Old Topic, New Questions: Chevy 6.2 Diesel Conversion

[The PIG Smith]

Okay, this topic, FSJ Diesel Conversion, is one that has been discussed to death.
I've posted this topic elsewhere on the web,
for I would like to harvest as much info as I can from as many folks as I can.

In my research, I found a lot of talk,
but few nitty-gritty details of what a person can run into while performing this type of engine swap.

Let me start by saying, I’m looking a J20 pickup with its AMC 360 engine out and in pieces.

As gasoline in the US is near or at in some places, the $2.00 per gallon price,
diesel looks like a inviting and fun long term project.

The following info is what I have gathered during my research and is the basis of my preliminary plan.

Engine and Transmission

I will use a 6.2L GM diesel and TH400 transmission.

The 6.2 will be modernized, using a CUCV intake, slightly larger injectors and performance tuned injector pump.
Some 6.5L parts may find their way my planned 6.2.
It will be naturally aspirated at the beginning, saving $$$ for the other details and components for the rest of the swap.
I would like see 300+ horsepower from this engine

I have chosen a 6.2 because it is a cheap and plentiful engine.
The lack of electronics is a big plus for a swap in an older vehicle.
Lots of cheap mods can be made to make the commonly underpowered 6.2 produce plenty of horsepower.

Also, because the 6.2 share the same engine mounts as a small block Chevy and many folks have swapped in a SBC in a FSJ, physically mounting the engine should be a snap.
Much easy than mounting a 6.9/7.3 Ford or 5.9 Cummings.

The TH400 will be built to handle the torque and horsepower of the 6.2.
Once again, because a TH400 has been used in a FSJ, mounting, crossmember and linkage issues should not be a problem.

Transfercase

Transfercase poses a slight issue, as to which one to use.
Because the 1981 model J20 that I planning to use has a driver’s side drop front axle,
then I would need to use a TC that also has a driver’s side drop.

What transfercase will bolt up to a TH400 with no adapters, can handle the torque of a diesel and have a driver’s side drop?

Now for the little details that no talks about:

Wiring

The 6.2 does not have that much engine wiring.
But, how do I found out about the few wires that exist?
What they are for?
Where do they need to go?
Do I need them all or can I eliminate some?
How/Where do I slice them into the existing FSJ harness?

Fuel

Where is the fuel line need to be on a 6.2?
Is it in the right location for the fuel line entrance into the engine bay of a V8 FSJ?
Will I need an electric fuel pump?
What size/brand would I need?

Cooling

The radiator poses another issue, as it would on any engine swap.
I’m sure I could get a custom rad built for a price, but is there any other options?
Cut the core support to retrofit a stock Chevy unit?

Conclusion

Well, those are all I can think of at this moment.

I hope this creates a good discussion.
Your comments, opinions and flames are welcome.
Your support is more appreciated.

[ May 08, 2004, 03:48 PM: Message edited by: The PIG Smith ]

[FSJnovice]

maybe could use a diesel blazer for donor parts, then would be able to see what the few wires that you have to connect actually connect to. what side does a chevy truck drop on check some of the older ones? Fuel line may have to fab up. Cooling the radiator for the 360 or 401 should work, hose routing will or could be different though. Will check on other items though.

[The PIG Smith]

Yes, I think that is how I plan to get the 6.2 and a TH400, from a donor.
I've seen several rusted 2WD rigs that would make great donors

I'm sure I would learn something from a donor,
but I would realy like to have an idea about how to solve some of these issues
before I fill my yard and garage full of project and donor trucks and zillion of parts.

[seamus]

The later 6.2 or first year 6.5 are a good choice for what you want to do . Avoid the pumps on the 6.5 second year and on ... they are what gave these engines a bad name.

[drives mopars]

ya need a better diesel
go with cummins
4 cyc
ya get 200hp easy
or a 6 cyc 5.9 and get 500 hp easy
ive dobe it in a dodge pu
7000lbs 20mpg

[drives mopars]

400 foot pounds 4 cyc
\or 1000 foot pounds w 6cyc

no chevy or ford can match the p7100 pump
with a 6cyc cummins period

[The PIG Smith]

For the reasons I stated above,
I want the swap to be as easy as possible.

While I agree of the three diesels found in modern pickup trucks, Duramax, Powerstroke and Cummins, the Cummings is the best engine.

IMHO, the 6BT Cummins because of its size, would be the most difficult to swap into anything other than a Dodge Ram.

Now, does that mean that it can not be done?
No, I am not saying that at all.
From your sig, you obvious have made this swap,
but can you honestly say that is easy?
Did it in a weekend or two? or four?
I'll bet not.

