Engine swap diesel vs. gas

I'd pop the valvecover and take a look at the rocker arm, making sure it's not broken and that it's pushrod isn't bent.

Keith

On Sat, 09 Oct 2004 04:11:51 +0000, The earnest one rearranged some electrons to form:

blown head gasket between 6 & 7?

considering

That was the first thing I did after compression check. Valves working properly on both #6 and #7, no bent P-rods. I'm going to yank the engine out soon and pull the head. Will let you know what I find. Sure is puzzling.

That is certainly suspect but I've never had a cylinder produce virtually no compression, even with a bent valve, blown head gasket or hole in piston. Thing is the engine runs fine except for those two cylinders. No water in oil, no oil or bubbles in water (normal if gasket blown in water jacket area), and what very puzzling is that the exhaust on that side (dual exhaust system) runs cold while the other side is hot. I can understand that if the other two cylinders (#5 & #8) wern't firing but they are producing power!? Also, if it were a headgasket in the water jacket area I would (normally) have moisture at the exhaust, but there's none. Will let you know what I find when I pull the head (after engine pull). Would still like to know more about a diesel swap.

"The earnest one" had writtennews:byJ9d.8662$ snipped-for-privacy@newssvr13.news.prodigy.com:

Don't do it. I drive truck for a local welding company and they attemted just that. The cost was secondary to the end result. It's not just sticking a diesel in but all the other things needed. (Fuel tank etc.) End result? The engine blew shortly after. They ended up leasing a F450 and buying it later. Get a truck with a diesel in it.

On Sat, 09 Oct 2004 19:33:10 +0000, The earnest one rearranged some electrons to form:

I agree with the other posters... it would be easier to sell the truck and buy one with a diesel engine.

Have you checked the difference in the cost of an engine/trans assy compared to the cost of a diesel truck?! Diesels normally don't just blow up. Also, why does the fuel tank have to be changed? If the problem is simply a return line that is easily achieved. I currently have two 20-gal tanks on the truck and everything else is set up exactly like I want it...receiver hitch,

2,500-lb air bags, brake control, 1200 x 16.5 rear tires, dual front shocks, no California smog requirements, etc., etc.

The tanks don't need to be changed _IF_ they are plastic. You absolutely DO NOT want to put diesel in a galvanized container. Plus you won't need the electric pumps in the gas tanks anymore, you'd have to change the pickup units. Easy to buy a properly built truck. You're looking at a real PITA to convert one.

s

Because the diesel runs on a PRESSURIZED closed loop fuel system, just like the fuel injected gas trucks, you will need all the tanks pumps and fuel line from a donor truck. That includes the emergency fuel cut off switch for your electric fuel pumps etc.

I have done the comparatively simple conversion of two carbureted gas Ford trucks to electronic fuel injection from the same cubic inch donor Ford trucks. Even if you were dealing with the same year diesel donor truck as your truck it would still be FAR easier and less expensive to sell your gas truck and buy a factory assembled diesel truck.

By the way a new replacement Cummins bare block is over $5000.00...

The '73 F250 does not have pumps in the tanks, or a closed loop pressurized fuel system. The tanks gravity feed to the mechanical pump on the engine block. And you are right it will be a real PITA

Yeah, the anti-cavity small block....

pressurized

Okay, next possible route. Put a late model Triton V8 in with the proper tranny (C6?). Thing is I don't want to fool with all of the garbage associated with fuel injection...computer, sensors, etc., etc. Is there an after-market intake manifold that can be bolted in place on a Trident V8 for a 4-barrel carb? I have a machine shop and can machine an aluminum plate to do essentially the same thing using the fuel injection manifold but haven't looked at one closely enough to see if the proper cylinders would be fed from the carb ports. As you have probably guessed I don't want to simply sell the '73 and get a later one because I'm then required to get annual smog checks, etc. When I had to get the truck smog approved in the past (prior to the abatement date for smog checks on '73 and earlier) the cam and bore job gave the technician fits. The truck would barely run and I had to advance the timing from AFDC to the proper 13 deg BTDC to get it to run again. If you haven't lived in California you have no idea what they have done to make life difficult (if not impossible) for older truck owners. They simply want you to drive it off a cliff (or let it makes its way to Baja via the theft route) and buy a new truck and pay $600 to $900 in annual license fees. I still have to pay almost $150 per year for plates even though this truck is over 30 years old! Any hot rodders out there who've fooled with the Trident V8?

Find another 390, 360, or 352 long block, rebuild it, then swap it in using your existing peripherals.

....and you're done.

Spdloader

What HE said.

s

Trident??

LMFAO!

"The earnest one" had writtennews:N62ad.9507$ snipped-for-privacy@newssvr13.news.prodigy.com:

Used Diesel Engine! It didn't blow up persay but the block cracked and the rack did as well. Computers had to be re done for specific year. The Diesel was not the same year as the truck and very hard to get it through the "learning Cycle". But in any case I apologize for giving you the advise. I promise not to do it again. Go ahead and do it.

I have to throw in my 2 cents worth. I would NOT recommend doing a diesel swap, this would be a MAJOR refit. If you did get the diesel engine (powerstroke?) to bolt up to a C6 transmission, I doubt that the transmission could handle it. Think about it: the diesel will run half the rpm with twice the torque into a transmission that is designed to use high rpm for pump pressure settings. The only practical way to put a diesel into an older pickup would be to find a gently wrecked pickup with ALL of the components and change out the complete engine, transmission, electrical components (newer diesels are electronically controlled), radiator (it's quite a bit larger), intercooler for turbo, brake system on firewall (power brakes no longer work because of no vacuum in diesel engine), exhaust system (generally much larger pipes on diesel), etc. I think if you pull the head off of your current engine you will find the head gasket has a burned through area between the number 6 and 7 cylinders but not burned into the water jacket. In other words, you are basically running a 6 cylinder engine. I have seen this on Ford engines before and they run surprisingly good, except for gross lack of power.

and what very puzzling is that the exhaust on that side (dual exhaust system) runs cold while the other side is hot. ....

That is kind of weird...Shouldn't be cold, even missing a cyl or two... I wonder if it might have a stuck heat valve...Ya know, the butterfly looking things at the exhaust manifold/pipe connection.. But even with that, it shouldn't be "cold", being as it's not a total block..Sort of makes me wonder of the pipe is cut off, and maybe let the exhaust temps go super high on that side...Might burn exhaust valves....That would explain a loss of compression... But, just a theory...Sounds weird, thats for sure... Could be a blown gasket though I suppose... As far as the diesel...I wouldn't do that myself...I'd just fix or replace the 390...If you want diesel, I'd buy a diesel truck... Too much different to try to rig it all together...And myself, I would usually prefer the 390 over the diesel anyway... I have to admit to not being that much of a diesel fan though.. They are great if you pull a heavy load like a 5th wheel RV , or whatever, but I hate the sound of them...Too dang noisy... And I bet the sound proofing in the 73 isn't as good as the newer diesels either..."I have a 73 F-100, so I know what the insulation looks like..." There ain't much of it... :/ And the 390 aint exactly a slouch when it comes to towing... That 390 may not be as bad as you think, once you get it apart... IE: gasket...Would be a easy fix...Much easier than retrofitting a diesel....:/

MK

The exhaust running cold could be an indication of a rich condition, as in unburned fuel from a dead cylinder on that side. A lean condition will cause it to get very hot.

Spdloader