Low Rev alternator

[Val Popescu]

Need a low rev/small size alternator.

[DB4 Tim]

If you find the correct Alt size can you then change the alternator pulley to reduce the RPM or the drive pulley ?

Or do you have a space problem with pulley also ?

[Val Popescu]

I don't know what is the problem I have! I'm helping a friend who bought a 4AG motor and was delivered with no alternator. I used to drive a DB4 followed by RT41 and both had alternators with large pulleys. Just don't remember the make/type.

Thanks,
Val

[Joules5]

What are you running electrically that demands an alternator? I run a 4AGE (carbs) in a 90 Reynard and no alternator (no data acquisition either), we just use a starter battery so as to not drain the on board.

If you do need an alternator then Jegs, Pegasus Auto Racing all sell mini denso style alternators.

Julian

[quartzracer]

Val, The alternator used is from a Kubota tractor. You can find them on Ebay they are small cad plated units. I can photo one that I have and send it to you. Not sure where to get the pulley though.

Eric

[Val Popescu]

Has EFI and data logger.
Yes a photo would be great so I can match it to what I find on eBay.
Thanks.

[quartzracer]

Here it is. Val I can loan you a complete unit with brackets and pulley if you want to copy it or possibly make a couple so we have a spare?

[DB4 Tim]

How large diameter and how much weight is there

[quartzracer]

Look closely, this is the same alternator from Hasselgren.

[john f]

Here it is. Val I can loan you a complete unit with brackets and pulley if you want to copy it or possibly make a couple so we have a spare?

What are you using for a voltage regulator with this unit? Thanks much.

john f

[Rick Iverson]

Look closely, this is the same alternator from Hasselgren.

Eric;

I caught a thread where Dave Weitzenhof installed one of these on his Zetec FC. He relayed there is considerable under-drive in the area of 65/35 to protect the alternator, as typified in your photo. Does Paul have kits available for FC Pintos, perhaps?

[Stan Clayton]

Val, my two 4AGE FA engines used the Denso alternator with an underdrive pulley. You can buy them all day on eBay for less than $100. They're a true self-exciting 1-wire alternator with internal regulator, and mine ran for 15 years without issue (they didn't fail, but were destroyed in the fire).

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313&_nkw= small+denso+alternator&_sacat=0

[Jerry Kehoe]

I have used the John Deere/Kubota unit for 20 plus years now, mine requires a separate solid state regulator to work. It's possible newer models have this built in, but not sure. It was used by lots of people on home built/light aircraft in years past and is a 20 amp unit but doesn't generate much until it is spinning at 1100 rpm itself and puts out 14.5 volts at 1500 rpm. Remember this is unit rpm not motor. When installed on a tractor it was overdriven quite a bit to achieve the 1500 rpm voltage. Stan's solution would be much cheaper from what I recall these cost when I bought it as you had to buy the regulator and alternator separately. Unfortunately I don't have the space for the Denso unit. I see now Amazon has them including the regulator for $99 and believe it or not Walmart shows them for $61. We machined the pulley shaft down, made a spud and installed a gilmore belt pulley, which you can get in a bunch of sizes.