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4-51

13K views 26 replies 15 participants last post by  FLH Oliver 
#1 ·
Has anyone played with one of these. I have read up on the differences between the 53 series motor. Sounds like a different head with the CC in the head and different liners as it was purely a scavenged motor. So why exactly were the blowers flocked with felt? There is one for sale near that just needs the blower flocked. I know from what I have read that parts are non-existant but I was just day dreaming of a future project beyond my current projects of a 4-51 turbo'd in a pickup. I did read of a guy who had a turbo 4-51 in a truck and it ran like a beast so they say.
 
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#2 ·
I'd like to hear more about the 4-51's as well. A guy in my town flagged me down to talk about my truck. He has a late 50's GM pickup with a 4-51 that he claims was factory installed as a test mule. I've never seen it but he assures me its a 51 series. neat engines.
 
#3 ·
GM definitely fit their 4-51 into a number of medium duty trucks for testing. I have had this ad on my computer for some time showing a 4-51 in a Smith Cement Truck. I have seen a couple 4-51's, an industrial power unit, a generator engine, and two marine engines. None in working order. They share 0 parts with the 53 other than miscellaneous hardware (nuts/bolts). Timothy said that only one bearing interchanges with the 71, and that is the water pump bushing. That is it, everything else is purely designed for the 51 and nothing else. The folks online who say that they use a 53 series piston and liner are full of it. 51's are loop scavenged and the pistons and liners look wildly different from anything a 53/71/92/110/149 uses. I know of a man who had put a 4-51 in a Hudson pickup truck in the early 1960's and said that it was a blast to drive. He had told me that he fit a McCulloch belt driven supercharger to his 4-51 for additional power, but the engine did not like any boost levels at all. I havent talked to him in a while, but I believe that it is a 51 and not a 53 because of the year he put the engine into his pickup.



Chris
 
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#4 ·
When ever anyone tells how great these engines were, I have to ask why they weren't successful. If you want to put one together to watch it run, cool, but if you want a proven engine that you can get parts for in your pick-up, find a 53 series.
 
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#6 · (Edited)
It's currently with a price tag of 4k so I will have to pass considering I can't even hear it run as the blower is taken apart. 4k will surely be used on other projects at this time...if it was half that it might be a different story. There are a few videos on YouTube if you haven't heard one also videos of the 2-51.
 
#9 ·
My 1954 Series 51 bulletin shows a marine engine outputting 87 shaft hp @ 3000rpm with a "marinized" weight of 1300lbs (I am not sure if that includes the transmission as it is also imaged)

If this is the mostly rebuilt 4-51 that is for sale in Washington, $4000 might be a decent buy. I think the owner said that it had all new pistons/liners/and injectors. If you or others are interested, I have the contact of a man in Wisconsin who has rebuilt and made parts for the obsolete 51 injector. Last I talked to him, when I was inquiring on a 4-51 genset, it was basically a $500 down per injector job, if he could fix it. Pricey, but 51 parts are not readily available.

Chris
 
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#22 ·
My 1954 Series 51 bulletin shows a marine engine outputting 87 shaft hp @ 3000rpm with a "marinized" weight of 1300lbs (I am not sure if that includes the transmission as it is also imaged)

If this is the mostly rebuilt 4-51 that is for sale in Washington, $4000 might be a decent buy. I think the owner said that it had all new pistons/liners/and injectors. If you or others are interested, I have the contact of a man in Wisconsin who has rebuilt and made parts for the obsolete 51 injector. Last I talked to him, when I was inquiring on a 4-51 genset, it was basically a $500 down per injector job, if he could fix it. Pricey, but 51 parts are not readily available.

Chris
I have a 4-51 in a 19' steel tug boat. I would love to get the contact info for rebuilding the injectors if you have it. Thank you
 
#12 ·
Knowing what I know now, I kick myself. About 7 years ago i was cutting wood on some crazy hoarder hillbilly's land in Lima and I'm 99.9% sure there was/maybe still is a 4-51 sitting in his woods. Place was literally the set of a horror movie - couple old Lima cranes, old White trucks, a few 80s diesel escorts with trees growing out of them, airplane frames, schools buses from the 60's, you name it it was out there. I remember coming across a big 4 cylinder with remnants of DD green on it, cut back the brush and took the airplane cowl off of it. I distinctly remember the exhaust manifold coming out of the block and not the head, thought "wtf, that's odd....". Never thought much about it until I learned about them years later after I'd already moved back to michigan
 
#13 ·
It's an ok deal IF the work that has been done has paperwork to back it up. Still a non runner at 4k kind of kills it. I like finding deals not paying gobs for a hunk of Iron. Good thing I am currently busy paying for my wedding that has cost me a fortune right now so the extra funds are tight. If it's not gone in a few months (it likely will be with it already being watched) then I may take a second thought about it. I have know about the 51 series for just a little while would make a cool adittion to the lineup. Also read about a guy up here in Wa that put a 4-51 in a 53 Ford and ran it for seven years. Said it was noisy , Smokey, and low on power but was easy on fuel and sounded good out the dual stacks.
 
#18 ·
I have spoken to that guy a few times and he seem a fair guy and knows his stuff.

His prices might seem high, but when you know what you have got, you know what price then can command. most of the time you can buy cheap (basicly scrap) because they don't know what they have
 
#25 ·
I have a 4-51 that I am going through before I start it. The bottom of the blower housing is missing most of the flocking. I have heard that there is a company on the west coast that reflocks them but haven’t been able to find out anymore than that. Does anyone hear have contact information for this place? Thanks
 
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