Alternator Not Charging Battery

[Bitsyncmaster]

Ah, didn't know that...I'll go 90/10 then.

Yes an anodized coating could insulate the contact point.

[Ron]

Yes an anodized coating could insulate the contact point.

Sorry, I meant that I didn't catch that it was anodized...I must of breezed over that and dismissed it when Josh said grinding wasn't needed (with jumper, I now see). My mistake.
If the battery is connected last, I'll go 99%

[Delorean Industries]

Due to the increased number of owners deciding to implement questionable components with our complete kit offerings a few full proof changes are being made. In the case of this product we are going to start installing the ground strap for the alternator onto the unit with thread locker. This way the strap is already hanging there ready to be hooked up to valve cover upper muffler bracket mounting bolt. We will still caution against running other tensioners and the risk of lined rod ends in the updated instructions. At the end of the day we can only inform owners as much as possible in an attempt to avoid situations.

[David T]

Alternators are one of the most returned parts for the vendors. Too often the problem is within the car itself but the customer blames the alternator. Between that and not installing it properly, alternators have a high return rate. Many owners do not take the time to diagnose and troubleshoot the electrical system and instead go right for the alternator. While in many cases the alternator may actually be bad, something in the car caused it to fail and then kills the replacement.

[dmcman73]

I went over this with the OP on facebook helping him trouble shoot it down to the heim joint tensioners having teflon inserts on the heim joints themselves creating an insulation to ground.

Now, the kit that DPI sells has a solid metal tensioner bracket which completes a very good ground to the block, very much as Matt's improved tensioner does. DPI isn't at fault for this issue, they do not have control over what owners will do in modifying their full kit offering. Also, if you ever remove the original cast bracket from the engine, you'll find a TON of rust between it and the block making a very unreliable ground connection (Dave Swingle has even suggested on here to remove it and clean it), it isn't a very reliable ground since there are way to many components that can rust and create resistance between the devices, this is a very common issue with a lot of classic cars. If someone who is running the original bracket on their car that had rust between the alternator bracket and block causing a very poor ground then installs the heim joint turnbuckle tensioner, they would probably experience the same issue.

It's not uncommon to see classic cars that were restored to have ground straps coming off the alternator casing. Where the other end ties to (direct to engine block, frame, battery, etc) is debatable. But if it were me, I would tie it off at the frame where the battery cable goes and another from that same point on the frame to the engine block (have you ever looked at the braided ground strap from block to engine mount?).

BTW, I have Matt's stainless tensioner on my car. When I removed the alternator and bracket to install the DPI exhaust and reroute wires, there was a ton of rust between the mounting bracket and block, BUT....my voltage has always been above 13V on my dash even with everything turned on and sitting at idle.

Just my 2 cents.

[Ron]

I went over this with the OP on facebook helping him trouble shoot it down to the heim joint tensioners having teflon inserts on the heim joints themselves creating an insulation to ground.

Now, the kit that DPI sells has a solid metal tensioner bracket which completes a very good ground to the block, very much as Matt's improved tensioner does. DPI isn't at fault for this issue, they do not have control over what owners will do in modifying their full kit offering. Also, if you ever remove the original cast bracket from the engine, you'll find a TON of rust between it and the block making a very unreliable ground connection (Dave Swingle has even suggested on here to remove it and clean it), it isn't a very reliable ground since there are way to many components that can rust and create resistance between the devices, this is a very common issue with a lot of classic cars. If someone who is running the original bracket on their car that had rust between the alternator bracket and block causing a very poor ground then installs the heim joint turnbuckle tensioner, they would probably experience the same issue.

It's not uncommon to see classic cars that were restored to have ground straps coming off the alternator casing. Where the other end ties to (direct to engine block, frame, battery, etc) is debatable. But if it were me, I would tie it off at the frame where the battery cable goes and another from that same point on the frame to the engine block (have you ever looked at the braided ground strap from block to engine mount?).

BTW, I have Matt's stainless tensioner on my car. When I removed the alternator and bracket to install the DPI exhaust and reroute wires, there was a ton of rust between the mounting bracket and block, BUT....my voltage has always been above 13V on my dash even with everything turned on and sitting at idle.

Just my 2 cents.

I'm with you 100% here.
(Yes, that is exactly what I did with the braided straps when I restored 1669...but then it got a stage 2 engine, using the stock configuration...but I expect it will last another 40 years w/o problems ;-)