pcard

I am having a debate about the correct pulleys to use in a 1970 SX with the Y72 option without AC. The photo attached shows page 93 of the asm manual section 6-1. It clearly indicates that the Y72 option uses three grooved pulleys on the crank and water pump, even if AC is not installed. In addition the parts manual lists the fan pulley for HD Cool (Y2) as part 399404 3 groove 6 1/8".

However, I am being told by reputable sources that this was not done, and that if there was not AC then two grooved pulleys were used. I agree that for a W30 machine this is the case, or VO1 or VO2 options. But I am not confinced about an SX with Y72.

Has anyone ever seen a regular F85 with Y72 with no AC showing a 3 groove pulley?

Thanks, Peter

pcard

Here is the photo of the asm manual page:

pcard

If someone has a buildsheet sitting aorund for a 70 Cutlass that had the Y72 option please give me a shout.
Thanks.

1969w3155

Copy of build sheet

pcard

Thanks so much!

Does anyone else have a 1970 buildsheet with Y72? ESPECIALLY one without AC?

rcorrigan5

My '68 442 has the Y72 option with the high amp alternator and no A/C. It came with the 3-groove pulleys on the water pump and crank, and the forward-most groove on both pulleys is not used. My car also has power steering with a two-groove pulley, of which the rear-most groove is not used.

The heavy duty option always got the high-amp alternator, even though the car didn't have A/C. The idea was that people who ordered HD cooling were probably going to put a trailer hitch on the car for towing and would need the extra amps for additional lights and so forth. If you have HD cooling but aren't going to do any "extracurricular" stuff with the car, the lower amp alternator would do just fine. But they didn't come that way originally.

I don't know if what applied in 1968 also applied for 1970, but if your car had the 3-groove pulleys on it when you bought it, plus the HD water pump (p/n 404847 or equivalent) and 4-core radiator, and the belts all lined up as described above, I'd say the odds are pretty good that it came from the factory that way.

Randy C.

pcard

Hey Randy - you wouldn't have the build sheet would you.

Even so you just won me lunch.

joesw31

The Y72 option used two groove pulleys and the parts books also state so for 1970. You do not need a build sheet to prove this.

pcard

A plethora of proof - the build sheet for me is the ultimate confirmation since at this time we can no longer be sure of anything that is presented as original.

rcorrigan5

All I have for my '68 is the window sticker - no build sheet. The assembly manual for '68 shows the Y72 option, though, with decent drawings of the three groove pulleys. The '69 assembly manual has even better pictures of the Y72 option set-up with the pulleys. I don't have a '70 assembly manual but I would think it would also have some nice drawings showing the pulley set-up for the Y72 option. I haven't looked as of yet but, if you don't already have an assembly manual for your '70, you might find one at www.wildaboutcars.com. If it's there, you can open it, go to the page you want to see, and print it (you can also print the entire manual if it's there).

Anyway, be sure to order the sandwich that has two patties!

Randy C.

pcard

Thanks Randy. I think your car is one that I accept as original!! I just wanted to go with shock and awe to win a bet I had with an old pro. As I said above, you have won me a free lunch. I will make sure to order a very nice bottle of wine.

rcorrigan5

I was going to add the pictures below but forgot in my last post. One is my window sticker which doesn't explain a whole lot except that my '68 doesn't have A/C and that it came with the Y72 option.

The second picture is out of the '69 assembly manual and shows the pulley set-up for heavy duty cooling with power steering. The picture for '68 is not as good or descriptive, in my opinion, but all the part numbers are exactly the same as this picture out of the '69 assembly manual. Hopefully, you will find the same (or similar) picture in the '70 assembly manual.

Randy C.

507OLDS

If it has AC,then it has 3-groove crank & water pump pulleys,and 2-groove power steering pulley.
If it is non-AC,then it has 2-groove crank & water pump pulleys pulleys,and a single groove power steering pulley.
The style of water pump will dictate the correct water pump pulley needed.The 847 X water pumps are the longer ones for 1970,and require a water pump pulley with a deep offset.The shorter water pumps have more of a flatter pulley.

pcard

Randy: the window sticker is great documentation, thanks. The picture I put at the top of the thread is the page from the 70 manual and it matches the 69 data. The fact that your car actually has the three groove pulleys is pretty convincing evidence when combined with the asm manuals.
Brian: your feeling is one that is shared with a few people, but I think that Randy's window sticker, and his actual setup makes a good case that in fact the Y72 option delivered with PS and without AC had the 3 groove crank and water pump pulleys, and the 2 groove PS pulley.

