For a 1970 Cutlass, w/o AC:
can anyone tell me why the HD cooling option (Y72) calls for a different generator. I am referring to the assembly manual section 6-1 pages 92 and 93.
I can understand why a different size generator pulley may be required since the crankshaft pulley is a larger radius.

I am going to install a 4 core radiator and would like to get all the Y72 components right, but would like to understand their function.

Thanks, Peter

 

Hi Pete,

Good question! part#1100777 rated 60 amp, 1100890 rated 63 amp source for amps was Wilson aftermarket supplier for starters and alternators.
part #1100879/1100880 both are 42 amp.

Oldsmobile thinks that your going to tow trailers, more lights requirer more amp draw!

 

Can you tell me what was the output of the generators:
1100879 (or 1100880 for 442): w/o AC, regular cooling
and
5910729: with AC, regular cooling?

Did these generators all have the same radius pulley?

Are the crankcase pulleys 405459 (KJ)(w/o AC) and the 399405 (KJ)(with AC or Y72) the same radius?


Again: referrences are from the 1970 assmebly manual section 6-1 pages 92 and 93.

Also, note that on page 86 there is a note that to convert my engine (TQ) to Y72 all that is needed is to change the water pump (404655 to 404846) with no mention of any of the pulleys or the generator.

Thanks, Peter

 

Peter, I'll give you something to study here.
http://wildaboutcarsonline.com/cgi-b...aldisplayed=26
Start in section 2.274 of the '72 edition of the Chassis Parts Catalog. You'll see pulley and alternator (delcotron) listings.
I quickly noted that the part numbers in the assembly manuals have already been superseded by this '72 date. But you can still get some application info there. I was going to check some earlier catalogs at home later, but thought I'd give you a head start on what is in the '72 edition.

 

Thanks mate - love lots of info.
Seems that for 1970 the gen pulleys for HD Cool/AC and non AC were the same (part number 1949355 in the '72 edition).
While the alternator section leaves me a bit confused, the 442 site has a great section on alternators (http://www.442.com/tech/tech.html) , which confuses me even more since some information is not consistent between the two, and even with the assmbly manual: for axample, 442.com indicates that the standard generator for a 455 (non 442) was the 1100878 (42 amp), while the asm manual calls for a 1100879 (37 amp).

I will have to study these some more to find the rhyme and reason.

 

Just to clarify to those who may not know, the 442 alternator is different only in that it has an internal regulator. Olds started internal regulators in 1969 and like in '70, they were only available on the 442. Why? My guess is that because it was new technology and still not across the board, they decided to put it into their performance model to prove out.

 

Or, less weight = better E.T.'s!

 

General Motors has a habit of consolidating part numbers as the years go by from the original date of manufacture. This is for 2 reasons, one being that they might have run out of one part number inventory, and don't want to do a second run of the part, knowing that the substitute will work just as well. And 2, many times, the part is the same and has 2 different numbers because one will be a higher priced part for the higher priced automobile that it was originally installed on. Unless you have the two parts in your hands to compare the physical differences, it is hard to tell what, if any difference there actually is. I used to have a parts interchange book, that gave the part number for each division for the identical part. Many times, pulleys fit many different engines and accessories, and each division (Chevrolet, Buick, Pontiac, Oldsmobile, Cadillac, & GMC) each had their own part number and price. This book was a cross reference to each brand, and was set up in 6 sections with the first column being for a particular brand vehicle. I made the mistake of loaning to to a friend that never returned it. I guess that he felt that the book was more valuable than the friendship. He has since passed on, and I have no idea what happened to the book after he died.

 

Check this page out guys...
http://www.oldsmobility.com/mpc/grou...cotron_idx.htm