Radiator in Spare Tire Compartment

Jcparmley · March 04, 2019, 10:33:49 AM

Has anyone ever cut a hole in the front bumper of an MCI and placed a radiator in the spare tire bay. Placing a grate on the bumper and using the "ram air" effect for an extra radiator might provide extra cooling. I was thinking of a folded radiator core like they have on big cat equipment. II saw a pic of a Prevost that had a front grille in the bumper. Here is a pic of the radiator core and of the Prevost I mentioned.

lvmci · March 04, 2019, 04:49:04 PM

Interesting, but the engines 40' away!

Jcparmley · March 04, 2019, 06:44:30 PM

I would assume one would have to use another pump but wouldn't the 40' add to the cooling. You could bypass it with a valve when it's not hot or the terrain is flat. Then open it up when needed.

Iceni John · March 04, 2019, 07:55:55 PM

I briefly thought of doing something similar, by using my front heater/defroster's supply and return pipes for a new front radiator. But (and there's always a but) it wouldn't do tiddly-squat simply because the existing coolant pipes are 3/4", and they won't flow enough coolant to make much difference overall. My 150K BTU combined front and rear heaters will slightly drop coolant temps while climbing long grades in hot weather, but not by more than a few degrees at best.

I completely rebuilt my entire cooling system a few years ago to resolve some ever-worsening overheating issues, and while my temps now are mostly acceptable I still feel that if I were climbing Baker Grade or Cajon Pass in 90-plus degree temps I would still overheat, even while keeping 1900 RPM and 18 PSI boost on a 3/4 throttle in 3rd gear. So what's to do? I'm now giving serious thought to having a second radiator on the right side - a Ford F250/Excursion radiator will fit there, and if I run 1.25" lines to and from it and use a dedicated Groco booster pump just like for my heaters I should be able to lower my temps enough to make a worthwhile difference. Unfortunately I have only a 1" coolant outlet on my driver-side thermostat housing, so that's the bottleneck that may restrict coolant flow too much. Another thing I'm not sure about is the heat rejection rate of the Ford radiator - I've never been able to find that info for any radiators, and I don't know how it can be calculated; even Atlas Radiator in Santa Fe Springs CA couldn't tell me what my brand-new radiator's BTU rating is! I know that a 6V92 at full wellie can put 12K BTU a minute into the coolant, but without knowing the radiator capacity it's just a guessing game for what will or won't work.

John

HB of CJ · March 04, 2019, 09:02:50 PM

Anything may be possible if enough engineering talent and outright money is thrown a a fun cool project. I had dreams of a 120 mph Crown Supercoach ex school bus now ultimate drivers bus conversion motor home. To cool that Pittsburgh Fuel Injection 750 hp Cummins Big Cam Two engine would have required a second front side radiator assembly with all the shortcomings and required ducting, fans, hoses, etc. Not practical. The Crown bus is long gone with the wind. The old dream remains.

chessie4905 · March 05, 2019, 04:31:37 AM

You can change the engine oil cooler over to a radiator type. Is your trans cooler through a separate radiator?

Jcparmley · March 05, 2019, 01:56:25 PM

From what I read I believe the Trans cooler and the engine cooler are the same. Is that correct. My bus is in storage and it's covered in snow so I can't even go and take a look. I was thinking about putting another Trans cooler but if they share the same coolent that wouldn't really help. However, if I completely separate the Trans cooler from the engine system perhaps it would lend to cooler temps in the engine because the Trans isn't dumping hot coolent into the engine system.

Quote from: chessie4905 on March 05, 2019, 04:31:37 AM
You can change the engine oil cooler over to a radiator type. Is your trans cooler through a separate radiator?

chessie4905 · March 05, 2019, 02:25:53 PM

Another thing used by many with heating issues on long hills in summer, is a misting system. It sprays a mist or fine water spray over radiator fins. You don't need a large amount. It is quite effective at dealing with this issue. Relatively inexpensive to make up a system. If you check the archives, there is a lot of posts about making/ using one. My opinion is that anybody with a two cycle Detroit should have one for cheap insurance when you encounter this issue in extreme temps climbing a mountain or long grade. It is not a band-aid however. If you have a bad or partially plugged radiator or missing fan shroud, slipping belts,etc., those things need corrected first.
Course, you can drop injector size to reduce the heat build, but few are willing to sacrifice power.

Iceni John · March 05, 2019, 06:04:16 PM

As part of my cooling system rebuild I added a transmission cooler. Most of the time a lockup transmission runs slightly cooler than the engine coolant, and my tran cooler now dumps a few degrees more heat from the tran fluid before it even reaches the engine's heat exchanger; this should mean that it's actually sucking heat out of the coolant and transferring it to the tran fluid. In cold weather the coolant will quickly warm the tran fluid to prevent problems from driving with fluid that's too cold. Win win. I would like to have another similar cooler for the oil that always runs a few degrees hotter than the coolant, but there's no more space back there for it! (That's why I'm thinking of the second radiator.)

I did add a mister, but realistically I'm not expecting much from it. If it drops coolant temps by a few degrees, great, and if it doesn't, who cares? It uses distilled water to avoid liming the radiator's fins, a separate SHURflo 60PSI pump, and mists the incoming air to knock its temp down slightly. How much difference does it make? The jury's still out on that one. If you live somewhere that's humid in the summer it won't do any good, but in the dry desert SW they can be useful, maybe.

John

chessie4905 · March 06, 2019, 04:10:08 AM

To save on the cost of distilled water, you can collect it from a dehumidifier. Posts on here talked about mister output and effects of different flow rates. Unless it is reposted, just check archives.

Jim Blackwood · March 06, 2019, 09:56:34 AM

I would expect it to help significantly, it takes a great deal of heat energy to vaporize water, which is what you are doing with the spray mist.

Rain water should also be acceptable as it is naturally distilled, though in some areas it can pick up things on the way down.

Jim

RJ · March 06, 2019, 04:19:49 PM

JC -

Hiding behind that front bumper on the Vantare Prevost is not another radiator, but most likely two compressor/condenser units for the mini-split AC system. At least, that's how my Vantare is set up.

FWIW & HTH. . .

lvmci · March 06, 2019, 05:49:27 PM

I took Tom C's advice and drilled my home Depot misting system with 1/16th drill bit. Increased cooling substantially, lvmci...

Jcparmley · March 06, 2019, 06:26:51 PM

RJ do you have any pic of that set up? That would be interesting to see. Thanks

Quote from: RJ on March 06, 2019, 04:19:49 PM
JC -

Hiding behind that front bumper on the Vantare Prevost is not another radiator, but most likely two compressor/condenser units for the mini-split AC system. At least, that's how my Vantare is set up.

FWIW & HTH. . .