Delco alternator mounting pattern?

[BioHazard]

I know with some of the older Delco alternators such as the 10SI and 12SI they mount in the same holes and brackets, even so with larger frame alternators like a CS144. I'm hoping to mount a 22SI alternator in my '73 chevy truck to power a 3kw inverter. Does anyone know if this has the same mounting pattern as the 10SI that I currently have? It looks really close when I hold it up but it's hard to tell for sure without removing the alternator....

Also, can anyone tell me how many amps I can produce with an alt being driven by a single V belt before it starts to slip?

[artificer]

According to this document from Delco Remy, the mounting style is different.  The 10SI has a small threaded mounting hole at the top, and a single wider hole at the bottom.  The 22SI has a split bracket on the bottom.  The hole spacing is also different.  6.6" vs 7.8" on the 10SI vs 22SI.

Since both alternators use a swinging top bracket, I don't think the difference in hole spacing will be a problem, as long as the 22SI fits in the space.  The bottom bracket needs to be different, however.

Michael

[TimSR2]

Anything over 75 amp will probably give you trouble with a single sheave. Get the largest diameter alternator pulley you can; this will give a bit more surface area "grip" .

You are going to need 2 grooves, or even a serpentine conversion.  The crank and water pump pulleys you need for double vee belts are pretty hard to find now, but if you have a wrecker in your area  that has that cars that old, look in the  P-vans, motorhomes, 1 tons, ambulances and police cars.  Also Mercury marine and Volvo chevy blocks have them. I'm looking for a set myself!

[SteveU.]

Hi BioH
Trade your 22SI for a 17SI.
These were available up to ~116-130 amps. Ups the case diameter by ~1". Splool foot hole to Upper adjustment ear hole wider by ~ 1.5".
TimSR@ is absolutely correct. You will max out at ~75amps/12.5 volts with a single "A" belt drive.
If this '73 is AC equipped it will be dual belt driven. Ditch it. And "sweat in" your 22SI in it's place being duel belt driven. Give you system redundency with two alternators on board.

Regards
Steve Unruh

[BioHazard]

You are going to need 2 grooves, or even a serpentine conversion.  The crank and water pump pulleys you need for double vee belts are pretty hard to find now

I've got an empty pulley on the water pump now, I think I can use that to double up. I'm considering a mini-serpentine conversion, soon my alternator and power steering will be the only thing belt driven. I'm replacing the fan and water pump with electric.

Hi BioH
Trade your 22SI for a 17SI.
These were available up to ~116-130 amps. Ups the case diameter by ~1". Splool foot hole to Upper adjustment ear hole wider by ~ 1.5".

I think I'm just going to go with a juiced up CS144 alternator, it should bolt right in. Not as big as the 22SI monster but it will probably do. I could make the 22si fit but I'm worried it's too long and would hit my valve cover...

[TimSR2]

Are your water pump sheaves the same diameter?  And you have  a spare on the crank too? Then it's just a matter of fabbing the brackets and running the wiring.  At least it's in a C-K chassis, where you have room to work.  

Don't get me going on G-Vans!  I love them but they are impossible to work on.....  They are the PT cruiser of the 70's/80's ....  way too tight in the engine bay!

[BioHazard]

At least it's in a C-K chassis, where you have room to work.  

Lol, yeah, ultimately I'd like to have four deep cycle batteries plus a starting battery and I'm pretty sure I can fit them all under the hood. 

[artificer]

Just came across this document from Balmar, about their alternators.  Not sure if this helps, but its one more data point.

Michael




The paragraph in question is:

*************************************************************************
Pulleys
Most small case alternators rated at 110 amps or less come standard with a single
groove deep vee pulley. The deep vee pulley is designed to provide optimal
power transfer for belts measuring 3/8" (10mm) to 1/2" (13mm), as measured
across the back of the belt. Keep in mind, 3/8" and 7/16" belts may sit low in
the pulley sheave. This will not adversely affect the belt's performance. Higher
output alternators (120+ amps) in small, large and extra-large case series
are equipped standard with 1/2" dual groove pulleys. Some models, including
622-Series alternators may be equipped with multi-groove serpentine
type pulleys. Should your application require a different pulley than that provided
as standard, Balmar may carry an optional pulley more suited to your
needs. For a list of optional pulleys, visit http://www.balmar.net/pulleymatrix.htm,
or call Balmar Customer Service at 360-435-6100.

************************************

[BioHazard]

Thanks for the extra info. I just realized the bottom of my alternator is mounted to the water pump, and I'm getting rid of that and going to electric. I'll have to fab up some kind of brackets anyway so I might as well try and shove that 22SI in there....

[vdubnut62]

Some of the "Greenie Weenies" would ask "Why don't you electrically drive the alternator too?"
I know people like that...........
Ron.