Alternator question
I have a 73 touring which has an alternator. Was this a standard fitment or were they Dynamo? The reason I ask is that my headlights are totally useless! I have read about the H4? conversion but apparently the grill then doesn't fit properly. I've also read about an alternator upgrade (E21 or E30?) but how do I know if this has been done already & is it a straight swop? I have checked the obvious earth connections & put new bulbs in. Any help would be handy, thanks, Kev.
Hi,
All 2002s had alternators, but the E21 and E30 alternators had a voltage regulator built into it. The stock 02 alternator has the regulator mounted in the nearside inner wing and it's an oblong box with 3 wires attached via a plug to the underside of the regulator.
Some people change to the later style due to parts availabilty and some models have a higher amperage output. This does not effect the brightness of your lights unless the battery is flat or the alternator is not charging.
To get decent headlights, you need to check the condition of the reflector in the headlamp unit as the silvering slowly burns off after a few years. You can buy replacement ones or even get the old ones replated but it is costly.
You can put a higher wattage bulb in and it will make the lights brighter but the problem is that the higher wattage bulbs give off more gas which 'eats' the reflective coating quicker than the standard bulbs.
The later 02's had a different lens that has H4 marked on the outside and a black metal rim that covered the outer edge of the headlamp. This was done to colour code the visible part of the headllamp with the black plastic grill. The lens is a slightly better design than the earlier headlamps.
To convert your headlights to a newer style is very difficult. I have used VW Golf Mk1 lamps and welded the VW base to the 02 headlamp unit, but when you fit the grills back, the lens do not follow the contour of the grill.
The reason why is that the headlamp beam adjustment on the original BMW lamp is done by moving the reflector in the headlamp base unit. When you fit a modern headlamp such as the VW Golf unit, you need to be able to adjust the whole lamp assembly to give you the correct beam postion.
In America, due to their headlamp requirements, the headlamps must be the typical 6 inch units and the lamps are different to the European ones.
I have used the American 02 headlamp holders which bolt straight in to the stock position and then used Bosch/Hella headlamp units with a left hand dip. The lens still does not follow the contours of the grill, but at least I can see in the dark.
This is the area where a lot of confusion is generated about replacement lamps as in America, it is easy to change as they have the base units that accept standard 6 inch lamps allready fitted to their cars as standard.
Your other option is to fit a pair of driving lights to the bumper and that will help alot.
Hope this helps to clear up a lot of miss-information etc.
Cheers,
John.
Date: Sat, 17 Nov 2007 14:46:34 +0000
From: ...
To: ...
Subject: [bmw02] Alternator question
Express yourself instantly with MSN Messenger! MSN Messenger

Another possible way to improve them is to rewire them so that the light switch just operates a relay that then supplies power direct from the battery to the lights. This helped mine, as did fitting higher wattage bulbs, as John suggests. Bigger bulbs can be an MoT failure in some cars but I was told several years ago by an MoT tester that they’re permitted in a 1973 2002. They’ve been in for at least 10 years now and have never been mentioned at MoT time.
Tim
Thanks for the replies guys. As I said, I didn't like the idea of the lights sticking out from the grill, so the H4 conversion is out for me! I must admit though, I pressumed the headlights would have run off a relay anyway, so if they don't, this is the first step. I will also clean up the terminals on the voltage regulator if I can find it. I don't have any problem with battery drain though. Also, as the car is not really used much at night, I will get some uprated bulbs as well, poviding my reflectors are OK, thanks again.
Cheers James. Do you no if anyone has tried to "make" an H4 bulb fit ?
PS I got my twin 40s running at last. The jetting was miles out + they even had a mixture of different size choke tubes - unbelievable how they were ever in a running engine!
James Child <...> said:
Im not sure but would like to know if you find a solution. Its amazing that the person before you went to all the lengths to fit twin carbs etc and did not get them jetted and set up correctly. I must of run like a do when you tried to start it up? Regards James p.s. I have a nice front bumper with no rust etc but with the holes drilled in for spot lights if your interested
I meant I bought the carbs, well the whole head, off a guy who said they came off a good running engine (wondered what he thought a poor running engine was).
Re the bumper, I'm not sure if I like the tourings with spots. I think they look OK on the saloons with lairy colours - like yours & the Golf Yellow but I'm not convinced on the others, particularly the Touring. Cheers anyway.
To John's point about the headlight reflectors, you can see the
before and after on the car I bought recently. The original
reflectors were really bad and would not even pass the road safety test. I bought new ones from Jaymic (thanks again Fay) along with their custom badge/light bar and I fitted driving lights. To install and replace the reflectors it took maybe 40 minutes in total and the badge bar about 15 minutes with no holes drilled into the bumper. These are very easy upgrades that deliver a huge improvement in night driving and overall appearance to the car..
John – thanks for the extensive detail on the headlights. I have printed that as a reference tool.
Regards, Brad

Hi Guys,
Just to clarify a point about headlamp wiring and relays. Cars (68 to 71) with a narrow single row fuse holder did not have a relay for the headlamps form the factory. A lot of these cars where modified later on and had relays fitted. (Look for wires with green/yellow colour coding)
Cars with a double row of fuses, ie; late 71 on had a headlamp relay and it is usually fitted next to the alternator regulator and is about 30mm round with 2 mounting lugs.
If you are concerned about low voltage at the bulbs, switch on your lights (with the engine running) and check with a voltmeter to see how many volts are there. If you are getting around 11 volts plus, your wiring is fine. Anything lower than 10.5v and you have an issue somewhere. Usually the connections on the relay or possibly a poor earth on the headlamps.
Changing the bulb holders to accept other bulbs is an option, but its very fiddly to do and if not done properly, you will get a lot of beam bounce when you drive over bumps in the road as the bulb vibrates.
Cleaning up the alternator regulator contacts will not help your headlamps at all unless you have a charging issue.
When converting your headlamp units to H4 6 inch units, the lens sit further back in the front panel and do not protrude outside the headlamp grill opening. There will be a gap of 20/25mm towards the car centre line and 10/15mm on the outside edge.
Cheers,
John.
Date: Sun, 18 Nov 2007 00:21:20 +0000
From: ...
To: ...
Subject: Re: [bmw02] Alternator question
Express yourself instantly with MSN Messenger! MSN Messenger
Is your car running the tii alternator? This is a higher output than a standard 02 alternator, but you have to modify the alternator to fit as the mounting postion is different. Your easiest option is to get an one from an E21 4cyl 320 or 320i or failing that, get one from an early E30 318i.
Cheers,
John
Date: Sun, 18 Nov 2007 13:01:03 +0000
From: ...
To: ...
Subject: Re: [bmw02] Alternator question
Express yourself instantly with MSN Messenger! MSN Messenger








Digg
reddit
Google Bookmarks
Yahoo! My Web
del.icio.us
StumbleUpon
Newsvine
livejournal
Facebook
BlinkList