I think a Ford 6.9/7.3 or a 4BT Cummins would be the next difficult Diesel to swap in a FSJ.
Their size helps the swap, but like 4BT Cummins,
the extensive fabrication makes all the power plants difficult to swap.

I've been beating up on the Ford/IH and Cummins as swap candidates for a FSJ,
for I honestly believe the 6.2/6.5 would be the least stressful and aggravating of a swap.

I've been studying this problem on a off for while.
With the limited resources I have (mostly handtools) and lack of shop space, a welder and other significant tools,
I need to make this swap as simple as I can.

This is the purpose of this post, the gather as much info in order the decide if this project something that reasonably attempt.
There is no doubt that I can pull it off, it's just the time, $$$, tools and space that would prevent me.

Now as far as the 6.2/6.5 being underpowered, this is true is stock form.
Yes, the early units had some teething issues.
But with simple modifications it is easy to get 300+ horsepower from a 6.2/6.5.
This plenty for me.
Are 6.2/6.5 as strong as a modified Cummins, maybe not.

I sorry that you dislike 6.2/6.5 Diesel engines,
but they are great engines, with a dark past and are very underrated.

Maybe I like them because that are considered an underdog. [img]smile.gif[/img]

[fittedj20]

ok the wire you need are the wire going to and from the glow plug temp sensor all the glow plug wires fast idle wire injection pump advance selenoid wire fuel shut off on pump oil pres sensor and the temp and tach sensor
you definatly need a diesel radiator and 250 horses is all you can get out of thees motors even with a turbo and propane you could also try water injection and NOS but you will get great gas millage like 17-21 or so

[drives mopars]

try a web site its close to this
cumminsford or ford cummins

they make kits for ford to install a 6bt in

ive seen a 6bt in a scout and rams

and 4 bts in dodge med size pu

[The PIG Smith]

Thank You drives mopars.
That is a good web with lots a great info.

www.fordcummins.com

They advertise that coming soon:

www.jeepcummins.com

WhooooooHoooooo!!!
I'm gona watch this place closely.
If they come up with the part need to make a 6BT installation that simpton can peform,
then I will eat crow, change my mind and consider a stronger 6BT as a swap candidates.

I suspect, that all the guesswork that I am trying to solve on paper (thus the questions)
these folks has gotten it all figured it out.

[The PIG Smith]

WOW! Check out what fordcummins.com has done!
It's a 4 cylinder Cummins 4BT in a baby Jeep!



I wonder how a person would compare a 2.5 Iron Duke to a Cummins 4BT?
Four Cylinder -vs- Four Cylinder
NOT! LOL!

[Mark G]

I vote for an idea I floated to an engineer at D/Chry i spoke with last week. Why not resurrect the FSJ with more agressive styling like the Rescue and put in the new Mercedes 6 cyl turbodiesel? Why improve on mechanical perfection? Great mileage, astounding durability, and already tweaked by admittedly some of the best engineers around? He liked the idea a lot. I'd just be happy to find and adapter plate, mounts and put a 300 turbodiesel out of boneyard in mine. The thought of having an engine that sounds like a garbage can of marbles rolling around a washing machine drum doesn't appeal to me a lot. If that's a 'macho' sound, I need to watch the movie 'In and Out' and few more times, haha. Tons of room on either side of the engine, save about 200 lbs over a domestic engine, great airflow and low underhood temps, and more HP and torque than my 360 stock. also, 20mpg, hehe. Thoughts?

[ May 09, 2004, 07:08 PM: Message edited by: Mark G ]

[Mark G]

Btw, PIG, I grew up in Fort Wayne! Spent 25 years there. I was a Mercedes mechanic about 10 years there at Maumee Motors. What do you need to get your 86 GW going from one Hoosier to another?
Mark Greven
Bishop Luers '72 (played football too, hehe)

[ May 09, 2004, 07:06 PM: Message edited by: Mark G ]

[porkchop]

Have you guys seen mcinfantry's M715 with a 4bt installed? Here is his page with all the swap info.

http://homepage.mac.com/ltalessi/PhotoAlbum15.html

This is the route I am going to take in a few years when I swap in a deisel.

[ May 10, 2004, 04:58 AM: Message edited by: porkchop ]

[Brule_Cherokee]

Don't forget the Cummins 6at, the 3.4L 6cyl turbo-diesel found in delivery trucks. It's said to be the same overall size as the 292 Chevy straight-6 and has a Chevy bolt pattern. It was an Onan design that Cummins bought and made for a few years and can apparently be found in a variety of large delivery vans. Do a Google search on Cummins 6at and find out more.

[The PIG Smith]

PC, I've seen his site and his video.
I'm sad that his rig was rearended.
I hope he and his oil burner recovers soon.

Thanx for the tip, Brule.
I did not know about the 6AT
I'll search and dig some more info.

