyway.
 
Acesneights1 said:
A stock LP from a 93 6.5 pre filter is all you need. That is the way my 93 is setup with a turned up IP and TM and I run about 10 psi at idle and 4-5 psi WOT. Anymore than that is a waste of money as the inlet on the DB2 can only take so much fuel anyway.
Click to expand...

Yours would be an exception and not a rule. never seen a stock LP do 10 psi at anytime. Most stock LPs run 5-6 and drop to zero at WOT.
 
He was asking about what filter to use or where to put the filter in the system wasn't he? Now you guys have me second guessing whether I read it correctly or not...... :(
 
The fuel feed line jumps the frame rail before the doors on a 82 k5 blazer so I was going to put the Duramax lift pump there were the hose is not a steel line. It is feed from lift to right so that should work. Now my upper and lower intake manifolds are new so I had to get a used fuel filter that bolts behind the upper intake and bolts, filter, about to drill out for a 3/8 fittings all the way into the fuel pump. Hope it works.
 
Installed my new lift pump on the frame rail just under the pass door. Called Kennedy Diesel they stated that the pump is set at 3.5 psi but high flow. I read that a lot of you guys are running 7-8 psi. I hope I didnt get taken with going with this pump. I will add pics when I figure out how to.
 
PSI isn't important. The IP does all the pressurizing that's needed. Fuel flow is more important. It lubes and cools the IP so the more fuel flowing through the better so long as the return system can handle it
 
s-mack said:
PSI isn't important. The IP does all the pressurizing that's needed. Fuel flow is more important. It lubes and cools the IP so the more fuel flowing through the better so long as the return system can handle it
Click to expand...

Wouldn't low pressure affect the flow though?

Good to see another Mack on here.

BBB82, are you talking about the rectangular filter for the 6.2s?
 
Yes I suppose it would depending on pump outlet and fuel line size. The point I'm making is don't worry about what the lift pump PSI is so long as it's rated for LESS than 14psi. Worry about gph. What the number needs to be I couldn't say but at the absolute least a quart a minute I'd guess
 
No jmack91z28, It is a 82 with the crew on round filter type I think the rectangular stye came out in 86. I also found that the lift pumps to can be easily compounded, I dont I will need to.
 
Like I said before, use a stock LP from a 93. My readings are consistent. Leroy you and AK are referring to #'s on a DS4. He is using a DB2. My pressure #'s are consistent on three DB2's I owned. As far as the fuel filter LP goes pre filter as close to the tank as reasonably possible. It will work anywhere even in the engine bay but closer to the tank is better in the long run. As far as filter I never really liked the later 6.2 filters. They have a tendency to leak. I think FFM from a 93+ 6.5 is the way to go but I am not sure on the wiring as far as the WIF or fuel heater but I am sure it can be done if the schematics can be found. I had the oil style dual filter setup on my 83. I shitcanned the little under the intake and used a better filter on the main filter head but that was along time ago and don't remember what filter I used. I think it was a cat filter but don't remember which one. We had them laying around the shop so I tried a few different ones till I found one that fit. As long as it screws on and has a decent micron rating and can absorb water any filter can be used. I think it was off a 963 Cat but I am not sure of that. If I did it now, I'd just find a used FFM and wire it up from a later model 6.5TD. BTW you could use a later model 6.5 FFM and not wire it in at all. Just wowuld have no WIF light or Fuel heater which the original 6.2 setup didn't have anyway(the heater).
Also 3.5 PSI is too low. 7-8 is where you want to be on a DB2 or the advance may not work properly as it works off fuel pressure. Too muc is no good, too little is no good. A stock 93 LP is the perfect LP as it was factory equipment on the 93 6.5TD DB2 equipped.
 
When i built my setup as i was swapping over to the Banks turbo kit i installed a Holley Blue LP right at the joint behind the doors that BBB82 spoke of. I used a tubing cutting and cut about 3-5 inches out of the lines of either side then used compression fittings to re attach the little barbed ends for the hoses as i saved them.

Here's pics.

IMG_20110528_232608.jpg

IMG_20110519_214131.jpg

That pump puts out ~14-15 psi all day long. I installed a regulator behind the CDR valve which limits the pressure to ~7.5 psi. When i rev the engine the needle doesn't even twitch off 7 psi.

On all the 93 "HO" LPs i've used, none have performed consistently. They'd all start out running ~8-10 psi idle and would drop even with a free rev of the engine. I never checked what my fuel pressure was at WOT, but i have a feeling it was barely anything.

In fact i exchanged probably 3 or 4 of the damn Airtex E3158 93 "HO" LPs under the 1 year warranty for failures.

I wouldn't waste your time with one, and that's coming from someone who ripped it off his truck after fighting with varying pressures for close to 2 years.
 
There is the setup I went with before I found out what everyone is running cant bring back now.














Got a used FM I will be trying to wire everything in. Also my blazer did come with a fuel heater it sat in the middle of the block under the intake man.



 
i'd re-use that fuel heater. It's very simple to hook up. Just trim the fuel lines a bit with a pipe cutter, double clamp the hoses, and you'll be all set.
 
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