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cib
01-02-2012, 20:26
I made a post earlier today but with the updates it appears to have been lost as well as my registration lol, oh well it happens. here goes a second time.

I've got a propane irrigation motor with a chevy 454 engine on it. I'm in the process of rebuilding it but have decided due to all of the added costs, reg being damaged as well as everything else, that it may be economical to swap in a diesel engine. I know of a few 6.2 detroit engines in some local yards that are running with 60-70k on them.

Would this be a good engine to swap in, it doesn't need a ton of power to spin the pump, so economy is a big concern obviously as you want to try and limit fuel use as much as possible. The propane on a hard day could burn 15-22 gallons per hour, we don't run them that hard anymore but it would be required to run in place for 4-5 hours at a time depending upon run length.

I've heard the 6.2 will bolt in place of the 454. Obviously I'll need a diesel tank for fuel supply, would the existing radiator work if it worked for 454? The 454's headers were an edelbrock water sleeve header where the pond water cooled the headers to help cool the engine, would this be a problem, heat meaning, for the detroit? or would a standard radiator work. Also how would the vacuum pump do as a priming pump?

Again I know I'm asking a lot of questions and sorry for hitting so many at once, thanks for any help you can give.

JeepSJ
01-02-2012, 22:21
The 6.2 will bolt in place of the 454. Existing radiator should be fine. I would not use the vacuum pump for anything else. If the radiator is big enough I don't think you would need cooling jackets for the exhaust, but if it is in an enclosed building then maybe you want to dig up some water cooled manifolds from a boat.

What RPM did you run the 454?

DmaxMaverick
01-03-2012, 00:16
As SJ said, it will bolt right up. The vacuum pump will pull 22"+Hg, but is low volume. For priming, use a storage tank (accumulator) and bypass. Start up time is MUCH faster, and it won't (essentially) break. Much depends on the head volume and elevation. If your inlet has a foot valve, it's a piece of cake (no bypass needed). The 6.2L N/A is ideal for your stationary work, which will work happily within your RPM and power demand. Power will be more than the 454/propane, and should net about 50% or better comparative fuel usage (no, really....It's that much). For the cooling, I suggest contacting Peninsular engines (.com) for marine jacketed headers and a heat exchanger. Using a radiator for stationary irrigation is a waste of cooling capacity, space, and man hours. The exchangers cost more initially, but are tiny by comparison, nearly zero maintenance, don't require a fan (or fan belt that will break and shut you down for hours), and mice/rats won't nest in it (or chew your fan belt). Also consider the fuel system. If you use elevated storage, you won't need to worry about a fuel lift pump, ever. This will eliminate over 1/2 of the problems ever seen by Diesel powerplants. Fuel filtration and water contamination control will be paramount, in any case. The standard Murphy switch complement will work with the ESS fuel control (12V required to open fuel to the pump), and the senders will fit in holes already tapped: numerous oil pressure taps, and at least 3 water temp.

cib
01-03-2012, 09:03
The 6.2 will bolt in place of the 454. Existing radiator should be fine. I would not use the vacuum pump for anything else. If the radiator is big enough I don't think you would need cooling jackets for the exhaust, but if it is in an enclosed building then maybe you want to dig up some water cooled manifolds from a boat.

What RPM did you run the 454?

The radiator is really a heat exchanger, didn't think about that. It is a strange shape, a virtical tube that has two horizontal tubes passing through it, the water from the pump, some of it, passes through copper tubing inside of this to cool the water down, I hope this is still in good shape but it is old as heck and has sat up for a couple of years. Didn't think to clarify that earlier, also the heat exchanger is aluminum casting of some kind, as it is very light.

Engine RPM should be ~2500-2700 maximum, we have ran the 454 pulling two guns at 4k but that was back years ago when we farmed a lot more land.

