Saginaw for a serpentine IDI: brainstorming

[Gary Lewis]

Gary, since I am using the C2 bracket, and my goal is to keep the pulley in its current position relative to the bracket, my plan is to carefully measure the space between the bracket face and the back of the pulley and try to replicate that with spacers and how far I press the pulley on. The reason I asked about the distance between the block/head surface and the surface where the pump sits is just to anticipate whether a lot of spacing may be needed. Remember my original article where the guy had to space the pump aft about 5/8"? I'm just wondering why the difference... totally different bracket than either of ours, I know... but same plan of putting a Saginaw in a C2 bracket. I don't need an exact measurement, I just want to have some clue what I'm building so I can design it right.

Maybe I'm making this too simple, but in my mind the pulley's location has to be fixed. Has to, otherwise the belt will come off. And you are going to use the same bracket with either pump. So the distance between the back of the pulley and the bracket must not change. So, what we need to know is how much to move the Saginaw aft to put its pulley in the same spot as a C2's.

Assuming that your C2 pump and Saginaw pump are/will be the same as those I have, we can ascertain that distance in two ways:

1: Use a factory C2 and a factory Saginaw bracket and see how far aft the Sag's mounting point is from the C2's. That seemed easiest to me, so that's the approach I've been taking.

2: Assemble the two pulley/pump combo's and measure from the back of the pulley to the front of the mounting spot. The difference should be the amount of aft-set. I can do that to confirm the above approach.

I say all that to make sure we are all on the same page. Does that make sense?

[85lebaront2]

Maybe I'm making this too simple, but in my mind the pulley's location has to be fixed. Has to, otherwise the belt will come off. And you are going to use the same bracket with either pump. So the distance between the back of the pulley and the bracket must not change. So, what we need to know is how much to move the Saginaw aft to put its pulley in the same spot as a C2's.

Assuming that your C2 pump and Saginaw pump are/will be the same as those I have, we can ascertain that distance in two ways:

1: Use a factory C2 and a factory Saginaw bracket and see how far aft the Sag's mounting point is from the C2's. That seemed easiest to me, so that's the approach I've been taking.

2: Assemble the two pulley/pump combo's and measure from the back of the pulley to the front of the mounting spot. The difference should be the amount of aft-set. I can do that to confirm the above approach.

I say all that to make sure we are all on the same page. Does that make sense?

Here is another thought, the 1989 G30 van I repaired has a PS pump (Saginaw of course) with a remote reservoir, it is connected to the pump with a fairly large hose, fluid return is still on the back of the "can" as a normal setup would be. Here is the best picture I could find.

[Ford F834]

Maybe I'm making this too simple, but in my mind the pulley's location has to be fixed. Has to, otherwise the belt will come off. And you are going to use the same bracket with either pump. So the distance between the back of the pulley and the bracket must not change. So, what we need to know is how much to move the Saginaw aft to put its pulley in the same spot as a C2's.

Assuming that your C2 pump and Saginaw pump are/will be the same as those I have, we can ascertain that distance in two ways:

1: Use a factory C2 and a factory Saginaw bracket and see how far aft the Sag's mounting point is from the C2's. That seemed easiest to me, so that's the approach I've been taking.

2: Assemble the two pulley/pump combo's and measure from the back of the pulley to the front of the mounting spot. The difference should be the amount of aft-set. I can do that to confirm the above approach.

I say all that to make sure we are all on the same page. Does that make sense?

Gary I think we are on the same page. Your method 1 is basically what I have been saying we need to be able to anticipate the pump spacing and devise a good way to mount it in that position. I don't think method 2 is necessary. For me it will be, just to check the final result and verify that the transplanted pump/pulley matches the original. As you said, the location of the pulley grooves is all that matters. Everything else is irrelevant as long as that's correct. Well, the axis of the pump shaft matters some, but the movement of the tensioner buys a little flexibility as long as its close.

My only real design concern is forward spacing. Everything we have talked about is moving the pump aft compared to the C2. This is relatively easy with spacers and longer bolts. The adapter also moves it aft. But if it turns out to need forward spacing with the adapter in place that would be much harder. That is what the guy with the explorer conversion ran into. He solved it with not putting the pulley all the way on the shaft, but you can only fudge so much and that is less than ideal. As I mentioned earlier, if your method 1 shows zero difference between the brackets, then I anticipate.222" aft required. Which should be close to the adapter thickness.

[Ford F834]

Here is another thought, the 1989 G30 van I repaired has a PS pump (Saginaw of course) with a remote reservoir, it is connected to the pump with a fairly large hose, fluid return is still on the back of the "can" as a normal setup would be. Here is the best picture I could find.

