We currently have 450 of these buses. the last 2 year models 01-02 run hot. After t-stat changes and washing radiators we still have the problem. IHC says trans to hot. Allision says Ihc air flow problem . Can any one help here+
You don't mention the engine your buses have. Are your pre-01 buses equipped the same way? What is different?
I have seen very few IHC engines run warm, let alone hot. I would suspect one or several causes. The first would be too small of an engine. The DT466 is a great engine in the RE. The 444TE is not quite enough.
The second would be a continuation of the first problem--if someone really went cheap and got the small transmission with the small engine you could have a real problem keeping things cool.
We got some early 1990 BB TC2000 72-pax buses that had some overheating problems. They came with the small engine with the small transmission with the small trans cooler. Any hill or temps in excess of 65 degrees saw the buses overheating. The problem was solved with a mega sized trans cooler, although they still have problems with running too cold when they aren't working hard and really heating up on long grades.
It may just be a simple problem of the trans cooler not being sized correctly or a fan clutch not engaging soon enough.
Can you install a tempurature gauge temporarily in the trans oil line somewhere to check the oil temp? When they are hot use an infrared thermometer on various heat sources to locate high temps. Brad
Ive had problems with the DT466E's nand DT466's running hot(in 3800 conventionals) in the warmer times of the year when the heater valves are turned off. I changed to a lower degree viscous fan drive and it took care of the problem. Awhile back I posted the same compliant and I belive a Navistar rep. suggested converting to an on/off lock up fan drive. One item I noticed on some older units with DT360 engines with side by side radiator/cac that the foam used to block the uneven areas where the cac fits into the radiator were missing and allowing the cool air to bypass going through the cores. I would recomend if you replace a radiator to make sure the openings are filled. Peace, Joe
quote: We currently have 450 of these buses. the last 2 year models 01-02 run hot. After t-stat changes and washing radiators we still have the problem. IHC says trans to hot. Allision says Ihc air flow problem . Can any one help here+
We have eight of these -- all with the "fantastic" new electric fan clutch that IHC pushed when these were purchased. We have replaced two and three fan clutches in some of the units -- many of these have temps that climb upwards of 230 degrees. They're simply not being cooled because the fan clutches are faulty. Get away from the electric fan clutches, if that's what you have because I'd be willing to bet the farm, that is the root of your problem.
Brian
Brian J. Whitta Transportation Supervisor Fostoria Community Schools FOSTORIA_BW@noeca.esu.k12.oh.us
IHC AMTRAN RE
Posted - 12/16/2002 : 4:59:32 PM
