Excel SE 86 model year alternator

[John]

My 86MY Excel SE was built in 1985, and when having a new battery fitted today the mechanic thought the alternator may be on the way out. It's pushing out 13.5v but he was expecting to see over 14v. I'm looking into getting a replacement, but not sure if the Motorola unit currently fitted is the correct one. SJ Sportcars list two alternators, one for HC engines, one for LC, noted as replacing the original Valeo and Motorola units respectively.

I'm puzzled why mine has a Motorola fitted when it has the HC engine. I have a 1991 handbook that states alternator output of 90 amps, the earlier Motorola is 70 amps.

Was it the case that SE and SA models had the 90 amp, and that came from Valeo? Earlier LC models had a 70 amp Motorola?

I don't want to replace the alternator with a Motorola equivalent if my car should have the later 90 amp job. The car came with aircon.

Any thoughts gratefully received!

Cheers John

[Hawaiis0]

South west lotus also show two alternators.

Their one for the Elite/Eclat/Excel has the LC part number (my parts book has 2 - LC and HC)

The second one they have is is listed as A910E6604R, and is for NA Esprits etc. This part is not listed in my parts list print as the HC one, but is penned as an amendment in the notes I have.

I haven't seen any note for up rated alternator for AC vehicles, but would make sense.

13.5v doesn't seem too bad but is on the lower scale for expectations. Dr Google says:

A good alternator should produce about 13.5 to 14.5 volts with the engine idling. If the voltage reading is low (12.5 volts or less), it indicates a charging problem but does not tell you what's causing it.

Stu

[rbgosling]

The two alternators are not a bolt-in replacement - I know, I accidentally ordered the wrong one once and it didn't fit! Can't remember what the difference is, it was a while ago, and it may be possible it can be "made" to fit if the appropriate brackets are also used.

Since your car is on the cusp of the update, it is also possible that Lotus were still using the earlier alternator when your car was made. If you have access to the Parts List, it might even say on there the engine or chassis number for the swap-over.

Also, I hope the voltage check was made with a proper meter, directly at the alternator itself. On my car there is a voltage drop to the gauges (that I've got bored of trying to diagnose and have just learned to live with!), so the voltmeter on the dash reads low.

[rbgosling]

Hmm, quick check of the online Parts Manual and it just lists different alternators (and associated brackets, fixings etc.) for Standard Engine and HC Engine. Which would seem to imply that all HC engines should have the later kit. It also suggests that those few post-85 cars that weren't HC would still have the earlier alternator - which is a fact I have no idea whether it actually is true in reality, but I would be suspicious of.

Anyway, the later alternator uses a triangular bracket at the front, the earlier one seems not to according to the Parts Manual, so that may be worth checking.

[John]

Thanks for your thoughts Stu and Richard, am beginning to think my car got existing stock and later cars got the HC version. The car has never been a great starter, if mine has the lower output LC unit and it's borderline clapped out, thats double trouble! It's also possible the car had the HC item originally, and someone replaced it later with a LC one - especially as they are cheaper.

I think I may have to invest in one of the new HC items from SJ.

Cheers, John

[John]

I have the HC triangular bracket and nylon adjusting strap, but a Motorola alternator - which SJ's fitment notes suggest is the earlier LC alternator!

That may explain the less than enthusiastic starting - I've always assumed that was normal!

[Zag]

Mounting for the two are different, you can't just put the earlier one on the hc engine. There are alternatives that will fit though with higher output.

viewtopic.php?t=12827

Just re read th original post, I thought an 86my had 70 amp as standard the lc were 45. Maybe the later ones were 90.
13.5v output is about right too.

[John]

Thanks but I've decided to go with a new one from SJ. I spoke to them today and they said a high compression engine should have the Valeo not a Motorola so someone must have replaced the original at some point. Or the factory fitted what they had and decided a few years later to spec a higher output item.

Once fitted I'll report on what difference it makes...if any!

Cheers John

[John]

Fitted the new alternator and now getting more like 14v above idle, also starting better. Wiper has packed up though!