I have a 427/390 (L36) engine, power steering, no air conditioning.

How many belts am I supposed to have with this configuration and how should they be routed?

Currently, I have two belts:

#1 belt goes around the water pump, crank pulley, and power steering pump.

#2 belt goes around the power steering pump and alternator.

Is this right? Or did Bubba screw this up years ago?

 

Sounds right....have alook at the picture on this page...

http://www.parts123.com/parts123/yb....~Z5Z5Z5~Z5Z5Z5

Good Luck,
Joe

You'll see there is a third belt around the crank and water pump only

 

Hmmm....

Is there a reason for the third belt between the crank and water pump? Isn't this just another drag on the horse power (and another potential source for squeaks)?

 

There are probably two reasons. One, it provides a degree of redundancy if you break the p/s belt...you can keep driving because the water pump is still driven. Second, it might help ensure the water pump is driven more securely as the power steer belt only does a quarter turn around the crank pulley...less chance of slippage.

That said, this little belt is a bear to get on as there is no adjustment. Having got the correct belt, you need to remove the fan and water pump pulley, slip the belt around the crank and water pump pulley and then fit the water pump pulley back on with the belt already on.

Cheers
Joe

 

Got it. That makes sense.

Well, given that I'm about to replace the radiator and water pump, this might be a good time to reinstall this little belt. I like having the redundancy.

 

I have the same car and engine. AC has been deleted. I thought the same as you, but, after continued problems with high water temp. and belt squeel, I installed the little belt--yes the above info is correct, you have to take the pulley off inorder to install the belt-- and the water temp dropped about 15 degrees and the squeeling stopped. I think the water pump belt was slipping.

 

I have the same L36 setup on a 67 with power steering only and it is stock with the correct pulleys.

There are three belts:

Belt No. 1 is from the crank pulley to the water pump (inner groove on both pulleys). This belt is GM Part #3433722, FC#440x330, or Dayco #0793:11. You have to take the water pump pulley off to get this belt on and you have to put this belt on first.

Belt No. 2 is from the crank pulley, to the water pump, to the power steering pump (outer groove on the crank pulley, outer groove on the water pump, and the inner groove on the power steering pump). This belt is a 15-456Y and this belt goes on second.

Belt No. 3 is from the outer groove of the power steering pump to the alternator. This belt is a 15-332Y and it goes on third.

Put all three belts on but leave the alternator belt loose. Adjust the tension on belt No. 2 by adjusting the power steering pump. After belt No. 2 is adjusted, adjust the tension on belt No. 3 with the alternator.

This set up works for BB cars with power steering. If the car has AC or AIR the water pump pulley will have three grooves. Otherwise it will have only 2. If the car has AC or AIR, the belt in the outer groove of the water pump pulley runs those items.

I had a lot of trouble with this when I set mine up so I know what you are going through.

 

I asked the same question!! ... about 4 years ago!

http://forums.corvetteforum.com/show...ighlight=belts


In 1968 all cars had the AIR pump, so the stock L-36 with power steering and no A/C had 4 belts! I also have only the same 2 belts that you have. I am currently having a heck of a time lining up my p/s pump while tightening that long belt. Will try something different tomorrow.

Apparently the high revving engines (this would NOT include the L-36 ) had a tendency to throw the p/s belt, while the tighter fitting waterpump belt would stay on. It's supposed to be a real biotch to put on.

 

Thanks, everybody - this information has been very helpful!

 

If you have the Assembly Instruction Manual, AIM, for your car, there will be a page that shows exactly what belts and where, go on your car. They have a diagram for each of the various combinations of accessories and pulleys.

Gary

 

Tele_Man, I just noticed your other post about high rpm squeal. My car does that too! I could live with that, but the noise got a lot worse the other day prompting me to change belts.


I could post the belt diagram from the AIM, but 67-73-76 provided a detailed description already (as they say, 1000 words is worth a picture!) and it's pretty clear that you (and I) have 2 of the 4 factory equipped belts.

 

PRNDL,

I agree. Looks like we're missing belts. I want to get my hands on one of those AIM's. I'm sure this assembly manual will be a valuable reference tool.

Does your water pump pulley have three grooves?

I'm assuming that the third groove goes to the A/C unit. RIght?

Did all 68/69 Vettes have a three-groove water pump pulley, of did my car originally come with air conditioning?

 

Not air conditioning, but Air Injection Reactor (A.I.R) also known as the smog pump. All 68s, and I think all 69s came with A.I.R. I only have a 2 groove pulley for the waterpump, but it should certainly be a 3 groove for the 3 belts: 1 going up to the AIR pump, 1 going down to the crank (that's the waterpump belt we dont have) and 1 going down to the crank and around to the p/s pump. The 68 AIM has 2 full pages with nine different belt configurations depending on engine and options!! I will scan it just for fun. The bigblocks with A/C just ran a longer belt around the AIR pump that also powered the A/C compressor.

 

smallblock belt configurations:


bigblock belt configurations:

 

Holy Toledo!

This information is WAY cool! Thanks, PRNDL!

I also ordered an AIM for my car.

I can see now why my belts are squealing and I need to get things back into the proper configuration.