Summer Project - cooling system rebuild

Tikvah · May 01, 2014, 06:22:19 AM

Lin, I fully agree with you. I would still love to find some analog lighted dash clocks, but maybe 4" or more. Rare, and expensive. I'm not usually interested in absolute accuracy, even with speed. But knowing if the temp is 185 or 190 makes a difference.

DMoedave · May 01, 2014, 08:16:58 PM

Jim and Wendy upgraded their cooling system recently and described the work pretty well in their blog and I believe on the BusNut sight. mightybus@wordpress or ask your question on busnut maybe he will help.

86102A3 · May 10, 2014, 07:40:10 AM

Dave,
I would recommend looking on the inside lower corners of your radiators for corrosion of the fins. My 102A3 has corrosion on the radiators there. I will be pulling them and getting them re-cored before taking any significant trip. The fins provide support for the tubes and once they start to corrode you risk blowing out your tubes. I think most folks know that heat is a very big enemy of a detroit. That's just my 2-cents.
I know many folks talk about a mist system, since I have fixed my OTR a/c I plan on putting in an emergency over ride that will allow me to force on the heater core while the a/c is running. In theory I will be able to use my a/c system to discharge some of the heat rapidly. It may start to get a bit uncomfortable inside but better than overheating the engine. Just some of my thoughts.

gumpy · May 10, 2014, 04:25:17 PM

I just saw this thread. You've probably seen my page on this, but if not, FYI...

http://www.gumpydog.com/Bus/MC9_WIP/Mechanical/Radiators_And_Blowers/radiators_and_blowers.htm

belfert · May 10, 2014, 05:18:25 PM

Quote from: 86102A3 on May 10, 2014, 07:40:10 AM
I know many folks talk about a mist system, since I have fixed my OTR a/c I plan on putting in an emergency over ride that will allow me to force on the heater core while the a/c is running. In theory I will be able to use my a/c system to discharge some of the heat rapidly. It may start to get a bit uncomfortable inside but better than overheating the engine. Just some of my thoughts.

Wouldn't running the A/C be the last thing you want to do if your bus is overheating? Wouldn't the compressor put extra load on the system?

For cars they tell you to turn off the A/C if you start overheating, but that may be more due to the condenser and radiator being stacked next to each other.

RickB · May 12, 2014, 05:25:50 AM

Having done what you're considering, I would do the seals around the radiators first. If that doesn't fix it just do the radiators. Pulling that squirrel cage assembly is a nightmare and getting back in is just as hard. Doing the seals will probably fix it all.

Rick

Debo · May 12, 2014, 07:46:07 AM

Just as a data point, I've been looking into one of these digital temperature sensor/alarms to put a little finer detail on my temperature management. There's a "marine" model with two sensors - port and starboard that I would use for the left and right sides of my 8V-71 natural. It has a thermocouple that bolts to the block (or head, or wherever you want to measure) and has adjustable alarms for each sensor. I like the idea of having a hard number to make a decision with regarding temps. Here's a link to their site. I'm not selling them and have no connection. Just thought other bus folks might appreciate this.

http://enginewatchdog.com/tm4.html

RJ · May 12, 2014, 08:12:43 AM

Treeplanter (NAME??) -

Up until the D/E Series, MCI's had squirrel cage blowers, not radiator fans like your GMC. The D-Series have dual, belt-driven fans, E-Series and later have systems similar to Prevost & Eagle - large side radiator with a big fan.

Brian -

The standard advice for turning off your A/C when your car starts overheating is because the condenser sits in front of the radiator, thus dumping additional hot air into the engine's cooling system when the A/C is running. This isn't an issue with a coach, as you know, the condenser is not in the engine compartment. The load imposed on the engine by the compressor can easily be handled by slowing down and downshifting - which is probably part of the overheating problem in the first place.

86102A3 (NAME??) -

You don't need to install an emergency override to force on the heater core while the OEM A/C is running, it's already there! Simply turn up the cabin thermostat - that's all there is to it! MCI's A/C system runs "full on" when in A/C mode, and the temperature is automatically regulated by adding heat to the cold air coming off the evaporator. Thus turning up the thermostat dumps more heat into the cabin, and now you're using that big old heater core as a supplemental radiator. Of course, slowing down and downshifting to the next lower gear will help tremendously, unless there's a mechanical failure of the cooling system, and that's a whole different ballgame.

Tikvah (NAME??) -

I tend to agree with Clifford and Rick - leave the squirrel cages alone (unless you can find a set of OEM from an MC-9 that came with an 8V92TA) - just clean and lubricate everything well. The welded bracket you're concerned with, if welded properly, is probably stronger than the original. If you do pull anything, just pull the radiators themselves. And if you want to go crazy, replace them with the thicker units that came with the above-mentioned 8V92TA-equipped coaches. As also stated, make sure you seal around the radiators well, so that all the incoming air passes thru them, not around. If you do decide to pull the blower/gearbox assembly, follow Clifford's advice and use a forklift to get it in/out - but if it ain't broke, don't fix it!

Yes, a smaller diameter pulley will increase the air flow, finding one becomes the challenge.

Here's a link to an outfit that has combination digital/analog gauges, which might be exactly what you're looking for. Fast Fred on the BNO BBS mentioned them as his source for new gauges in his Flx:

http://www.glowshiftdirect.com/

Finally, to those of you who I put (NAME??) after your handle, please take a minute to update your forum profile info to at least include your first name in a signature line. It really helps us include you more personally in our crazy little busnut family. Simply click on Profile in the tabs above, then when the next screen pops up, click on Forum Profile Info and follow the prompts. And if you haven't already, adding your home-base city/state plus coach make/model/powertrain also helps us better refer you to local parts & service sources. Thanks!

FWIW & HTH. . .

86102A3 · October 11, 2014, 02:55:24 PM

Thanks RJ,
I am hoping that I will not need that boost once I have the radiators rebuilt. I have not had any overheating issues yet, but I also have not driven up a long grade or through any deserts. Only long trip I have been on was getting the bus home from Alabama to florida.

akroyaleagle · October 12, 2014, 12:58:27 AM

Dave,

Your gauge is marked with the normal operating temp. Probably represents 180-195. Everything I've read says diesels operate most efficiently at 195. Most like the lower temps around 180. It appears yours is functioning as designed.

I too take the position of preventative maintenance is good. My program is a little better than "Call Luke or Clifford". I would however not hesitate to call Clifford if I was stumped or just needed some advice. I also think Emergency Road Service means just that. Not a substitute for poor maintenance.

An old aviation idiom... PPPPPP.... Proper planning prevents piss poor Performance! I don't know about yours, but I think Frankie wouldn't enjoy busin if I was always reacting to problems instead of enjoying ourselves.