Dave: why would you remove the regulator's ability to de-rate your alts when they go over 90C? High temps are alt killers and most are not rated to operate continuously at much over 105C as I understand it. I've got a 6BTA5.9 370 (M3) with same belt wrap you now have. Port side I have a Bosch 120A: notorious for being heat-sensitive, my reg begins de-rating when it approaches 70C. Stbd I've got a Leece Neville 160A large-frame. I've got that programmed to de-rate over 90C, though in practice I've not seen it go past 68C. Both governed by Balmar MC-614 regs + Centerfielder II
Alternator belt slip
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fryedaze
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Good question, I have exchanged emails with the alternator maker and the Sterling regulator folks. The alternator manufacture said that the alts could run at 250+ F. The Sterling guys said just remove it. So I did a test. At about 95 amps without the temp sensor connected the alternator reached 340F on the hottest spot. Needless to say I shut the engine down and restored the sensor. One issue is the mounts for the alternator are 175F with the engine at temperature. The aluminum billet alternators quickly pick up that heat. With a 194F limit there is no margin. I am still trying to resolve this issue. I have got to find a solution that lets me use the capability of these larger alternators.
With the temp protection installed and running at high load (80-95amps)the alternator only run 3-6 minutes and then they shut down and cool off for 10 minutes before they restart. One more suck ass part of this is that my tachs also turn off when the high temp is reached.
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fryedaze
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Quality Power Mega amp alternator. Mega Amp GM High Output Alternator
Sterling ProReg D advanced regulator
Advanced Alternator Regulator
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Hi
An idea to lower the heat transfer from the mounting point. Use Delrin or Teflon washers on both ends of alt mounting Thru bolt, plus a Delrin sleeve around a slightly undersized stainless bolt. That should cut the heat flow from the engine. I am thinking Delrin or Teflon is a plastic with crappy heat transfer that can tolerate 250. What say the experts?
Dan
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fryedaze
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Wow!
This is what the alternator maker sent me today.
"We normally see between 270 and 330* at the stator core when charging at 90-300A.
About 250* is normal if the engine is a about 180* (+) and that is on a 200A alt. the higher amp the high heat. If heat is an issue then you can run a cooling hose to the alt almost like a engine bay blower. Outside air would be the best as it is alot cooler on the water. Cooler the better."
This is what the alternator maker sent me today.
"We normally see between 270 and 330* at the stator core when charging at 90-300A.
About 250* is normal if the engine is a about 180* (+) and that is on a 200A alt. the higher amp the high heat. If heat is an issue then you can run a cooling hose to the alt almost like a engine bay blower. Outside air would be the best as it is alot cooler on the water. Cooler the better."
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fryedaze
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The alternator guys said this.
"Actually the best place is at the rear where the rectifier is. Keeping the diodes and stator cool is the key. Do not put an external fan on the front. a cooling duct would be ok."
Dave: what about changing the alternator fan? First, is it actually set up to blow the right way, which is air moving from back to front? Second, some alts can take different fan types: an alternator rebuild shop can tell you if a higher airflow fan is available that can be fitted to your alt. The following is an extract from Steve d' Antonio's blog earlier this month: "....check the installation to make sure they are equipped with the correct fans (there are bi-directional, straight fin, and mono-directional, slanted fin, fans, if the latter, and the incorrect rotation, they can lead to overheating). Most engines are counterclockwise rotation (when viewed from the flywheel end), which means the pulleys on the front turn clockwise, as do the alternator fans. If the fans are the mono-directional, slanted variety the fans should be turning with the scoop side away from the direction of rotation. Counterclockwise alternator fans are rare, they are designed for clockwise rotation gasoline engines, however, and there are thousands of them out there, so this is a possibility that should be eliminated. Fans should draw air through the back and then center of the alternator and expel it out the front." You just changed the belt arrangement....did the fan direction change too??
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Hi Dave,
Another thing you may try is to delete the belt guard.
When I did the re-route thing, rather than fabing a new guard, I just kept it off.
Things seem to run cooler without it.
In my case, the belt guard is not really necessary, as access to the front of the engine while running is an unusual scenario.
good luck - And Yes cool alternators are happy alternators.
Another thing you may try is to delete the belt guard.
When I did the re-route thing, rather than fabing a new guard, I just kept it off.
Things seem to run cooler without it.
In my case, the belt guard is not really necessary, as access to the front of the engine while running is an unusual scenario.
good luck - And Yes cool alternators are happy alternators.
bshanafelt: Dave's photo at post #29 shows he's already opened up his belt guard considerably...I don't think there's anything more to be gained there. And no belt guard is really not a good idea for most installations IMHO--accidents do happen
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