I am still in search of a build sheet showing Y72 with no AC (C60) to fully convince the skeptics. If anyone has one please let me know.

Thanks, Peter

MDchanic

Quick question that may shed some light:
Are the diameters of the 3-groove and the 2-groove water pump pulleys the same or different?
I don't have two sets to put side by side.

- Eric

507OLDS

The 3-groove pulleys are different diameters than the 2-groove pulleys.If,and I mean "IF" you had a 1970 Cutlass/442,with the HD cooling,no AC,and had the 3-groove water pumps & carnks pulleys,and the 2-groove power steering pulley,you would end up with empty grooves,meaning you would have a pair unused on the crank & water pump,and 1 groove unused on the power steering. Why? You would not have the AC compressor,which needs the 3rd groove.
If you have a non-AC car,with or without HD cooling,you have 2-groove crank & water pump pulleys,and a single-groove power steering pulley.You will have 1 belt that wraps around the crank,water pump,and alternator.The other belt wraps around the crank,water pump,and power steering.
If you have an AC car,you have the same belt assignment as the non-AC,plus you have the belt that wraps around the crank,water pump,and AC compressor.
AC gets 3-grooves.Non-AC gets 2. I have owned over 40 of these cars,and I have seen plenty that were unmolested originals.
The only cars that came with empty grooves,were the cars with manual steering.If you have a car with no-AC,and manual steering,you got a single-groove water pump pulley,but they still used the 2-groove crank pulley.They just didn't put any belt on it.You just had one belt on the entire engine,wrapping around the crank,water pump,and alternator.
If you had an AC car,with manual steering,which they did make,you had 2 belts on the engine,and the middle groove was empty.The manual steering engines still had the studs installed for the power steering pumps.Why?Because the engine was assembled before it had an exact car to go into,therefore they would not know if it had power steering or not.

pcard

From the Parts Catalog the following fan pulleys were available for 70 (NON Toronado):
405462 - 2 groove, 7 5/16 inch, F85 exc (AC, HDC, OAI)
405461 - 2 groove, ?? inch, 4200 HD Rad, or 4400 OAI exc AC
399404 - 3 groove, 6 1/8 inch, V8 with AC or HDC

Additionally:
taken from the Factory Installed Option section in the 442 Information Kit.

For reference the option codes
C60 = A/C,
Y72 = Heavy Duty Cooling and 55amp Decatron generator.

Factory Cooling Options:
Code VO1 was the Heavy Duty Radiator Code EC part number 3017107, 4 core – not available with the Y72 or C60 options, mandatory and available only with 3.91 axle, except it is mandatory with the 442 W30.

Code VO2 was the Heavy Duty Radiator Code FE part number 3014745, 3 core – not available with the Y72 or C60 options, mandatory and available only with 3.42 axle.

Code Y72 was the Heavy Duty Radiator Code ED part number 3017108, 4 core – not available with the VO1, VO2 options, not available with W30 or W31, not available with 3.91 or 3.42 axles. Mandatory with W33 (police use). Available with or without C60.


So if you wanted heavy duty cooling and you were not a 3.91, 3.42, or W30 you had to go with the Y72 option, which included a heavy duty radiator and heavy duty generator. It was available with or without C60 (AC).

So it is possible that some cars with the 4 core rad and no AC had the 2 groove pulleys, and some with HDC and no AC still had the 3 groove pulley.

Randy has indicated that this was the case in his car.

MDchanic

If the pulleys were different diameters, the 3-groove pulleys may have been used in some cases to spin the water pump faster, especially at idle in traffic.

Picture Mom, Dad, three kids and the dog with the Airstream hooked up in back, crawling along the NJ Turnpike with the A/C on on a 95° day.

- Eric

507OLDS

Randy's car is also a 69,isn't it?I know things were real similar between the 2 years,but still different,and they were still changing things for 1970.
I have only owned three 69 442's,so I don't have much to go on.However,all three of them had the HD-cooling.The Fremont-built car had AC,and the 3-groove pulleys.The Lansing-built car was non-AC,and had 2-groove pulleys,and this car also had every single original piece on it,even the plug wires,parked in 1976 and never driven again.The Canadian-built car was a 4-spd,no AC,with 3:73 rear,and it had the 2-groove pulleys as well.The Canadian-built cars came with 12-bolt Chevy rears,and therefore the 3:73 ratio was available.All of the other Cutlass/442's that I have owned,were/are 70-72,and I have not seen a 70 non-AC,with HD-cooling,and have 3-groove pulleys.They all had the 2-groove pulleys,or the single-groove with the manual steering.No,I have not owned all of them,but a fair share to see a common pattern.

joesw31

Brian, I am thinking the Y72 radiator had the two grove pulleys and the radiator was a three core tank on one end , and the filler tank was a 4 core tank. Again, only three cores.

