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Discussion Starter #1
Hi everybody.
Last weekend I was checking power panel trying to get the auxiliary heater going.
It didn't happen, but that's another issue.
Since then I've been having electrical problems.
The batteries were getting drained pretty quick, and starting was rather hard.
I decided to replace alternator, as the batteries (3 of them) are 7 months old.
With the new upgraded one (200A) when I start the engine, with everything off, I'm getting readings of 14.4V, but when I turn the cab vent blower all the way up,
I'm getting only 12.5V. I don't remember getting that low with older alternator.
Also starting the engine is still pretty hard. Starter is only 1 year old.
Any ideas? Am I having ground issues maybe?
 

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I came across this Caution notice tonight while looking through the Australian Miltary handbook for their U1700's.

I don't recall seeing this notice anywhere previously....Totally different type of UNIMOG, but maybe a heavy current draw on the High setting is something they have in common ?


2605364
 

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Good find Tructor !
Yarr, not all alternators are created equally - I remember when plowing through the Bosch alternator manual for my replacement, there were a few few graphs on the universal ones - some are clearly made to operate better at low RPM compared to others. So your situation may well be "normal" given the new alternator.
 

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Thanks for both of you, gentlemen, for putting some input into the case, which, eventually, set me in the right direction.
First, I questioned the compatibility of the alternator itself.
I went with Dixie 101-28103, 12V 200A. Why ?
EPC told me that original was Leece-Neville 12V 270A, then I found the label on my old one saying:12V 160A also L-N.
As my truck has originally 12k hours, but newly rebuilt engine (as some of you may remember), so I figured out, that 160A alternator was replacement from the original.
Assuming 5,000 plus hours for life span of alternator, I concluded, that the second one was dying, and realized that 160A after all would be sufficient for my needs.
I was looking at Delco Remy 8600310 160A, then I found out that there was 8600312 upgraded, but the same amperage, and 8600313, upgraded with 200A.
I've made bunch of the calls, but couldn't find anything locally.
Next day I went to another shop on my list, looking for Delco 8600312 (160A). They said, they could get me Dixie 200A, which turned out to be equivalent to Delco 8600313 200A.
What is Dixie, I asked - sounds like cartoon character, I thought.
Turned out to be Canadian company. OK, let's support local economy then.
Anyway, after Krietpiel questioned alternator compatibility I decided to take the truck to the shop and test the device itself. They said, they would also perform some trouble shooting
on electrical system. That evening they called me, to advise me on conditions of battery to starter cables, that were very brittle and and suggested replacement.
They got my permission.
After that they did some more testing.
The alternator turned out to be OK, and as Truktor discovered, even in UGN the blower puts serious current load on the system,
so the voltage drop made more sense.
With maximum setting on the blower, and headlights on while engine's idling I'm getting now at least 13.2V. No load 14.6V.
Engine starts waaay faster too - just as it should.
 

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The “heavy duty” 270a Leece Neville has an unreliable un replaceable divorced rectifier.
I replaced mine after 2-3 rectifier failures with a 240a clone of the 28si Delco type that you have .
After 20000 mi/600hr it’s been good. For a spare I have a genuine Delco 200A.
I recommend in general to run the fan of the heater/AC on low or medium. Evidently MB screwed up a bit on the gauge of the wire and it can overheat on high with unpleasant consequences. I think the situation is exacerbated with using the Webasto at the same time.
So I generally use low or medium.
 
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