If I can find a "drop in" junkyard special 6.2 what else would I need other than the fuel tank? Are the injector pumps mechanical or do I need a mechanical pump to prime it? Also has anyone ever put a kill switch on a diesel based on oil pressure or water temp? Again I must admit my ignorance of diesel truck engines most of my experience with them is in a tractor, which in many ways doesn't translate well to a truck.

Thanks for the replies.

DmaxMaverick
01-03-2012, 09:52
The radiator is really a heat exchanger, didn't think about that. It is a strange shape, a virtical tube that has two horizontal tubes passing through it, the water from the pump, some of it, passes through copper tubing inside of this to cool the water down, I hope this is still in good shape but it is old as heck and has sat up for a couple of years. Didn't think to clarify that earlier, also the heat exchanger is aluminum casting of some kind, as it is very light.

Read my reply.


Engine RPM should be ~2500-2700 maximum, we have ran the 454 pulling two guns at 4k but that was back years ago when we farmed a lot more land.2200 - 2800 RPM is ideal for the 6.2L. It will put out most of its power in this range, and will run happily all day at this speed.


If I can find a "drop in" junkyard special 6.2 what else would I need other than the fuel tank? Are the injector pumps mechanical or do I need a mechanical pump to prime it?An elevated tank will offer the best protection against contamination (second only to underground storage), and eliminate the need for any fuel lift pump. Priming is as simple as opening the fuel valve. Otherwise, the engine will have an engine driven mechanical fuel lift pump, mounted on the engine in the same location as any typical older GM V8 (which should be bypassed with any other positive fuel supply). With no positive fuel supply (ground level tank), priming will require extended engine cranking, or another pump to lift the fuel prior to start (IF the fuel line was allowed to drain dry, which is a BAD thing). The engine should be shut down with the system full of fuel. Draining the system will lead to serious problems the next time you need to use it. You will need a dedicated high quality fuel supply filter system, so select one with a manual priming pump, and that should solve that.


Also has anyone ever put a kill switch on a diesel based on oil pressure or water temp?These are also called "Murphy" switches. Read above. The fuel injection pump, in OEM form, requires 12V to the pump to open the fuel to the pump. Your existing Murphy system will swap over without any modification. There are plenty of taps for oil pressure and coolant temp.


Again I must admit my ignorance of diesel truck engines most of my experience with them is in a tractor, which in many ways doesn't translate well to a truck.

Thanks for the replies.That's why we're here. That's what we do. Keep it simple. There's nothing complicated with this. I also suggest an oversize oil pan. The original 7 qt. volume is marginally sufficient for stationary use. Make your own (simple, since you have no vehicle limitations), or buy one. Most of what you need can be had from www.peninsulardiesel.com (http://www.peninsulardiesel.com) . They deal primarily with marine applications, which is essentially what you are building.

cib
01-03-2012, 15:25
Sounds good so far, thanks for the info.

I think I may do an inframe style build on it, re-ring kit to this one to just freshen it up but I don't want to spend too much on it unless I have to.

I'm going to look for some oil pans to see if I can find one.

I am curious about the motor mounts, does anyone know how different they are? Not that it matters juts curious.


Read my reply.

2200 - 2800 RPM is ideal for the 6.2L. It will put out most of its power in this range, and will run happily all day at this speed.

An elevated tank will offer the best protection against contamination (second only to underground storage), and eliminate the need for any fuel lift pump. Priming is as simple as opening the fuel valve. Otherwise, the engine will have an engine driven mechanical fuel lift pump, mounted on the engine in the same location as any typical older GM V8 (which should be bypassed with any other positive fuel supply). With no positive fuel supply (ground level tank), priming will require extended engine cranking, or another pump to lift the fuel prior to start (IF the fuel line was allowed to drain dry, which is a BAD thing). The engine should be shut down with the system full of fuel. Draining the system will lead to serious problems the next time you need to use it. You will need a dedicated high quality fuel supply filter system, so select one with a manual priming pump, and that should solve that.

