Topic: 69 Dearborn 390 Engine Pulley

[G Wood]

I am assembling the front of the engine and want to ensure I have the correct pulleys. The car does not have AC and does not have smog. It does have PS.

Using the Osborn manual as a reference, I have a single alternator pulley, two groove crank pulley, and would need a single groove for the water pump. I currently have a 2 groove for the water pump but I am unsure if this was original to the car or not.

[Bob Gaines]

I am assembling the front of the engine and want to ensure I have the correct pulleys. The car does not have AC and does not have smog. It does have PS.

Using the Osborn manual as a reference, I have a single alternator pulley, two groove crank pulley, and would need a single groove for the water pump. I currently have a 2 groove for the water pump but I am unsure if this was original to the car or not.

One groove of the WP pulley is for the alt and the other groove is for the PS. PS pulley is C6AE-A .

[G Wood]

That was my original thought but posts I have read elsewhere and the manual indicate the PS belt only goes to the crank and not to the water pump. Do you know which belt I would need for the PS as the one I have purchased will not work?

[Bob Gaines]

That was my original thought but posts I have read elsewhere and the manual indicate the PS belt only goes to the crank and not to the water pump. Do you know which belt I would need for the PS as the one I have purchased will not work?

that is the way I have always seen them and pg 81 of the assembly manual reprint seems to support my observation.  The belts and their lengths are listed there too. Probably best for you to revisit that page so you can confirm my post vs. the other anonymous posts you have read . FYI a air car would have a additional crank pulley groove but the A/C or non A/C  390 application uses the same WP pulley because the belt doesn't run off the WP pulley.

[G Wood]

Bob, thanks for your assistance, I'll take a look once again to confirm.

[Bob Gaines]

Make sure you have the correct P/S pulley too. That will effect belt length and alignment also  .  A air pulley and a non air pulley have a different offset besides any diameter difference.

[G Wood]

Bob:

I was using page 54 as a reference for a non-AC car. The application chart on that page is not very clear but I thought it said for 390GT application. Page 81 indicates it is for a AC application but I can see that the belt configuration includes the water pump. I don't have any references cars to look at in my area so I'll go with your advice, just wanted to ensure you were referencing a non-AC car. Thanks again for you help.

[Bob Gaines]

Bob:

I was using page 54 as a reference for a non-AC car. The application chart on that page is not very clear but I thought it said for 390GT application. Page 81 indicates it is for a AC application but I can see that the belt configuration includes the water pump. I don't have any references cars to look at in my area so I'll go with your advice, just wanted to ensure you were referencing a non-AC car. Thanks again for you help.

After looking at pg 54 I can understand the confusion. The illustration is for a Mercury Meteor with the pump mounted way up high instead of low like on a Mustang. I saw that and went right past it. I have always seen the 2 sheave pulley arangement on the water pump but I will admit that I don't work with a lot of 390 69's. The arrangement on pg 81 is what I am used to seeing (minus the A/C) on  67 ,68 390 and 428's heavy duty applications but now that I think about it those are all for double alt pulley except when used with A/C which is a single as in the illustration on pg81. The arrangement will work I discribed will work but in your 69 application doesn't appear to be assemblyline correct. It appears that if you want a assemblyline correct pulley set up you will have to go with the C8AE-C crankshaft pulley ,a 6 inch and not a 7 inch single  sheeve waterpump pulley and a 5.35 inch powerstering pulley with the correct forward offset.This is the info given on page 54.  With those correct pulleys the corresponding factory belt is 44 inch and should work. If you use the duel waterpump pulley you already have we could figure out what belt you need if we know what other pulleys (crank,p/s pulley) are involved.   Just decide which way you want to go and i stand ready to do what it takes step by step to help get you going.

[G Wood]

I agree it is a little confusing. for now I may just go with the double water pump pulley and track down a new belt while I look for a single pulley that I could change at a later time.  I'll look to see what belt will work and go that route.

thanks again

[Bob Gaines]

I agree it is a little confusing. for now I may just go with the double water pump pulley and track down a new belt while I look for a single pulley that I could change at a later time.  I'll look to see what belt will work and go that route.

thanks again

If you are going that route i would go with the belt over the waterpump pulley then the P/S pulley like on page 81 . That way you don't have a unused pulley sheeve that will look out of place. Just my opinion. FYI the nominal length belt for a given application will have the adjustment bolt typically midway in the adjustment slot.

[G Wood]

Bob:

I have seen a few photos of 428 engines on the web (one from an engine display at the Mid-America Shelby meet) that show the PS pump pulley going only to the crank. I did not want to post the pictures here as they are not mine but this would seem to support page 54 of the Ford Assy manual that I would need a single pulley on the water pump on the 390. The belts I bought from Marti (C6AE-8620) seems to fit crank/PS only. Thoughts?

[Bob Gaines]

Bob:

 I have seen a few photos of 428 engines on the web (one from an engine display at the Mid-America Shelby meet) that show the PS pump pulley going only to the crank. I did not want to post the pictures here as they are not mine but this would seem to support page 54 of the Ford Assy manual that I would need a single pulley on the water pump on the 390. The belts I bought from Marti (C6AE-8620) seems to fit crank/PS only. Thoughts?

At this point I don't think there is a dispute whether pg 54 in the manual is accurate in regards to 390'sand they seem to be different then 428's in that regard. Not to say you couldn't mix and match and make ether set up work on a 390 engine or not just that one is assemblyline and one is not. In your case as we reviewed in the previous post appears to be the single groove waterpump pulley. You just have to decide which way to go . Last post you mentioned that you may want to use the double pulley that you already had rather then source and use a single groove pulley. I have been very involved with the mid America Show and some of the engines on display in the past have been mine including a couple 428's . I am trying to think of what you my have saw and can only remember some of the 427's and not 428 that had a single groove water pump pulley that were displayed in the lobby . With few exceptions the 427's didn't typically come equipped with P/S. Typically the 428 would have the double pulley on the W/P.