Checking my 720's Alternator at the Source

[gone2long]

Truck is a 1979.5, 720 with a recently repaired (1 1/2 years prior)  alternator.   Used a digital multimeter to do some checks on my alternator output at the battery and got conflicting readings on different days, so I would like to check the alternator output at the alternator.

 

Can anyone tell me an easy way to do that?  Found something on the internet about that, but would like to hear from you folks.

 

Thanks,

 

G2L

[banzai510(hainz)]

make sure the battery cables are good and connections clean. also the fuse is clean.

I get vsrios reading on my alternator sometimes if warm or cold . or if I have the heater fan on right away.

best is to start truck and let warm up before putting lights and fan or wipers on so it chrges back up a little. Could be a volt reg issue in the alternator

[gone2long]

22 hours ago, banzai510(hainz) said:

make sure the battery cables are good and connections clean. also the fuse is clean.

I get vsrios reading on my alternator sometimes if warm or cold . or if I have the heater fan on right away.

best is to start truck and let warm up before putting lights and fan or wipers on so it chrges back up a little. Could be a volt reg issue in the alternator

Yeah, thought about the regulator as a possible problem, but did another test today, and it seems like the diodes are shot.  See my new post "27 Volts AC Current Across the Battery Terminals ..." for details.

 

Thanks,

 

G2L

[gone2long]

Wanted to "bench check" the alternator, but looked all over town and couldn't find anyone who could do it.