These are also called "Murphy" switches. Read above. The fuel injection pump, in OEM form, requires 12V to the pump to open the fuel to the pump. Your existing Murphy system will swap over without any modification. There are plenty of taps for oil pressure and coolant temp.

That's why we're here. That's what we do. Keep it simple. There's nothing complicated with this. I also suggest an oversize oil pan. The original 7 qt. volume is marginally sufficient for stationary use. Make your own (simple, since you have no vehicle limitations), or buy one. Most of what you need can be had from www.peninsulardiesel.com (http://www.peninsulardiesel.com) . They deal primarily with marine applications, which is essentially what you are building.

DmaxMaverick
01-03-2012, 17:05
Engine mounts are not a problem. OEM 6.2L mounts will fit in place of the 454 mounts. The engine mount to transmission flange distance is the same, as well (no bell housing or coupler modification required).

Unless you find a specific need for rings/bearings, chances are it won't be necessary. Perform a compression check. If it checks out, no need for rings. I do suggest head gaskets, and an inspection of the main webs for cracks (done with the pan removed). If it has good compression and no cracks, seal it up and run it. Nothing will be gained with new rings if it doesn't need them, but you may create problems by doing it unnecessarily. This isn't a gas engine, and the rings/bearings/crank routinely last the life of the block.

If the engine can be ran before pulling, check for a minimum of 10-15 PSI hot oil pressure at idle. 25-45 PSI would be typical at operating temp before a load. You will need to add an oil cooler to your heat exchanger (another marine thing), or fashion an air cooled cooler. The engine will self destruct without oil cooling.

A timing set and water pump would be in order.

It may also need a crank balancer (harmonic balancer), and/or a belt pulley. The later models have an isolated pulley, which must be replaced if degraded. You should only have an alternator driven by the pulley, and perhaps a belt driven governor, if that's what the 454 has (which can be easily adapted).

Depending on your engine source, it may be a J or C code (8th digit of VIN). The C code will have EGR, which is not desirable. This can be disabled, or a J code (or HMMWV) intake can be used. You will have no need for a vacuum pump (one more thing to break).

cib
01-03-2012, 17:36
The vacuum pump was to prime the water pump, it was an idea of priming the system anyway. There are other hand pumps but you'll be the hulk after using them much, the electric ones they are very proud of the ones that can move any moderate amount of air.


Engine mounts are not a problem. OEM 6.2L mounts will fit in place of the 454 mounts. The engine mount to transmission flange distance is the same, as well (no bell housing or coupler modification required).

Unless you find a specific need for rings/bearings, chances are it won't be necessary. Perform a compression check. If it checks out, no need for rings. I do suggest head gaskets, and an inspection of the main webs for cracks (done with the pan removed). If it has good compression and no cracks, seal it up and run it. Nothing will be gained with new rings if it doesn't need them, but you may create problems by doing it unnecessarily. This isn't a gas engine, and the rings/bearings/crank routinely last the life of the block.

If the engine can be ran before pulling, check for a minimum of 10-15 PSI hot oil pressure at idle. 25-45 PSI would be typical at operating temp before a load. You will need to add an oil cooler to your heat exchanger (another marine thing), or fashion an air cooled cooler. The engine will self destruct without oil cooling.

A timing set and water pump would be in order.

It may also need a crank balancer (harmonic balancer), and/or a belt pulley. The later models have an isolated pulley, which must be replaced if degraded. You should only have an alternator driven by the pulley, and perhaps a belt driven governor, if that's what the 454 has (which can be easily adapted).

Depending on your engine source, it may be a J or C code (8th digit of VIN). The C code will have EGR, which is not desirable. This can be disabled, or a J code (or HMMWV) intake can be used. You will have no need for a vacuum pump (one more thing to break).

DmaxMaverick
01-03-2012, 18:30
The engine driven vacuum pump could be used, but you'd have to start a day ahead of time. I suggest a belt or shaft driven pump.

How much head/volume are you pulling? What method/device was used before? There are other options, but I'd like to know more about your situation before suggesting them.

