Would anyone know where I could get hold of an 80mm alternator pully to slow the alternator to a sensible rmp???
Got one of those on my motor and it has not helped very much. Mostly heat related for me, so without cooling they have still died, even went from the ultra light tiny alternator to a slightly bigger one to no avail. In the process of re wiring the whole car so there might be something else that is a problem on my car, will post up if we find anything as it is on the list of problems to fix. Going through 3 a year is getting ridiculous.
Not sure where the pulley came from though, possibly QED or scholar, sure scholar might be able to help.
Did you fit a larger pully as well?
Did you fit a larger pully as well?
Yes it came with a larger pulley and I thought my troubles were over.
My Exige has had original alternator for 5yrs but is an A/C car.Could it be that the higher alternator mount keeps it cool enough to survive?
No! Mine failed at 6000 miles…
No mine failed at 28K miles and again at 32K miles and …
I think three factors
- Sh!t quality of OEM product
- Too hot an area regardless of air con or not
- Vibration … I replaced numerous brackets and lost bolts and concluded that the alternator must be very well balanced to cope with the speeds etc
It will all be in my book
Hmmm, I’ve never had a problem with mine in 38K miles.
Do you have the cooling duct from the right scoop?
The K engine shakes them to bits. On engines from cars that I’ve converted I’ve had three broken brackets, two broken bolts, one faulty alternator and no end of alternator wires either fried or about to break. All on bog standard engines.
As for revs, Simon, I can’t follow your maths. If 7800 rpm equates to 23000 rpm how does 7000 work to be 16100 ? All the pulleys are the same are they not ?
Bernard
Bernard,
You would have to run to 10,000 RPM based on those maths to get to 23000RPM, maybe the RPM was measured in Microns… I make it 17,940RPM.
Oversized alternator pulleys and smaller crank pulleys are commonplace on higher revving engines, I have 4 of them in the workshop at the moment with smaller pulleys. I first used one around 1972 on a mini engine that revved to 9000.
Many of the higher revving K’s I put together have smaller diameter crank pulleys and some have larger alternator pulleys. The problem in the Elise/Exige isn’t confined to overspinning, heat and vibration play a large part too.
Dave
No mine failed at 28K miles and again at 32K miles and …
I think three factors
- Sh!t quality of OEM product
- Too hot an area regardless of air con or not
- Vibration … I replaced numerous brackets and lost bolts and concluded that the alternator must be very well balanced to cope with the speeds etc
It will all be in my book
Cough … like I said
You’ll have to wait for the book.
Dave
Simon,
Lighten up. I dont think that badly machined blocks are acceptable, but my own experiences and measurements have not shown this up. If they had then I would have taken it up with Scholar.
The ‘Micron’ debacle was more about the way that you described the block as 8-9 thou out of round which was plainly and demonstrably wrong.
You are very free at criticising others often with erroneous data but when a rib tickler comes your way that was meant in fun and is bang to rights you do the primadonna bit.
Continual sniping and mudslinging is not a productive way to behave and from what I have seen you need to put your own house in order before levying criticism at others.
Dave
So you have done the resonant frequency analysis, designed new pulleys and specced and fitted them to ALL engines you see - hum taking your engine building seriously at last - excellent!
simon
No, I’ve not designed new pulleys etc. I just relied on the manufacturer of the engine to get it right in the first place. Also, I’m not significantly changing the rev range of the engine, just putting a lot more charge in.
To re-iterate, the failures I have seen were on standard 1.8 engines. You must have seen them also.
Bernard