Thanks! I may have to check some C30 vans to see if it might save me from butchering my bracket. I think would feel okay about transplanting a whole remote reservoir system, I'm just not keen on cobbling one together. I imagine the size of the lines between the reservoir and the pump are pretty important for proper function.

[Gary Lewis]

Thanks! I may have to check some C30 vans to see if it might save me from butchering my bracket. I think would feel okay about transplanting a whole remote reservoir system, I'm just not keen on cobbling one together. I imagine the size of the lines between the reservoir and the pump are pretty important for proper function.

Might the remote reservoir might solve both the interference with the bracket as well as the return issue?

[85lebaront2]

Might the remote reservoir might solve both the interference with the bracket as well as the return issue?

On that van the inner/upper of the two visible lines is the reservoir hose, it is approximately 1" ID from what I remember. Return is fairly normal GM style. Here is a picture of the engine brackets that shows the pump and lines.

[Ford F834]

FWIW, item 9 in the picture was missing and caused it to break two of the big "horseshoe" stampings.

Interesting. Neither of the V belt units that I pulled for my F150 had any kind of brace on the back side, but the brackets are steel. The 460 unit that I pulled for Gary did have a steel brace on the back. I wonder if I need to provide rear support?

 

[Gary Lewis]

On that van the inner/upper of the two visible lines is the reservoir hose, it is approximately 1" ID from what I remember. Return is fairly normal GM style. Here is a picture of the engine brackets that shows the pump and lines.

FWIW, item 9 in the picture was missing and caused it to break two of the big "horseshoe" stampings.

Bill - That looks promising.

As for measuring, I didn't want to get things dirty so spent most of the day cleaning the brackets. I think they came out rather well, but what do you think?

There are a couple of pics below that show the measuring setup with the brackets bolted to the mill table to ensure nothing can move. You can see the inside mic that I used for one set of measurements. And then I used the dial calipers and measured through the hole to the table and subtracted the thickness of the casting at the hole. The two methods gave really close results, like within .006", but I'm showing the caliper #'s as I have more confidence in them.

All measurements from the head mounts to the power steering pump mounts:

• Saginaw:

1:00 Position: 5.593"

3:00 Position: 5.595"

6:00 Position: 5.233"

• C2:

Top Outside: 5.675:

Top Inside: 5.670"

Bottom: 5.668"

If we say that the C2 mounts at 5.670" and the two Saginaw mounts are 5.594", then that says that the Saginaw should mount .076" aft of the C2. Not nearly as much as I expected, so am I thinking incorrectly? However, the difference between the Saginaw mounts are .361".

Here are the pics:

[85lebaront2]

FWIW, item 9 in the picture was missing and caused it to break two of the big "horseshoe" stampings.

Interesting. Neither of the V belt units that I pulled for my F150 had any kind of brace on the back side, but the brackets are steel. The 460 unit that I pulled for Gary did have a steel brace on the back. I wonder if I need to provide rear support?

What year was that 460? I just received a Saginaw pump and mount for an EFI 460, no brace was included with it and none of the C2 setups I have seen used one. The issue on the Chevy, the belt routing is such that the PS pump has a lot of side load on it.

[Ford F834]

Bill - That looks promising.

As for measuring, I didn't want to get things dirty so spent most of the day cleaning the brackets. I think they came out rather well, but what do you think?

There are a couple of pics below that show the measuring setup with the brackets bolted to the mill table to ensure nothing can move. You can see the inside mic that I used for one set of measurements. And then I used the dial calipers and measured through the hole to the table and subtracted the thickness of the casting at the hole. The two methods gave really close results, like within .006", but I'm showing the caliper #'s as I have more confidence in them.

All measurements from the head mounts to the power steering pump mounts:

• Saginaw:

1:00 Position: 5.593"

3:00 Position: 5.595"

6:00 Position: 5.233"

• C2:

Top Outside: 5.675:

Top Inside: 5.670"

Bottom: 5.668"

If we say that the C2 mounts at 5.670" and the two Saginaw mounts are 5.594", then that says that the Saginaw should mount .076" aft of the C2. Not nearly as much as I expected, so am I thinking incorrectly? However, the difference between the Saginaw mounts are .361".

Here are the pics:

Gary, that is good news for me and looks promising as far as minimal work to make everything line up. Thanks for taking the time to do that!

Bill, Gary's bracket came from a 1990 E350 chassis vehicle.

Edit: are you talking about the amount of wrap causing the side loading? This is the front of the idi: