1995 kodiak propane 502ci swap into 84k10 jimmy?

[jhasty4]

has anyone ever pulled and used one of these? i got a hijack deal possible to get one for my 84 jimmy but i dont know what all i need to pull or if its worth it. anyone able to chime in?

[gmcxt]

Theres no replacement for displacement, Id run it. Whats the specs/uses of your Jimmy?

[trkklr77]

is it a bbc based motor?

[jhasty4]

yeah its big block. the one i looked at(the guy has a shat ton of old runnin schwans trucks) was a 502 goin by the rpo codes. its a k6500 kodiak .they are all propane driven. i am a propane newb.
the jimmy has a used 79 350 i just put in and spun a bearing and 700r/208/10&12 bolt axles. yeah i know about that shat-axles. its trail only. i only had it bout a year and been thrashin it til i get all the parts i want so i can build it at once. got a 14ff and matchin 60 front at the house been tryin to decide on trans and t-case. was thinkin bout matin it to the 700r/208 til i figure out how i wanna go or blow them up.
like i said though i know nothin bout propane let alone what all i need to pull out of this truck. the chevy "fleet servicing" dealers in cincy dont know shat either. been searchin and searchin but only stuff i would recognize is the stuff i have seen here.hell i am half tempted to post pics of all it and hope i get a little help as opposed to burnin.lol.

[jhasty4]

on top of that i am tryin to find out what limiters or restrictions are on it. sure it has some sort of rev or speed limiter it is a newer 26000lb truck

[azcagiva]

All the medium duty trucks that were factory propane that I have seen had the 454. Gm put in the 8.1L in 2001+.

All it would take to get it to run would be to put an older hei distributor in it. You would then need to make sure the 425(propane carb) has the right airvalve in it. With the correct airvalve and HEI distributor it will run without a computer. You will need to do some research on which flexplate will work with the bb/700.

The factory computer shuts em down around 3800 rpms.

-John

[jhasty4]

hmmm well iwill just make the kiddos eat ramen noodles for awhile and pick a different tranny/tcase setup. crack head soup will toughen them up.

or maybe pull the tranny too and get a divorced case

gonna go look and see if any are 454 i think. they arent goin anywhere fast. from what i know its a much bigger aftermarket

[Pistonman]

If they are tall deck I don't think they are any kind of a performance engine.

[noface]

I've never seen a tall deck 502. Of course that don't mean jack...

If its a tall deck engine, then it's likely a 454 or 366

[azcagiva]

I need to make a correction I believe they went to the 454 in the medium duty when they went to the vortec motors(98-99). So the OP's engine could be a 427 truck which would have a tall deck in it. It is a low rpm engine, but will have a forged steel crank in it. Gm uses a tall deck block for the 572.

-john

[jhasty4]

Originally Posted by azcagiva

All the medium duty trucks that were factory propane that I have seen had the 454. Gm put in the 8.1L in 2001+.

All it would take to get it to run would be to put an older hei distributor in it. You would then need to make sure the 425(propane carb) has the right airvalve in it. With the correct airvalve and HEI distributor it will run without a computer. You will need to do some research on which flexplate will work with the bb/700.

The factory computer shuts em down around 3800 rpms.

-John

maybe i cant read rpos or have a wrong list of some sort but i swear its a 502 based on the one i have.

[azcagiva]

If it is cheap get it.



-John

[the_experience3006]

The 502 was offered in MDT's...

[jhasty4]

trust me i aint talkin shat i have pulled axles based on rpo codes just cause i was in a rush and been wrong before. fawkin aftermarket!
just dont wanna pull and have no use for it either.no offense azcagiva but i am tryin to verify the hei distributer and airvalve replacement to make it run in my pos. havent been able to find much info though or i am to handicrapped to use the search function. startin to think i am the only one to rob a stock propane motor out of a medium duty truck. closest i have seen is the yota guys and yota forklifts. is their a guru on bbc or propane on here i need to harass for the info? or a thread that comes to mind?maybe i should just buy the whole truck and worse case scenario just put the k5 on that massive 8" straight c-channel frame.

[azcagiva]

Can you post a picture of the engine? Take the top of the carb off and look at the small cone on the airvalve. If it has a 51 it will run too rich, any other number will work. If the engine has a distributor you can replace it with an HEI, If it has the coil packs on the valve covers probably not.


I would also go talk to the mechanic at the local schwans warehouse. They would be able to tell you better than anyone. I deal with medium duty propane delivery trucks. I wish we had some 502 versions, all the newer stuff is the 8.1 and now they are no longer making them.

-John