Also, I went back to my parts book and found that Brian stands correct.

All cars without A/C got a two grove carank pulley P/N 405459.

All cars with H/D cooling no A/C got the two grove water pump pulley p/n 405461. That states: 3200, 3600, 4200, H.D. rad. this means F-85, Cutlass, Cutlass supreme.

Without H/D cooling and no A/C. The water pump pulley was P/N 391113.

And ALL H/D cooling used water pump P/N 230900, and that number changed to 231933.

joesw31

In this case there is no reason for a build sheet since the oldsmobile chasis and body parts catalog clearly states what part should be ordered.

507OLDS

I have one of those radiators that you are describing,with the wider tank on the fill side.Can't remember exactly what it came out of though.I know I had a few other like this in the past,that came out of Deltas or Toros,but not sure if I ever pulled one from an A-body.

pcard

Hey Brian: my experience with this does not even register when compared to yours, and errors have been made in parts lists and manuals before.

I just find it interesting that two years of asm manuals and both the 72 and 79 editions of the parts catalog would have the same, and supporting part references.
Also, the parts catalog explicitly differentiates between:

Pulley 404561 - 2 groove for:
- 4400 with OAI (consistent with W30 with manadatory VO1 heavy duty Radiator)
- 3200,3600, 4200 with heavy Duty Radiator (VO1 or VO2)

and
Pulley 399404 - 3 groove for:
- V8 with AC, HD Cool or Generator ( Y72)

I believe that the VO1 and VO2 options called for a 2 groove pulley while the Y72 option called for the 3 groove.
I imagine that the VO1 and VO2 options where much more common than the Y72 option without AC, and so these are the ones that have formed the collective opinion.
Eric has asked a good about fan pulley diameters: can anyone provide the diameter of a 2 groove pulley from a W30 or any VO1, VO2 optioned car.
The 3 groove is 6 1/8".
Since the PS belt length and PS Pulley for the 442 with AC is the same as the W30 (mandatory option VO1) (reference the WAC 442 Info Kit page 33 of the pdf) I would assume the 2 groove will be the same, 6 1/8".

joesw31

The VO1 option was a 4 core radiator with large tanks.

The VO2 option was a 3 core radiator with small tanks.

The Y72 cars that I toke apart: one from calaifornia, and the other was from Arizona. Again, both cars had no A/C. And had two grove pulleys.

I was mentioning the parts books because they are extremely accurate, and is not like the service repair manual.

Also, the W31 used the same cooling system as the W30.

I will measure the water pump pulley on my car.

MDchanic

Not necessarily.

IF the 3-groove crank pulley were bigger than the 2-groove, and
the 3-groove water pump pulley were smaller than a 2-groove, then
the fan belt length would be roughly the same, but the water pump would spin faster with regard to the crank.

- Eric

pcard

Eric - you are correct; I failed to refer to the parts catalog which indicates that the crank pulley for Y72 was the same as the crank pulley for AC: 399405. It does not give the diameter of this pulley.
This is consistent with the 1970 asm manual, section 6-1 page 92 and 93 which show the same pulley for AC or Y72 with no AC, 399405 code "KC", 3 groove.
The fact that this is a 3 groove pulley for either AC or Y72 gives me further cause to consider that the fan pulley was also 3 groove.

If this is being beaten to death I am sorry. I am installing a 4 core radiator into my SX with no AC and really want to be as faithfull as possible to what the factory would have done.

So far I have anecdotal evidence that this setup would call for a 2 groove fan pulley, 2 groove crank pulley and single groove PS pulley. And believe me, even outside of this post I am getting SERIOUS affirmation of this from very experienced people.

Countering that I find in the parts catalog and the asm manual clear documented evidence that indicated that Y72 without AC requires the 3 groove crank and fan pulleys, and 2 groove PS pulley. I also have one bit of anecdotal evidence supporting this.
In addition, there is a very plausible explanation why so many people have seen 4 core radiators, without AC, fitted with 2 groove pulleys, that is it could be that the car had the VO1 option.

