HOT Alternator!

[Stoker0560]

well after doing alot of diagnosing i came to the conclusion that i needed a new alternator, although i just replaced it two weeks ago with a junk china made turd alternator, bought a motorcraft reman 140A.. only concern now.. ITS WAY HOT!! after only 5 min of idle the alt got extremely hot to touch.. got a thremo on it..was about 110 degrees at case and 160 degrees inside..after the drive home that case got to about 130 and the internals were about 189 or so.. IMO thats way too hot! in defense i checked my buddies 140A on his Dmax and his after about 45 seconds of running was about 145 degees inside..

i was fairly certain i bought a bad alt but now im wondering if my truck isnt burning them up.. where to start?

[smokersteve]

I have never been able to touch mine while it is running, I thought it was normal

[The Captain]

Mine usually has sparks and flames shooting out of it, so I wouldn't be to concerned about a little heat...

[DieselDano]

I wouldnt be worried. When I am trying to start a truck with almost dead batteries, but it does start, the alternator gets really hot really fast, assuming the alternator is working really hard to charge the batteries back up. The engine can be still cold to the touch, but the alternator will be HOT!

[Stoker0560]

well i went out tonight to push snow..had my lazer thermo gizmo with me..after about 30min of pushing snow i popped the hood to check on it..256 degrees shining the thermo inside..about 150 at the case..this is probly normal and ive just never noticed it before.. but 256 degrees is HOT!

[mrnecsteve]

Just as two batteries are capable of putting out a lot of power....they also require a lot of power to recharge and are operating at full power for a few hours when the batts are low .
This country is FULL of chinese made garbage ......

[Rubenk]

Maybe you have bad batteries and the alternator is trying to charge them up?

[famousamos0901]

might want to check for a short also.

[Stoker0560]

update:.. checked every major wire under the hood for a short..checked connections, fuses, looked for anything out of the ordinary..nothing! so i said screw it and went back out to plow.. figured if it toasted itself i would warranty it out anyways.. so after about an hour of plowing i checked temp..was around 250 degrees...i continued on for another 4 hrs with no problems, although it remained hot.. plow never struggled no batt light everything was fine!

once we finished up out there another guy pulled up to me with an 05 6.0 same truck pretty much, so i figured it would be a good comparison to see how hot his was after plowing.. sure enough..his read 260 degrees, same 140A alt..( different brand i think)

so my conclusing is either both of our alternators are junk. or high heat under extreme conditions is just normal!! he said hes been plowing on that alt for 3 years so.. i guess that junk china turd alternator i had just couldnt hold up.. so everythings good!!

Thanks for all the replies!

[alwil]

I would not worry about it, if it gets too hot the bearings will tell you