Bored, been thinking--a dangerous combo

Jim Eh. · July 23, 2019, 12:42:00 PM

If rad size is an issue, have a look at some racing websites that sell aluminum rads. They have some high efficient ones in a small foot print.

richard5933 · July 23, 2019, 01:12:42 PM

The radiator in our Perkins/Kohler 12.5kw generator is discussed in the Custom Coach manual as "basically a Chevrolet core with custom top and bottom tanks". It certainly looks larger than the average generator radiator. The squirrel fan pulls an enormous amount of air through the radiator - in through a hole in the opposite side door and out through a hole in the floor. You don't want to pull air through the floor, unless you're keen on clogging your radiator with grass and dust almost immediately.

Assuming that the genset has been installed in the bus for a long time, my first thought on it overheating would be to check the radiator and see if it needs to be rodded. Generator radiators probably get even less love than our bus radiators, and it wouldn't be surprising to see one clogged internally and in need of a good cleaning.

chessie4905 · July 23, 2019, 01:49:40 PM

And some don't get a work out near their rated capacity till it is close to 100 degrees out and they run all the ac units. Units had received little love till their is an issue. How many check regularly check for tight secure connections on the big wires and cables?

richard5933 · July 23, 2019, 02:17:12 PM

Quote from: chessie4905 on July 23, 2019, 01:49:40 PM
And some don't get a work out near their rated capacity till it is close to 100 degrees out and they run all the ac units. Units had received little love till their is an issue. How many check regularly check for tight secure connections on the big wires and cables?

I was told minimum of 30 minutes run time a month with a substantial load on the generator to ensure that the windings stay dry through the change in seasons. Motor also benefits from the run time, but drying out the generator was explained to be the biggest reason. I try to run ours year round at least a couple of times a month, but in the winter it's a challenge. It's easy to apply a load once started (electric heat) but getting it started when temps go near zero is a chore since we don't have a block heater.

Gary Hatt - Publisher BCM · July 23, 2019, 02:29:34 PM

Have you considered installing a larger radiator like this on your bus Jack? I think this should keep it cool.

Jim Blackwood · July 23, 2019, 02:37:32 PM

Even if you avoid sucking air from under the bus it'd be a good idea to place the inlet low and the outlet high, preferably on opposite sides of the bus, although I realize that raises a noise issue. However, a household furnace filter on the inlet can keep the grass and rocks out, and a larger opening means lower velocity to pick stuff up. If you've augmented the airflow enough though I suppose it makes little difference how you route it, and if the genset is big enough you'll never notice the additional current draw. Sorta like Gary's suggestion. Might eat into your mileage figures though.

Jim

richard5933 · July 23, 2019, 02:43:11 PM

If the radiator is properly sized and the fan is moving enough air with positive flow, it should make no difference whether you're blowing up or down - we're only talking about a few feet of lift here, and the natural convection isn't the concern since there is a fan.

In addition to many generator installs, OTR a/c condensing unit pull in from the side and out through the floor of the bay. Not sure if there is a reason to reinvent things. Just make sure things are up to snuff and carry on.

Jim Blackwood · July 23, 2019, 05:18:41 PM

Small differences add up. You can ignore them but it'll cost you. You've seen the size of those motors on the AC fans, they weren't the least bit concerned with an economical solution. The goal was massive overkill. If that's what you want with your generator system it's easy enough. Fit a massive genset with an oversized radiator and an excessive fan. And don't concern yourself with the cost.

BTW, Summit sells generic aluminum radiators for a very reasonable cost. One for a V8 Camaro runs about $200 which is a pretty good deal.

Jim

oltrunt · July 23, 2019, 06:39:10 PM

Guys, all I have is a little air cooled Yamaha 3000iSEB air cooled genny. I'd need a trailer bigger than my bus to carry all the gear that has been suggested. For me the bottom line is don't up the RH in your genny box---it'll corrode the windings and spoil your fun. I wish I had space for a nice diesel genny etc but that is way out of my league. Still, it's fun to read all the suggestions. Jack

chessie4905 · July 23, 2019, 06:42:22 PM

Just go get one from a salvage yard. 35 bucks and get the electric fan that is attached to it. If you have a you pick it yard, even better. I love walking a salvage yard occasionally. Trip down memory lane and see things that are useful for other ideas.

Glennman · July 23, 2019, 10:02:51 PM

On my '74 MCI, I recently relocated my 13 KW Kubota genset from an enclosed bay (it was mounted in there, but never hooked up... I bought the bus that way), to the screened bay behind the front driver's side tire. I've run the coolant lines to the spare tire compartment where I'll install the radiator and fan. I'm in the middle of this project, but so far it looks good, but it is somewhat of an experiment at this time. I'll let everyone know how it works (or if it works).

richard5933 · July 24, 2019, 03:07:14 AM

Quote from: Glennman on July 23, 2019, 10:02:51 PM
On my '74 MCI, I recently relocated my 13 KW Kubota genset from an enclosed bay (it was mounted in there, but never hooked up... I bought the bus that way), to the screened bay behind the front driver's side tire. I've run the coolant lines to the spare tire compartment where I'll install the radiator and fan. I'm in the middle of this project, but so far it looks good, but it is somewhat of an experiment at this time. I'll let everyone know how it works (or if it works).

How are you routing the airflow for the spare tire compartment?