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MG TD TF 1500 - Generator Problem or normal?

I have a 52 TD with an MGA 1600 engine in it...OK it came that way...

For the first time I turned on the headlights with the engine running. Just to see how much current they drew. I had tested them before to see if the work but paid no attention to the Ampmeter. I noticed that no matter how fast the engine was going there was a maximum indication of a discharge (-) reading of about 10 amps towards charging ( as far it would go toward charging). The head lights are 35/55 watt halogen bulbs. Is this all the generator can put out? I also have halogen tail/ brake lamps. (I want to be seen at night)

With the lights off the charging system appears normal, discharge whne starting , and charging until battery is back to snuff again.

David Garrison


David Garrison

David Garrison

Halogen bulbs do put out. I have the originals and high beams just keep the generator alive. Not a discharge but nobodies getting their battery charge in quick order.

For you that's 110 watts if you are running high beams?
Chris Couper

David - You didn't say if the generator is the original TD unit or an MGA unit. The early TD generator (C39PV) is rated at 17 amps, the later one (C39PV2) is rated at 19 amps. With your headlights on high beam, drawing 110 watts, that converts to over 9 amps just for the headlights. Based on this, there is only less than 10 amps left for everything else. Cheers - Dave
David DuBois

David D.
You seem to be very "up" on this subject..(and your advise always right on target). On a TF 1500 ...any recomendations for a little more "robust" of a generator (higher amperage)? I have "expanded" my electrical system a bit as disscused in an earlier thread and am wondering if I might be looking at this option down the road. This assumes that at some point the painter gets my car done so it can be put back together.
David
David Sheward

David S. - The TF has the C39PV2 generator rated at 19 amps (gleaned all of this from the shop manual in the electrical section and the TF info from the Blowers manual), so if you have a lot of additional draw you may want to think about going to an alternator. Even if you could adapt an MGA or MGB generator to the TFs tach drive, you would only gain 3 amps of output, up to a whopping 22 amps. Someone adapted an alternator to work with the T series cars, complete with the tach drive. It might have been Phil Marino, but I don't really remember. The information on it should be in the archives.
Good luck - Dave
David DuBois

Dave D., Dave S., and Dave G.:

Mike Ash of NAMGAR says the MGA generator is rated at 18 amps. The MGA generator is also a model C39PV2, so I don't think it would be any more thatn 19 amps. You would have to go to a C40 (bigger in size) to get the 22 amps. Many MGA owners belonging to NAMGAR have fitted Lucas two wire alternators. However, the generator doesn't drive the tach in the MGA. The tach drive comes off a skew gear from the cam.

Blake
Blake J.

A useless piece of information, I had a new bearing fitted to my TD generator(c39pv2) this morning and the auto electrician bench tested the genny afterwards, had an output of 50 amps, of course this could not be sustained and would depend on the regulator.
Gordon Wright

Well...After some review of the options:

Leave it as it is; and don't drive, more than around the block, at night..

Or put in an alternator...

I decided that an alternator was in order. If everyone remembersthe car in question is a 1952 TDA (TD with a 1600 MGA engine and drive train). So it was not a question of it becoming "not original". Thanks to the internet I did a lot of research on replacing generators with alternators. I was pleased that I was not to be the first.
The TDA had the 1600 engine placed to the right so the exhaust manafold cleared the steering gear. This made it a tight squeeze for the exisiting generator. It had already been rubbing against the engine side cover. I had thoughts that some day I would make a tear drop bubble (like there is on the left side) so it would have the required room. I was resigned,because of the size of alternators, that I would have to do this as part of the conversion. I found a thread in the archives of this forum concering a Suzuki Samurai Alternator, with an internal regulator, some one had planned to put in a TD. The fellow liked it because it was SMALL. I found one, on the internet of course, ordered it and just finished the installation, and it WORKS! Even at idle with all the lights on there is no discharge! A small amount of metal removal on the mounting bracket and moving the adjustment arm was all that was required to get it installed. It fits just within the envelope and no bubble is required.
The original voltage regulator is still there , but it is bypassed and now only serves as a fuse block and wire connecting device.

If anyone is interestd I will post pictures on a website that I own (non-automotive).

Thanks to all for the input and pointing me in the right direction
David Garrison
David Garrison

David,

Which pulley did you use on this?

Can you post location of the pictures
Jack

Gordon - I hope that you insisted that said electrition will replace your generator if it developes problems as a result of being grossly overloaded. I think that I would also look for someone else to work on my electrical items, someone who would be a bit more careful about their setup befor applying power. A look at the wire size in the TD generator will convience anyone that 50 amps should not be drawn from it for any longer than a second or so. Good luck - Dave
David DuBois

Pictures and details are now posted at;

http://www.rcshowcase.com/mgtda.htm

David Garrison

David Garrison

This thread was discussed between 18/06/2002 and 06/07/2002

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.