DmaxMaverick
01-03-2012, 18:37
By the way.....
Years ago, I designed and built several similar pump systems. Wind machines as well (citrus groves). Oddly enough, most of them were 454 and 360 propane. Gas was an option for a couple of them, but the gas always seemed to evaporate at 10 times the rate it should have (defies science).

Vacuum priming is, well, primeval. There are MUCH better, faster, (and more reliable) ways.

cib
01-03-2012, 18:51
By the way.....
Years ago, I designed and built several similar pump systems. Wind machines as well (citrus groves). Oddly enough, most of them were 454 and 360 propane. Gas was an option for a couple of them, but the gas always seemed to evaporate at 10 times the rate it should have (defies science).

Vacuum priming is, well, primeval. There are MUCH better, faster, (and more reliable) ways.

Priming 8" piple that is at 45 degree angle about 8-10 feet in length, the vertical drop is maybe 4 feet from pump. So not far to pull up height wise but distance it is a fair amount.

The propane engine worked great and lasted forever but it just burns too much fuel for us and it would allow us to get rid of the propane tank and purchase ag diesel at a cheaper rate.

Gas I've heard of the same problem, though I know people who run it because it is cheap to build.

Glad this conversion doesn't sound as bad as I figured it could be.

DmaxMaverick
01-03-2012, 21:20
Heck! That's relatively small. I thought we were talking about much bigger. Most of them around here are 12"+, with a head of more than 20'. We'll get you up and running. 4' head and 10' on an 8" pipe is minimal, but still not ideal for vacuum pulling. A small water pump (gas powered or electric) or a 100 gallon storage tank (which will pay for itself in no time) will do the job in a minute. You only need a valve on the suction pipe near the source water level, then fill the pipe from the outlet side. A centrifugal 8" pump will tolerate up to 40% air during run-up. Fill the pipe, start the main pump, open the suction valve, off and running. If you install a foot valve on the suction pipe, it will simplify the whole process, and speed up the start time significantly. Time is money (or a loss of family time).

cib
01-03-2012, 21:27
We've already got the valve was just thinking of a way to prime. The old system used the vacuum from the engine to prime it, god it sucked when that old engine was worn out and had no vacuum lol.

Yeah this one pumps water from a pond and is nearly at water level, only a foot or two above the water level, then the angle of the pipe into the water. It is an 8" pipe but has a 10" pipe that slips over it with a cage on the end but when we put it in the water it is not far away.

We have pumped it down a lot in years past but again we don't farm nearly to that level before. I used to chuckle when berkeley said their pump wouldn't pull two guns on 6" pipe, I told them we've pulled two guns at over a mile of 6" pipe, that fuel bill SUCKED.


Heck! That's relatively small. I thought we were talking about much bigger. Most of them around here are 12"+, with a head of more than 20'. We'll get you up and running. 4' head and 10' on an 8" pipe is minimal, but still not ideal for vacuum pulling. A small water pump (gas powered or electric) or a 100 gallon storage tank (which will pay for itself in no time) will do the job in a minute. You only need a valve on the suction pipe near the source water level, then fill the pipe from the outlet side. A centrifugal 8" pump will tolerate up to 40% air during run-up. Fill the pipe, start the main pump, open the suction valve, off and running. If you install a foot valve on the suction pipe, it will simplify the whole process, and speed up the start time significantly. Time is money (or a loss of family time).

DmaxMaverick
01-03-2012, 21:54
The only lift that matters is the top of the water level to the pump. That's the "lift-head". The pipe volume doesn't matter, except for priming volume. If you already have a valve at or near water level, you only need a storage tank to fill the pipe for priming (at least 2x the pipe volume). It's easy and free (doesn't require any other power source). The tank is filled once the pump is primed, then ready for the next run. This is why it is plumbed into the outlet side of the pump: Fill the pipe for priming, engage the pump, then fill the tank for storage once the water flows. Simple, and darn near idiot proof.