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!

http://farm2.static.flickr.com/1235/5118640190_57a6272cd9_b.jpg

[charleslriddle]

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]

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]

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]

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

[charleslriddle]

Everything is nice and pretty. The toughest thing was coring out the filler tube so I can put diesel in it (the spout is wider). I used a 1 3/8" core drill bit I hade laying around. Then blew out all the filings with the compressor.

There is a vent tube connected to metal line coming out the top of the NP 229 where did that connect to / or where should it have connected to? I offered the engine and Trans to a guy if he took it out, so I didn't see where the hell this line connected???

I figured out what it is - it's a vent line that ran up near the cylinder head and was open to atmosphere.
http://www.ifsja.org/forums/vb/showthread.php?t=34541

[charleslriddle]

Background - I'm in process of converting the GW to 6.2GM diesel non turbo backed by 700r4.

Looks like money will fly from my pocket and I will buy the aluminum conversion radiator and electric fan set up from BJ's. That set up will provide me with coolant and trans coolant. I'm planning on keeping the aux trans cooler in line with the new rad. (or should the new BJ's be sufficient?)

I still need to handle the oil cooler. It looks like there is room for an oil cooler. Any thoughts on what is the proper size for the application?

Any comments on how other swappers handled their oil coolers?

Thanks in advance!

[710 Burner]

My opinion...
I would put a metal line across the front and connect the ends/radius' with the rubber.
I love the comment about diesel rotting rubber lines. GM used alot of it. I have a rubber line running from the fuel filter to the IP under the intake.

[budojeepr]

My instruction re: rubber hose comes from my diesel VW TSM. Are you sure the GM lines are truly rubber? I just wish to err safely. Car fires suck.

cr, your cooling scheme sounds like it'd work. I ran into space constraints and had to move the radiator forward. I hope yours comes out better.

I got an oil cooler from a Grand Cherokee and first mounted it inside the driver's side hole in the front fascia (next to the headlight). Conncting the lines to the cooler there was problematic and resulted in a nice engine oil bath one dark day. I ended up putting the cooler under the ds floorboard, where it seems to working nicely.

[710 Burner]

Hard to say. German rubber is strange stuff.

[NWA Grand]

I'm planning to swap a 6.2 into my Wag as well, I'm going to be doing it over the winter. In my daily driver, 88 chevy 1500, 6.2L diesel I've replaced alot of the fuel lines with oil/tranny cooler line, mainly because I'm running up to 80% WMO, and it works great, i've had zero problems with it. My donor rig is also a Suburban buy mines an 85 2wd 3/4 ton, but its got the TH400(so i'm just swaping tailshafts) and 4.10 gear 14 bolt in the rear, and not near as nice looking as the one you've got, but I paid $400 for it and drove an hour home.

[charleslriddle]

Conncting the lines to the cooler there was problematic and resulted in a nice engine oil bath one dark day. I ended up putting the cooler under the ds floorboard, where it seems to working nicely.

I was up the local junk yard, and I have a 6.2 to pick from. The doner does not have all the pickins, but that's a different story.

So, the junk yard 6.2 has an oil cooler about the size of a phone book (a bit thinner) and the lines are in nice shape, so I'm going to try to pick them, and hopefully mount in grill. We shall see.

Budo - The floorboard idea is ingenious. Let me get this straight, you have it stuck up there like a stick up (horizontal?)

I'm nervous about engine placement. These questions are just warm ups.

[charleslriddle]

4.10 gear
Yeah - I think the burb has 4:10s as well it's like a school bus - revs high on the highway. The 6.2 should purr nice running 3:31s at highway speeds. I'm going to take the GW tires up to 31s or 33s to get better (lower highway rpm) total gear ratio.

I was planning on having this finished by new years - The donor inspection expires in april. The donor burb also does not have windshield defrosters :( and the front tires are bald. Not a dime will go into the burb. Not a dime!

Good luck with your conversion.

[jeepjerry]

Im staying subscribed. Cant wait for pics. I want to do a diesel swap of some sort in the future.