Summit Heater for a SIII

[sven]

My S3 never had a functioning heater and after finding out what a stock heater core and fan motor cost, I decided to fit a generic heater. The heater I used is a 28,000 BTU model from summitracing #991102 ($135). Its made by Heatercraft and is made to fit basically anything from RVs, boats, jeeps, buggies, you name it. It comes with a 3 speed motor and 3 row heater core . Also comes with a switch, wiring, and brackets. I thought about installing it inside the cabin, but the space is limited underneath a series3 dash. So I decided to mount it where the factory stuff was and it fits pretty good there. The only modification I had to do was block off the 2nd duct in the heater and weld a bracket to the top of the heater box. I actually used the 2nd duct opening that I cut out and put that where the square hole was on the bulkhead. Then I connected the 2 with 3" flexible HVAC ducting. I wired up the switch to my S3 hazard panel. The airflow comes into the stock location so the vents and defroster work the way they did before.

Before:


The new heater stripped down:



Close up of the new 3 row core:



Installed! I mounted it to the stock holes where the old heater box was. I also bolted it to that side bracket thingy:




I have tested it out yesterday here in Central Pennsylvania for a few hours. It was about 34 degrees and I felt comfortable with the heater on Low. Im also missing a few door seals and I have a softtop! Cant wait for a real test!

[sven]

Another shot:

[stolenheron]

awesome job!

[TerryS]

Thanks for the info Sven. That's a very tidy installation, and it has given me some hope for my exMOD 109. The inside-the-cab heater in MOD trucks is barely a footwarmer.

[XtremeMarine]

Excellent job. Very clean, and professional looking install. Nice fab work.

[CliftonRover]

I think I will have to be getting one of those for my 109 sw. do you think it will heat well enough to warm the second row of seats? One more question, did you have to modify the fender at all? It would be great if it fit in that area without me having to remove the fender too.

[The Colonel]

That did look great. My series heat is working great since i put th radiator muff on. I too have leaky door seals that allows the wind to sneak in and push my accumulated heat out the other door. DOH !! I would consider that system possibly in the future...but so far so good with the muff. (RoversNorth $50 beans)

[sven]

Originally Posted by CliftonRover

I think I will have to be getting one of those for my 109 sw. do you think it will heat well enough to warm the second row of seats? One more question, did you have to modify the fender at all? It would be great if it fit in that area without me having to remove the fender too.

I think it will heat pretty well inside a 109. Mine's a softtop, so Im loosing alot of heat through the rear tailgate (no seals). But the footwells are pretty warm. Im also missing a door seal here and there too.

The fender was untouched, no holes cut either.

[Fred Arvidson]

Just finished a similar project on my 72SIII (bought it new); used a Mojave aux heater with plenum (J.C. Whitney best price) and installed under Driver's seat (LH) puts out around 15-20K btu. Directed vents to floor and FINALLY! after only 35 years in Alaska plowing snow and daily driving I'm "roasty toasty".
Just joined the group so I hope this response is in the spirit of the forum. We bought ours in 1973 and drove up here to Alaska and have been here ever since. I'll try to get some pix when the snow stops.

Fred Arvidson