BritishV8 Forum

I am looking for a very small alternator for the Mini DOHC project. Some 215 V8s have used a Denso and some others have spoke of small tractor alternators. Anyone have any ideas?

-BMC.

Well, there is a very small Denso alternator that was used on Geo Metro's and put out about 30 amps. It's the smallest passenger car alternator I've seen and I used one on my roadster for several years before upgrading to the larger Denso alternator that puts out around 75-100 amps due to adding fuel injection. I have a couple of estate tractors though  and theirs are quite small. I'll try to look at that for you.

Jim

You might also try Jones Racing. They sell a number of mini-alternators starting at about 65 amps weighing only 6 pounds up to a 140 amp version at about 13 pounds. The 65 amp version look tiny.

OK Brian, here's the scoop. The Massey 1233 (which is a 30hp Iseki 3 cylinder diesel) uses the same small Denso alternator. Not a whole lot bigger than your fist:



The Yanmar F17D which is a 21hp 3 cyl. diesel uses a different item, pancake style 2 wire unit, probably quite low output. It is quite a bit larger in diameter than the Denso but also thinner:



Of the two I would pick the Denso every time. It is much easier to find and is very typical in operation. The Yanmar unit might very likely be single phase, similar to many earlier dirt bikes. (as opposed to 3 phase used in most alternators.)

Jim

Wow. Good info. I really like those Jones Racing alternators. So what is the difference between the 1-wire and 2-wire units? One is a ground or something? Or it's automatically switched or something?

On the serpentine belt system: Is the stock Rover main pulley 5-groove? Seems like a good upgrade.

Call the folks at Jones. They know their stuff and are nice to deal with. Prices are competitive for similar products.

I've run a Metro alternator on my '66 for years. I found a rebuilt one at the U Pullit for $10. Had it tested and it puts out 52 amps. The alternator shop sold me a V groove  pulley for $5.