6.2 700r4 conversion in 88GW

[charleslriddle]

This is my story of the diesel conversion of the GW. I have many questions, and wanted to document the process on the forum so others can get answers to what I've posted. Building the knowledge base.

Donor: 1991 GMC Suburban 6.2 diesel non turbo

I've read all the threads for the past 2 years planning the great conversion.

Below is a picture of the Donor towing the Donee, which is now stripped of the 360 and 727. I kept the np 229 and will use the novak adaptors.

Thanks everyone in advance for your help!

[charleslriddle]

First Question - Fuel Lines Set Up

The first thing I am thinking through is the fuel line set up. Can I use the lines sized as they are? Can I use rubber hose, braided flex line, or hard plumb the line? Where should I put the electric fuel pump? How should I wire the Fuel Pump? Do I need a safety shut off?

Thanks

[joe]

Personally I'd keep the barn door dsl burb and shake off that thing hanging from it's butt.

[Greeeeenberg]

Agree with Joe. That burb looks clean.

[KaiserMan]

Personally I'd keep the barn door dsl burb and shake off that thing hanging from it's butt.

Hate to say it, but ditto. Unless that Suburban is a rotted train wreck in person, I'd drive the burb and find a drive train elsewhere.

[710 Burner]

My plan is to use the frame mounted lift pump and 3/8" hard line, but the stock 5/16 line would probably work good.

[The PIG Smith]

Hate to say it, but ditto. Unless that Suburban is a rotted train wreck in person, I'd drive the burb and find a drive train elsewhere.

X3
If the Suburban is 3/4 ton rated, then by all means keep it, drive it and use it.

I ran into this same issue with my Diesel powered van.
Use the 6.2L from the van for a FSJ project or not.
The van was in too good of shape to part out, so I fixed it and am now driving it.
A one ton extended length cargo that sips Diesel fuel has been super handy.

[710 Burner]

I failed to mention that my donor is a '97, so that is why it has an electric frame mounted lift pump. The lift pump on a 6.2 is typically a mechanical unit mounted to the block.

[charleslriddle]

Burban Rotted

The suburban has 255000 miles on the chassis. I may keep it, but I'm definitely taking the 6.2 out of it. It was rebuilt and put in the suburban by a diesel mechanic - so I know it's good.

The suburban is 3/4 ton. Plus it has all kinds of upgrades. It was an off road paramedic truck. Put stock seats where the stretcher was. All kinds of interior lighting and switches.

This thing is rotted to sh it. So - It may go to parts when I'm finished. Unless I find another 6.2 to put back in it.

I towed the GW from the cuts of Philadelphia across many shady places about 40 miles away to my place, and the motor was strong. I'm stoked about putting this beast in the luxury of the GW.

[The PIG Smith]

I towed the GW from the cuts of Philadelphia across many shady places about 40 miles away to my place, and the motor was strong.

Do not let the naysayers beat you down.
The 6.2L in my van runs strong as well.

[charleslriddle]

Do not let the naysayers beat you down.
The 6.2L in my van runs strong as well.

... and The Legendary Pig Smith speaks. Heed his word!

[charleslriddle]

Fuel Set Up - Plan

OK- Here is my plan for the diesel swap fuel set up.

The lines (feed and return) run up the drivers side rail on the GW. The 6.2 needs them on the passenger side. I thought about redoing all the lines and running them up the pass side, but I'm not going to do that. I'm using the existing lines - connecting where they terminate in the engine bay - and crossing over (probably with rubber fuel lines) under the radiator crossmember.

Any objections or comments to running rubber fuel hose along that radiator crossmsmber to get it over to pass side?

I'm also going to set up an electrical fuel pump in the inside frame behind the gas tank in the area of the GW spare tire bay.

I'm not 100% about taking the mechanical fuel pump out of service. I may run a loop around the electrical pump so the mechanical pump does not have to suck through the electrical pump. I'm looking into a fuel check valve for the loop so the electrical pump does not short circuit through the bypass.

I may just use the electric pump to prime / bleed the fuel system clamping off the bypass when priming. Then normal duty i'll open the bypass and let the mechanical pump do it's job. Leaving the electrical pump off.

[rustywagoneers_com]

Electric pump for the win.

[budojeepr]

Diesel fuel rots rubber. Get the best quality (fuel injection) hose you can afford.

[charleslriddle]

Fuel Lines

10-4 on the rubber fuel injection line $6/ft.