This is a trial-fit of an early head gasket design for this engine. It was later revised when the Spencer F.D. sent both cylinder heads to the SCE design studio, where Caleb Hunter locked down the final design.

Finding parts for a 1949 Seagrave pumper truck is a daunting task, so when the Spencer, Iowa Fire Department decided it was time for a full restoration on their vintage unit, one item in particular proved troublesome to locate — head gaskets for the engine. And that’s where Ryan Hunter and SCE Gaskets entered the picture.

“During the process it was discovered good gaskets were required so they called us over to have a look. We took on the full project of designing and building the tooling required to get this old beast running again. The engine building and restoration team are a bunch of perfectionists and it’s a good thing they spotted the head gasket problem or it would only have been a short time before there was a failure,” says Hunter.

Building a gasket for a 60-plus-year-old engine can be challenging. SCE required both cylinder heads so each head could be drawn. Then tooling was designed by averaging the core shift between the heads in order to get the gasket as tight as possible without encroaching into any of the 12 combustion chambers.

Making the pattern for the gasket, based on a scan of the original cylinder head.

“The project came to us because the only head gaskets previously available, actually did not fit. The engine builder purchased a set and found the combustion seals hung into the chambers in several places. This happened for two reasons; the gasket maker was sloppy, and core shift in the head castings is crazy since the engine is so old,” Hunter explains.

The Seagrave’s V-12 engine is a flathead configuration, with two spark plugs per cylinder and dual distributors to ensure complete ignition. This particular Seagrave V12 was based upon a Pierce Arrow V12 but was manufactured entirely by the Seagrave Corporation in Columbus, OH.

With a cylinder bank angle of 80 degrees, the Seagrave Model 66 V-12 engine has a 3.500-inch bore, 4.000-inch stroke, displaces 462 cubic inches and develops 185 brake horsepower. The heavy-duty unit boasts forged connecting rods with floating, pressure oiled wrist pins and a drop-forged internally counter-weighted crankshaft which is supported by seven 2.5-inch diameter main bearings. Maximum RPM or “peak speed” is 3500 rpm.

Extra fun facts for the pumper truck buffs out there — this particular Seagrave Model 66 was purchased new in 1949 by the town of Spencer, Iowa, for the then-enormous sum of $18,749, and the unit was delivered with a certification of testing for 12 hours at 2,297-2,559 rpm delivering between 750 gpm at 150 psi and 530 gpm at 256 psi.

Special thanks to the folks in the Spencer F.D. for the assistance in compiling this article.

For more information on SCE’s complete lineup of gaskets and gasket accessories, check out their website.