The following request for suggestions comes from an engineering
school dropout and experienced hobbyist mechanic.
I'd like to make an air heater for the intake of a diesel engine
to help with starting in extremely cold weather. Propane will provide
the heat. I have an idea of fabricating something similar in
principle to the familiar Modine heaters that hang from the ceilings
of many light industrial loft spaces. I.e., the burning propane will
go through channels that intersect the air intake, making a heat
exhchanger that won't pull any of the burnt propane into the engine.
The engine's air intake configuration features one section of 3"
O.D. metal pipe about 18" long, clamped to a rubber hose at each
end.
I plan to retire that piece and install, in its place, an
assembly fabricated from standard diesel exhaust piping, adapters and
other cheap parts. I'll use a section of 3.5" exhaust pipe and
connectors that neck down to 3" to connect to the existing hoses.
I'll conserve the existing expensive engine part and can happlily hack
away at those cheap parts in attempting to fabricate a heat exchanger,
without fear of repercussions.
Ideas:
Cut into the 3.5" pipe and weld or braze in some pieces of metal
tubing or something of the sort, to provide channels for the burning
propane and transfer heat to the intake air.
Build an inner chamber where the propane will combust.
If that looks too much like work, maybe just flatten a spot on
the pipe, bolt a heavy aluminum heatsink inside and heat the flat spot
on the pipe with a propane flame from the outside.
I estimate that, even at idle, I'll need to add on the order of 10,000 BTU/hr to the intake air to make this engine feel really, really happy with the block at zero fahrenheit. Sort of a not-very- well-informed guess. 5.9 liter engine. No, I can't use a block heater. I live off the grid.
So the question is, what's the best way for a guy with basic tools to make such a heat exchanger? Angle grinder and a gas welding setup, stuff like that.
I estimate that, even at idle, I'll need to add on the order of 10,000 BTU/hr to the intake air to make this engine feel really, really happy with the block at zero fahrenheit. Sort of a not-very- well-informed guess. 5.9 liter engine. No, I can't use a block heater. I live off the grid.
So the question is, what's the best way for a guy with basic tools to make such a heat exchanger? Angle grinder and a gas welding setup, stuff like that.