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Fan Pulley

MoparThunder

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I have a 1968 Charger R/T with a 440. My power steering pump was leaking and a shop changed it out. After 2 were sent they said they finally received the correct one. Well I drove it home and found the belt is rubbing on the pulley now. What is the width of the correct pulley that is suppose to be on my car? Trying to figure out if the wrong pulley is on there or if they installed the wrong pump.
 
Could you just post a couple pics?
 
I have a 1968 Charger R/T with a 440. My power steering pump was leaking and a shop changed it out. After 2 were sent they said they finally received the correct one. Well I drove it home and found the belt is rubbing on the pulley now. What is the width of the correct pulley that is suppose to be on my car? Trying to figure out if the wrong pulley is on there or if they installed the wrong pump.

YES....pixs are great....but do you know what pump you have? SAGINAW or Federal or TRW (Thompson-Ramo-Wollridge). You want to know the sheave OD, Pitch Diameter, and belt width or ????
BOB RENTON
 
Just a WAG, but I'm thinking his belt is rubbing on the bottom of the water pump pulley.
To large of a pulley on the ps pump ?
To long of a belt ?
Like posted above , need pics.
 
Sorry it took so long to post a few pics. let me know if you think i need to show more. I can take a few pics of the old pump also. never had an issue until it was changed. I was told the pump that was on there or the pulley on the pump was for a Hemi car because the hole diameter was too large for the one ordered. So a different pulley was put on and now it rubs the fan pulley.

power steering pump.jpg power steering pump1.jpg
 
Sorry it took so long to post a few pics. let me know if you think i need to show more. I can take a few pics of the old pump also. never had an issue until it was changed. I was told the pump that was on there or the pulley on the pump was for a Hemi car because the hole diameter was too large for the one ordered. So a different pulley was put on and now it rubs the fan pulley.

View attachment 1229495 View attachment 1229496

IMO.....you have a Federal pump assemnly. Looking at the high pressure hose to the steering box, it a
APPEARS to be incorrectly routed, but it may just be positioned incorrectly. As far as the sheave's OD, do you recall what was size on the old pump? The diameter of the sheave will determine the pump's volume capabilities. Perhaps the steering assist volumes are vehicle model/engine specific to allow for different vehicle weights? I do not have my parts lists handy to verify ..... pethaps someone can check. I've seen on other installations, a light "footprint" of the PS pump's belt interference on the OD of the water pump's sheave OD, similarly to what you are experiencing, without any problems.....
BOB RENTON
 
IMO.....you have a Federal pump assemnly. Looking at the high pressure hose to the steering box, it a
APPEARS to be incorrectly routed, but it may just be positioned incorrectly. As far as the sheave's OD, do you recall what was size on the old pump? The diameter of the sheave will determine the pump's volume capabilities. Perhaps the steering assist volumes are vehicle model/engine specific to allow for different vehicle weights? I do not have my parts lists handy to verify ..... pethaps someone can check. I've seen on other installations, a light "footprint" of the PS pump's belt interference on the OD of the water pump's sheave OD, similarly to what you are experiencing, without any problems.....
BOB RENTON
Thanks for your response. I believe you are correct. I want to make sure I know what you mean, the sheave's OD you mean the pump pulley? I think the old pump was a Saginaw. The old pulley was 4.75" dia and the new one is much larger at around 7". Here are a few pics on it. I still have it.

IMG_1468.jpg IMG_1469.jpg
 
Thanks for your response. I believe you are correct. I want to make sure I know what you mean, the sheave's OD you mean the pump pulley? I think the old pump was a Saginaw. The old pulley was 4.75" dia and the new one is much larger at around 7". Here are a few pics on it. I still have it.

View attachment 1229564 View attachment 1229565
I think it may be a matter of nomenclature.....in industry, belt drives systems on gear boxes, pumps etc, call the power transmission equipment sheaves. Conveyor belts use pulleys to drive the belt..... any way, If the old pump was a Saginaw pump, it had an OVAL filler neck and the pressure supply and return ports were on the REAR of the pump's housing. FEDERAL pumps use a round filler neck and the high pressure connection is on the front face at about the 2 o'clock position. And the sheave attachment is different and the Saginaw pump drive sheave is USUALLY a larger OD with 3 spokes. If you still have the origional pump, they are rebuild-able.....shaft seal, O-rings, etc. from NAPA, Rock auto, and one of the forum suppliers. The FSM goes into detail about the pump assemblies, both types, how to rebuild it, etc.
BOB RENTON
 
Can you put pulley from old pump to new one? The diameter of pulley is most if not all of your problem. Is the belt hitting the front edge of pulley grove or just the nose?
 
Can you put pulley from old pump to new one? The diameter of pulley is most if not all of your problem. Is the belt hitting the front edge of pulley grove or just the nose?
I was told that the old pulley did not fit the new pump so they ordered a new one and installed it on the new pump. Something about it fitting a hemi car which I am not sure of. I think that was just the parts guy guessing. I agree, there is a big difference in diameter between the 2 pulleys and should be the problem. Back years I had a cooling problem and the mopar guy I used decided that the issue was partly the clutch fan so he took it off and put on this fixed one. Yes, i have never had an issue since then and it drives very cool most of the time. but I'm wondering if he changed the fan pulley.
 