I am leaning towards thinking Y72 had the 3 groove pulleys, and am looking for one of three things that would help conclude the debate one way or another:
- finding a page in the asm manual which talks to the VO1 option, or
- getting a buildsheet with the Y72 option and no AC, or
- getting documentation and photo evidence from an original car with Y72 and no AC

rcorrigan5

Just to clarify a couple of items:

1. My 4-4-2 convertible is a '68.

2. This 4-4-2 has been owned since new by my dad, then sister, then dad, and then me. It stayed in the family its entire life. None of the pulleys were ever changed out. It came new with the 4-core radiator.

3. My car was built at the Lansing plant in the first week of April 1968.

4. My car is built exactly the way the assembly manual says it is supposed to be - with 3-groove pulleys on the water pump and crank and the 2-groove pulley on the power steering pump. The '69 assembly manual shows the same thing. And, I see the '70 assembly manual is also consistent with the '68 and '69 manuals.

5. Here's another little experience (back in the mid-90s) that demonstrated to me the difference between regular cooling and heavy duty cooling. My brother has a '68 4-4-2 holiday coupe, also built in Lansing. He needed to replace his water pump and I had an extra hd water pump in my shop that I gave to him, thinking it would swap out with his perfectly. I was wrong. He installed his new water pump and put on his 2-groove pulleys and nothing lined up - as I recall, there was even a fit problem with the 2-groove pulley going on the water pump. There is a difference (as has been discussed in previous posts) between the regular water pump and the hd water pump. Upon further inspection, we discovered his car had the 3-core radiator and the regular 37 amp alternator (correct number and date consistent with the build date of the car). We did a little more digging and discovered how that difference works (with the two different water pumps and the pulleys involved with each) and that's how I learned about the Y72 option.

I don't know if anything changed between '68 and '70 (sometimes things did change and it took a little time for those changes to catch up in the assembly manuals) but I do know mine came from Lansing with the 3-groove pulleys on the waterpump and crank and the 2-groove pulley on the power steering pump, along with the 4-core radiator.

Randy C.

507OLDS

When comparing the diameters of the pulleys,fron the 2-groove to the 3-groove,the 2-groove water pump pulley is larger than the 3-groove,and the 2-groove crank pulley is smaller then the 3-groove crank pulley.
pcard,
When converting your car to the 4-row radiator,you will need to replace the perches on the core support,for the bottom on the radiator,and you will also need a 4-row top plate,but I'm sure you know that.
If I remember correctly,the HD-cool pump,for 1970,is 5 5/8" long,and the standard-cool pump is 5 1/8".This is where you need the correct water pump pulley,with the correct offset,so it lines up with all of the other pulleys on the engine.

joesw31

You will also need to find the correct fan clutch that was part of the Y72 option (heavey duty cooling/ towing package).

Look at page 6-1 -age 110 of your assembly manual. They list the fan clutches there.

joesw31

Brian, one of the nicest 4 core plates that I found off off a arizona Y72 car. It had the akward radiator insulators on one side.

MDchanic

So there is, in fact, a logical reason why 3-groove pulleys would be used in some cars with HD cooling options.

- Eric

joesw31

The three grove pulley is designed for cars with a/c as the a/c water pump spins faster at lower speeds / rpm. Further, the impeller on the a/c water pump is different, and the inlet size is also different. Therefore, HD cooling, and Y72 cars used a different lower radiator hose. The lower hose is coded as such.

pcard

Randy - could you measure the diameter of your fan clutch for me - it will be the OS clutch and I will need one.

thanks, Peter

pcard

Hey Joe - thanks for the comment on the fan clutch. I have a separate thread going about the clutches - check it out.

pcard

Hey Brian - thanks - that is the pump you sent me!

507OLDS

Hey,I didn't learn all of this overnight.Glad I could help.
Joe,I have seen those insulators.The channel that the radiator sits in,is not carved-out as long,but the overall length of the insulator is the same length,to fit the bigger perches,tabs.

shatrab

My "KA" waterpump pulley is a 2 groove pulley that measures 7.040 diameter. I recently learned that KA is for the W30. The engine side of the pulley is being used, while the front is not (I don't have power anything or ac). This is response to #23

507OLDS

Shatrab,
Does your car have manual steering?

shatrab

Yes.

507OLDS

Not sure what they made for 68,but this is how they did it for 1970.this is a manual-steering,non-AC,standard cooling.I have another 70 like this with HD-cooling,and also has a single-groove water pump pulley.My 71 W30 is manual steering,and has a single groove pulley as well.They all still came with the 2-groove crank pulley,which leaves one groove empty.
Burgundy70Cutlass008.jpg