Identify my '74 alternator?

[bigchillcar]

Hi again,

Without pulling the alternator out of the car, is there any other way anyone can identify my '74 911's alternator type...if it is the internal or externally regulated version? Any hints will be appreciated. The wrench has the car right now, but may not get a chance to look for a few days at the problem (alternator light won't extinguish/voltmeter across a circuit showing battery voltage while running). I'm just wanting to get a headstart at looking to see what I should be paying for replacement, etc.


Ryan

[schulr]

With the engine running, you should show 14 or so volts at 2000 rpm's, and somewhere around 12 or so when the engine is off. Regulators were made internal after 82 but yours may have been previously changed. If you see the regulator outside of the fan housing, then its external. Post a picture if you are not sure.

[bigchillcar]

Yep,
Wish I could go outside and take a look, but I'm at work and the car's with the wrench anyway. I don't recall seeing a regulator externally, but can you tell me exactly where I should have been looking? As far as the voltage I agree and I would certainly only expect ~ 12 volts (battery voltage) without the car running.

Ryan

[schulr]

actually not sure where they put the regulator prior to 82, suppose it was mounted on fan housing. Wayne's 101 book has a very good article on trouble shooting alternators. From your description, it could be a number of issues. What voltage are you getting while the engine is running? If in the 16 to 17 range, the regulator is overcharging and will need to be repaired.

Good luck, should be $$$

[RoninLB]

Ryan..I up-graded to alternator w/internal reg. and never pulled old external reg. from left side fuse panel area behind black plastic oovering..I carry a spare regulator/cost about $50...............Ron

[McDaniel]

Actually the alternator is not that hard to pull. The wide
metal strap with the allen head bold and the three or so
hex headed screws on the fan shroud are all you need to
loosen. It will pull out without any problem.

[RoninLB]

I'm w/ McD on this one..could be plenty of small nonsense BS inside there you might want to clean up..............Ron

[bigchillcar]

Schulr,

I checked voltage across a circuit running and not-running...voltage didn't change - only ~ 10-11 volts on my meter. This is leading me to believe it's the alternator; it doesn't sound like it's producing a voltage to regulate.

Naturally my wrench's manager at the shop says it's a '3 hour job to take off and put back on' @ $60/hr. So the regulator is located somewhere near those 3 fuses in the left side of the engine compartment then, Ron? I'd have to go back to his shop and take a look then to know for sure if I've got it. I get the feeling this is going to be the 'big repair' for the year. So far I've only paid for a valve adjustment this year. I had a feeling that the alternator could be removed fairly easily, but with no garage and the ex with all my old tools back in Florida, I'm resigned to bending over when the jobs require more time and effort.

I looked at 'Performance Products' magazine over lunch to check prices and need to check Pelican online now. This shop gives you a hard time over trying to buy your own parts.

Ryan

[RoninLB]

Originally posted by RoninLB
Ryan..I up-graded to alternator w/internal reg. and never pulled old external reg. from left side fuse panel area behind black plastic oovering..I carry a spare regulator/cost about $50...............Ron

Ryan..you may still have the external reg installed and an upgrade to internal style..you want an internal reg/no matter there..and a shop doesn't want you to buy your own alternator/ they make some bucks on the part..it's a turn off to the mechanic to supply your own parts......you can use my tools if your on a ride/anytime...hate to hear about your final cost IF you need an alternator............Ron

[bigchillcar]

Ron,

I think I get your meaning now. My alternator may indeed already have been updated to the internally regulated and they may have just left the old ext. regulator where it was...true. Yeah, I know how mechanics are about not wanting 'customer supplied' parts...that was more of a rant I guess. Their concern is the customer not getting what they need, etc. and having to #@! with all of that.

You're the man, Ron...appreciate the offer! Is LB anywhere near Arkansas?

Ryan

[bigchillcar]

Well,
Just called my wrench (these guys are always out of breath and have always 'been swamped'...you'd think they were all in Florida! ) Ha ha...anyway, he hasn't had time to look at it yet, so didn't get a definitive on whether mine is int. or ext. regulated. I did tell him to just troubleshoot it and to call before #$@!#$ing me. I may bring it home (apt.) and try to get the alternator myself if it comes to that. If it's just a reg. I'll be lucky I suppose.

When you get divorced just shy of 40 (37 actually), lose your house, start over with nothing (second time! ) and buy another p-car, you'd better be prepared for trouble I suppose! Sign me a DIY'er out of necessity these days!

Ryan

[McDaniel]

If you can get it out of there you can pull it with just a very
few simple tools. Less than $20 worth at Sears, including the
allen wrench. Then I would take it to a re-build shop and get
them to trouble shoot it. Much less than the 3 hours at $60.
BTW, the '74 came with two different brands of alternator. Off
the top of my head cannot remember...Marschall? Maybe....
If it has to be replaced...sheeesh! Take out a large loan.
Good Luck!

[bigchillcar]

Hi McDaniel

Yep, Marchal, Motorola, Valeo and Bosch...$275 - $575 depending upon which one you want. I like your idea of removing it after they troubleshoot. I'll tow the car home if I have to in order to DIM!

Ryan

[RoninLB]

Valeo is good stuff, IMO...and if you get an alternator, get a spare regulator..and install a voltage gauge to, especially, track an over-voltage problem/which can cause big problems..the "Gen" lite won't come on ........Ron

[bigchillcar]

Hi Ron,

Valeo's the one, huh? I'll keep that in mind...wrench says he'll call first when he finds the problem. He says lots of times it's just the regulator (holding breath). Actually he's a great guy...he maintained the car for the p.o. for over a decade...it's the guy working the cash register that's a PIA.

True enough, without a voltage gauge you just never know. I take it you've installed one on your car - where'd you put it?
Ryan

[RoninLB]

Ryan..I removed the original cassette storage area on the console and made a new plate from old plastic..I used an analog gauge to be able to give a quick glance at the needle, a digital would be difficult for my aged eyeballs to read quickly..the voltmeter is on top, and a dual EGT ga. is on bottom..cheap insurance........Ron

[bigchillcar]

Suhhhhhhh...weeeeeeet! (we can get a little carried away down here in Arkansas)

Mine doesn't have the console, but I can see that sure gives you a convenient place to mount one where it looks oem to most of us non-concours folk.

So I'm driving the girlfriend's land yacht (Ford Expedition) in the meantime! Thanks for your replies, Ron...we '74-'77 guys really need to stick together on the board with this crew, eh?!


Ryan