Fan pulley looks correct.
If the new ps pulley is that large.. of course it's going to decrease clearance. Even with the stock pulley they were close enough to touch. Plus you're under driving your ps now. (Maybe not such a bad thing lol)
 
I was told that the old pulley did not fit the new pump so they ordered a new one and installed it on the new pump. Something about it fitting a hemi car which I am not sure of. I think that was just the parts guy guessing. I agree, there is a big difference in diameter between the 2 pulleys and should be the problem. Back years I had a cooling problem and the mopar guy I used decided that the issue was partly the clutch fan so he took it off and put on this fixed one. Yes, i have never had an issue since then and it drives very cool most of the time. but I'm wondering if he changed the fan pulley.

Yes....it's possible but the clutch fan mounts to the water pump shaft and sheave the same way but a solid drive fan uses a spacer and different bolts. It's unlikely that the water pump sheave was changed, but possible. Actually, the clutch drive fan uses less HP at high RPM, but the water pump is still turning the same RPM, for cooling purposes. IMO....it's unfortunate that the first person just didn't replace the detective fan clutch....aftermarket units are not expensive and perform well. The origional system used a seven (7) blade fan and the clutch limited the fan's RPM, but not the water pump speed to use LESS power at interstate speeds. Now, with a solid drive fan arrangement, it's moving more air than needed st highway speeds. Personally, I would have just rebuilt the leaking PS pump.....but since you still have it, its not too late to do so, re-install the origional drive sheave and retain the existing solid drive fan.....
BOB RENTON
 
Fan pulley looks correct.
If the new ps pulley is that large.. of course it's going to decrease clearance. Even with the stock pulley they were close enough to touch. Plus you're under driving your ps now. (Maybe not such a bad thing lol)
I'm more worried that the belt will eventually wear enough on the fan pulley to break while I am driving. If I could get 1/4 inch i would be happier.
 
Yes....it's possible but the clutch fan mounts to the water pump shaft and sheave the same way but a solid drive fan uses a spacer and different bolts. It's unlikely that the water pump sheave was changed, but possible. Actually, the clutch drive fan uses less HP at high RPM, but the water pump is still turning the same RPM, for cooling purposes. IMO....it's unfortunate that the first person just didn't replace the detective fan clutch....aftermarket units are not expensive and perform well. The origional system used a seven (7) blade fan and the clutch limited the fan's RPM, but not the water pump speed to use LESS power at interstate speeds. Now, with a solid drive fan arrangement, it's moving more air than needed st highway speeds. Personally, I would have just rebuilt the leaking PS pump.....but since you still have it, its not too late to do so, re-install the origional drive sheave and retain the existing solid drive fan.....
BOB RENTON
I was told by the shop that was what they were going to at first. Not sure why they changed their mind but before I could say anything they ordered and received one but the pulley didn't fit so they cal;le dback the parts guy adn ordered one that would fit. I talked to them about the difference with Federal. TRW, and Saginaw and they understood that so I had some confidence going in.

I'm just trying to figure if I can drive the car like it is or what I need to do to fix it. Waiting to hear back from the shop.
 
If you know the diameter of the shaft on new PS pump Put a want ad. Say what shaft diameter and OD of pulley you want.
 
I was told by the shop that was what they were going to at first. Not sure why they changed their mind but before I could say anything they ordered and received one but the pulley didn't fit so they cal;le dback the parts guy adn ordered one that would fit. I talked to them about the difference with Federal. TRW, and Saginaw and they understood that so I had some confidence going in.

I'm just trying to figure if I can drive the car like it is or what I need to do to fix it. Waiting to hear back from
Not sure why the shop could not get a saginaw pump and just install it and your pulley ?
Well were your at now is getting a smaller pulley for your now installed pump like was suggested or take a look at the adjustment slot for tightening the ps belt.
If you have some adjustment room left a slightly longer belt may get you some clearance.
That belt should drop lower from the water pump pulley as it is lengthened.
Not sure if that will get you enough room but worth a look.
 
That is not a Federal pump. Federal pump does not use that bracket and has a 3/8" dia thread hole in shaft. That is the Small TRW pump most likely. THat pump would have been correct for a 68, but I guess it depends if your pulley and all are correct. Do you have a picture of the pump that was originally installed?

If they went TRW to TRW the pulley should have fit (transfered) so I don't understand why it did not. Pulley off set matters and small block/big block pulleys have different offsets. Does the belt align properly to the bottom pulley or is it at an angle?

TRW used a 1/2" belt like hemi. The later saginaw belt went to 3/8".

By the way, your water pump pulley looks correct for the 68 big block. They added a spacer to the fixed fan, so the conversion of your fan drive is not the issue here. Looks to me like your PS pulley needs to move forward towards radiator some to have belt clearance on WP pulley.
 
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Ok, this is a follow up on this issue. It has been established the old power steering pump was a TRW. The new one that was installed is a Federal. Which is the correct one for a 1968 Charger R/T 440 HP? The sheave on the new one is 0.624 and the pulley itself appears to be almost 7 inches. Can I get a 6 inch pulley with that sheave dimension for a Federal?
 
The BB is 7", others will have a different offset. The Hemi is 61/4" but again different offset and pretty expensive as a repop. For 68 TRW is correct pump not Federal, even the hemi was TRW until late 68.
 
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