By the end of the 50s, Hall-Scott’s legendary high-torque six cylinder gas engines were barely hanging on, as the heavy-duty trucking industry and buses embraced the superior economics of diesels, especially as turbocharged versions became increasingly available. Fire engines, especially the pumpers, which required maximum horsepower, were the last segment of the market left that continued to buy H-S engines. Their power-to-weight ratio was still unbeatable. That is, until the GMC gas V12 came along, and offered more power for significantly less money, thanks to it being essentially two mass-production GMC V6 engines in one block.
Here’s how it looked:
And it wasn’t just fire truck pumpers; irrigation pumpers also embraced the GMC V12 for the same reasons. H-S soldiered through the sixties (owned by Hercules by then), and built its last engines in 1970.
It’s almost surprising GM didn’t nix the V12 project for the very reason of its’ effect on Hall-Scott, given midcentury GM’s fear of being trustbusted.
Did you check the oil?..Yes, I did…Which one?..
This is 11.5 L in 12 cylinders, if my math is working.
I can’t find the CC post, but wasn’t there also an inline-6 from GM which was about 1L per cylinder in a huge truck?
GMC made a 503 ci (8.2 l) six in the 1950s. GMC also had a 478 ci (7.8 l) version of their V-6 inthe 1960s.
Funny the ad department says: “…without complicated troublesome dual ignition.”
When in fact TwinSix had cobbled together dual distributors that’d make any dual ignition seem like simplicity exemplified.
You’ve got me curious. How were the dual dizzies cobbled together, and what else did they mean by “dual ignition”?
The GMC V-12 had one distributor with 2 6 cylinder caps on it:
https://barnfinds.com/biggest-big-block-1960s-gmc-v12-engine/1960s-gmc-702ci-v12-photo-3/
Two sets of points were under the flat cover on top (the engine in the picture looks like it has been retrofitted with Pertronix electronic ignition), and a cap and rotor for each cylinder bank. As I remember there was a specific procedure for adjusting dwell and timing, and you could get into trouble if it was not followed. Timing on each bank could be adjusted independently.
The GMC V-12 ignition only had one plug per cylinder, so it would be considered ‘single’. Some fire service gasoline engines like the Hall-Scott and Seagrave had dual (2 plugs per cylinder) ignition.
…!
I can’t decide whether to exclaim “Great Kettering’s ghost!” or “Great Rube Goldberg’s ghost”!
“Timing on each bank could be adjusted independently” also means timing on each bank could be misadjusted independently. Dee-yikes.
The GMC ‘Twin-Six’ was a popular apparatus engine. The ad was no doubt accurate, a pumper built on a GMC tilt-cab truck with a V-12 was quite a bit less expensive than a custom-built Hall-Scott powered pumper and offered similar performance. International offered a special version of their 549 gasoline V-8 for fire service that actually had dual ignition, 2 distributors and 2 plugs per cylinder.
It is very true, by 1970 fire departments had ‘discovered’ diesels, Cummins and Detroit had obliged departments with special high horsepower versions of the N and 71 series engines and the large gasoline engine fell from favor. It seems that all the specialized apparatus gas engines like the Hall-Scott, LeRoi, Waukesha, and Seagrave V-12’s were gone after 1970.
The Dartmouth Fire Department (NS), now amalgamated into Halifax Regional Fire and Emergency, used gasoline powered trucks up into the early 90’s. Montreal purchased a pile of Ford C Series pumpers and ladder trucks from Thibault for the 1976 Olympic Games, and we up for purchase after the games ended. Dartmouth ended up buying a few pumpers and a 100ft aerial ladder truck. The “Little Fords”, as they were known, had 534 Cid mills, with a Motorcraft carburetor that flowed like a toilet on them. Backed by a 5 speed transmission, there were quasi-quick, and preferred to the ancient LaFrance and Cincinnati Cab Thibaults that were relegated to “spare” duty. My dad spent countless hours riding the tailbone, and later driving these trucks. He said they’d shoot flames out of their giant side pipes if you have them a shot of throttle to match revs while downshifting, often to the dismay of whomever was following said truck.
The Ford SD big blocks were far simpler, and cheaper than the GMC V6 or V12, and the COE Ford C Series was defiantly a superior and longer living apparatus base.
We had two Ford C9000’s on our dept but with the Ford 636 badged Cat 3208. NA at only 210HP but dependable. I liked both until our Pierce engines with Detroit 6V92 V6’s.Those were a true fire engine.
Very interesting to see this. Yesterday my son gave myself and my grandson a tour of his fire station and truck. It was a 2012 Pierce. I would have liked to see the engine but that would have been quite a chore I assume. I do know it’s loud, so the firefighters riding in back can converse with those in front the back seats are provided with headphones with a boom mike. The rest of the equipment was fascinating. I just had to sit in the driver’s seat. My 8 year old grandson enjoyed the tour almost as much as I did.