im fairly new to the volvo community. i also have a 1971 vw beetle. i can repair anything imaginable on that car. but thats a simple little thing. my volvo has me confused.

shortly after i got it the alternator started acting up. some days it would work others it wouldnt. it now is to the point it only works if i either go 65 mph or rev the engine really high at a stand still. once one of those has been done it works and continues to work until i shut the car down.

ive had 2 people look at it and both agreed who ever worked on it was very amature.

id like to avoid making an expensive repair if at all nesacary. let me know what could be the problem and by all means ask me anything you need clarification on. please help lol im tired of having to charge 2 batteries and having to keep on in the trunk just in case it decides to die on me.

 

has anyone looked at the brushes? they are part of the regulator assembly, plastic thing with a power transistor looking thing on the back. 2 screws and it comes off, replacements are about $40.

have you checked the ground? that caused intermittent charging problems on my daughter's 87 240. the clue was, volt meter across battery (with engine running) only showed battery voltage of 12.6V or whatever. volt meter on alternator B+ terminal to engine ground, itto, only shows 12.6V. volt meter from alternator B+ or battery + to ALTERNATOR BODY shows the 14V charging voltage, ah HAH! ground wire *looked* OK til we took it off and realized it was heavily corroded where you couldn't see it.


oh yeah, does the alternator light in the dashboard work? should be lit when you first turn the key on. should go out when the engine starts. if that bulb is blown, or the circuit is open such that the light never comes on, then the alternator D+ (the skinny wire terminal) isn't getting any kickstart voltage, and the alternator can't bootstrap itself. the circuit is really simple.... battery -> ignition key -> alternator light -> D+. When you turn the key on, you should be able to measure +12V (give or take) at the D+ terminal of the alternator relative to ground.

now if ALL that is OK, its possible the alternator itself is bad. there's a diode board inside that can fail. the contact rings that the brushes press against can wear out. rebuilding one of these is probably somewhat beyond garage mechanics, but rebuilt alterantors are inexpensive enough. I would *not* get one from the bigbox auto stores, rather, pay a little more and get a proper factory rebuilt one thats been more than just cleaned and had new brushes slapped on it.

 

the little wire on top that is for the dash light it not hooked up at all currently. i just discovered that tonight. the previous owner claimed everything was all good when i got it lol and i believed him

 

ah. well. before hooking it up, probably be smart to test that its wired properly. key off, it should be 0V relative to engine ground, key on, should be 12V, key on and ground the wire, and the dashboard alt. light should light up. if it passes those tests, by all means, connect it.

or just connect it and see if it works, hahahaha.

btw, afaik, your 1971 VW was *EXACTLY* the same here. my old 66 VW squareback had a generator (6V!), but I'm pretty sure by 71 they were using alternators (which are essentially AC generators).

 

my 71 super was actually a generator. its a 1971 texas yellow vw super beetle with a factory metal sunroom. the regulator under the back seat went bad so i decided it was time to upgrade so i put in a brand new alternator and wired it up. worked great until my valve on piston 3 cracked.

 

ah, maybe it was a little later they switched, then. I remember the bug guys being all suspicious of alternators when I was messing with what my bud called **** slot-cars (mostly in the mid 70s for me, I got rid of my last squareback in 83 or 84 and never looked back).

I highly recommend the Robert Bentley book on Volvo 240's, very through and comprehensive. These are actually very simple and easy to work on cars. The LH2.2 EFI in the 87/88 is about as simple as electronic fuel injection gets, and as long as the fuel pump and wiring are in good order, gives many many years of trouble free service.

 

I don't think vw switched to alternators until somewhere around 75. Interestingly, I cut my teeth on vws as well. I had a 55 bug, 65 bug and a 67 squareback. When it comes to the RWD Volvos, I consider them the modern VW due to its relative simplicity and ease of repair.

 

my main ones were a 68 baja bug, and 2 different '66 squarebacks. oh, and my wife bought a 71 wagon (microbus) converted to a camper. I also owned a 84 rabbit convertible (first new car I ever bought), and a 89 jetta gli 16v (2nd new car).

my first significant Volvo experience is when my wife bought a 87 Volvo 240 new... we still own it, its my daughters car now, has about 400K miles on it. I bought a 89 780 Bertone (v6) new then totalled it 6 months later (and got the 89 jetta above to replace it). my wife got a 93 960 wagon (used), wonderful car, she/we drove that for years, it was hit by a benz and bent beyond repair, so she got a S90 (also used), nice car but it blew its timing belt and crashed valves, so we got her a camry :-/ I'd liked the 960 so much I started looking for a 940 Turbo wagon (didn't want the I6 expensive-to-maintain motor), had a really hard time finding a decent clean one without a trashed interior, ended up with a 850 turbo that had new seats so the interior was really nice. never totally happy with that car (awesome power, but rough ride and lousy handling). College son needed car, so I found him a 940SE (essentially a 760/960 turbo wagon), and when prepping that for him, fell in love with the RWD all over again, even tho this 940SE was beat to $#@$#. Started looking again for me, found a 92 740T with perfect exterior, well maintained except it was going to need a head gasket, and worn out seats, for really really cheap. bought it, fixed it up, ended up selling the 940SE and giving my son my 855T (better gas mileage on road trips), my daughter (18) has the 240, and I have the 740T, so we're a 3-volvo family (and have had a total of 7?!?).