[The PIG Smith]

Originally posted by Mark G:
Btw, PIG, I grew up in Fort Wayne! Spent 25 years there. I was a Mercedes mechanic about 10 years there at Maumee Motors. What do you need to get your 86 GW going from one Hoosier to another?
Mark Greven
Bishop Luers '72 (played football too, hehe)

Mark, I am not a native Hoosier.
I'm originally from West Virginia and only been in Fort Wayne about 6 years.
I swam the Ohio to freedom and escaped the Economic Vacuum of my home state.
I love Fort Wayne, but I do miss my mountains and streams.

[mcinfantry]

hey yall. ill chime in on my .02
history/development
the 1979 p-30 chassis i bought originally came with a 350 chevrolet and fitted with an aluminum body for frito lay. in the mid to late 80's cummins WISELY devised a cummins 4bt repower package. frito lay was burning up 350's and fuel milage in a 10000lb gvw truck sucked, literally.
technical aspects
the cummins repower package was a complete, drop in and hook up the fuel solenoid wire, the oil sender, temp sender and emergency shut off wires for low oil/high temp. the package either came with a sm465 4 speed or turbo400 3 speed. the 4bt engine (majority) were turbo charged cpl 858 (model number) 105hp/286tq. a few were 4bta (aftercooled) that were 120hp/300+tq. the trucks were re-fitted at ,i believe, 4 major repower hubs in the U.S. the motor is equipped with motor mounts that the p-30 sees as a stock 350 chevrolet. you bolt it in and its that simple. i can, and have , removed the motor and transmission in one piece in under 1 hour with NO damage to the truck or frame or existing wiring harness. the trucks are well maintained and sold after 24-25 years of service. THE TRUCKS ARE BECOMING HARDER AND HARDER TO GET/ THERE IS NOT AN ENDLESS SUPPLY
my decisions
since i chose this route i knew i was not going to keep the tranny (regardless of type) and i called frito lay, the mechanic ofice for my distribution center. i paid 800 for a running sm465 truck. the clutch was blown but i didnt care. i sold the truck for 350, the tranny, flywheel and adapter plate for 300 and the rims and tires can be sold back to frito lay,if so desired. it should also be noted that the truck has a cab and chassis 14 bolt. i wanted an easy to hook up, reliable powerplant and easy to work on. the motor weighs somewhere around 700lbs, but i did not weigh it myself. it is NOT much heavier than the 230 tornado it replaced. i was not interested in a 6bt because i did not want to cut the inside of the engine bay up for a 1200lb motor.

[mcinfantry]

ok part 2
technical specs
there are no glow plugs on a cummins 4bt. there is no grid heater, but it does have a block heater. yanmar makes a grid heater, original cummins 6bt can also be used if you live where it gets VERY cold. the motor uses a rotary pump, and people have achieved a reliable 250hp/550tq. a majority of the 6bt parts interchange. injectors, water pump, valve covers.... blah blah blah. it has a sae #3 bolt pattern, and comes with a gm tranny adapter. i used stock dodge 6bt to nv4500 adaper.

drivability
i designed my truck to achieve maximum fuel efficency at 55mph to 60mph. as previously posted i get 24mpg at 70mph, and am on the WRONG side of the fuel curve. my truck mathmatically should do 84mph, but actually only does 72-73mph. it drives like a v6 full size truck on road. off road it has no comparison, other than like a tractor. i have 4.56 gears, 38.7" tires and a np205. i have pulled the truck up to a stump that was taller than the front bumper. after locking the front locker (detroit in the rear) the truck idled in first up the stump. you say so? idle is 700rpm. i had my foot off the clutch NO FEATHERING!!! i was able to slow and control the truck ascent by brakes only. it was and remains very odd to drive a standard transmission like an automatic.

any other questions????

[mcinfantry]

CUMMINS 6AT is getting hard to get parts for. they are NOT cheap, and perormance parts are almost 0. the 4bt is a more viable swap. believe me..... i researched it all

CUMMINS 4bt
pros
fuel efficency
parts interchange/availability
durability
simplicity
ease of swap, it "looks" like a 350 to the truck

cons
weight (700+lbs)
initial cost, 2000 for a running truck w th400

CUMMINS 6bt
pros
fuel efficency
parts interchange/availability
durability
simplicity

cons
weight 1200lbs
size, mostly length
must upgrade the front axle, and probably the rear too
2500 to 4000 for the motor only

GENERAL MOTORS 6.2/6.5
pros
cheap
ease of swap

cons
parts will become harder to find a GM has turned ALL tooling over to AM General
reliability? i have NO personal experiance
glow plug/controller issues

[ May 10, 2004, 09:33 AM: Message edited by: mcinfantry ]