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Discussion Starter #1
Kinda new here. I have a 48 Ford F1 with a 4BT. Guy I bought it off of did a great job. I'm doing some unfinished work.

I found out that I should have the brace installed to support the stackup. I have the older style aluminum casting that has the sharp corners prone to cracking.

The issue I have is the 4BT uses the 4 cylinder P7100 which is lighter and shorter than a 6BT inj pump.

The existing inj pump to block bracket on my 4BT is thinner and doesn't have the extra length at the bottom with a threaded hole to accept the brace.

I purchased a used 6BT brace assy but discovered the 6BT brace inj pump to block won't work.

I'm wondering with all of the different industrial applications out there if this particular engine ever had the vacuum pump/power steering pump stackup and if there was a brace for it?

Here is the stackup.
20190920_160722.jpg

Here is the 4BT with the stock inj pump to block bracket
20190927_165851.jpg

I removed that 4BT bracket to compare to the 6BT bracket.
The two holes that bolt to the block are the same geometry but as you can see the beige (4BT) on the left bolts to the shorter P7100 differently up top. There are thickness differences too.
20190927_165532.jpg 20190927_165547.jpg

If there are the correct parts I would like to purchase them. Otherwise I will have to extend the existing bracket at the bottom and install the small angle bracket to transfer the hole location to it and drill and tap it.

The other problem is the dip stick comes out right exactly where the brace is. What a pain.
20190927_165917.jpg


20190901_181400.jpg
 

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You are finding an issue common with trying to use the vacuum/power steering combo in a 4bt. That unit never came on a 4bt. 4bt vacuum pumps were mostly belt driven. One possible solution you mentioned would be weld an extension onto the P pump support for the 4bt. You could use the 6bt bracket to get the location correct. Would also want to verify that the little angle brace will hit the right spot on the combo. Another option would be make a support brace mounted to the 2 bolts on the oil filler block off. Looks like this is going to be one super nice ride.
 

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One way to go is to add an additional electric powered vacuum pump. Or what I did was took the alternator vacuum pump from the previous motor setup I had.
You can find a new alternator with a vacuum pump on the back on eBay or your favorite online site.
I found it searching under Isuzu NPR alternator with vacuum pump. I found it $147 but can’t figure out how to post the link.
Only thing is you will need an oil line and an oil return line fabricated with a possible new alternator bracket to make it all work with your current set up. Hope this helps. I’m current trying to fabricate a good oil return line for my alternator driven vacuum pump. Any suggestions would be great.


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Here is the 4BT with the stock inj pump to block bracket
View attachment 124481
Referencing the above picture
Brace for vacuum - power steering pump.JPG
This brace has over 70,000 miles and 37 states so far.

I started with some angle iron and slowly cut away a curved side to "cradle the flange.

All the holes are oversize, that way, the parts can be assembled and the bolts slowly tightened up, pulling everything into alignment - the goal is not to have strain from misalignment on the assembly.

2 more pictures

PS bracket - side view.JPG

PS pump bracket - bottom view.JPG
 

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Discussion Starter #5
Referencing the above picture
View attachment 124503
This brace has over 70,000 miles and 37 states so far.

I started with some angle iron and slowly cut away a curved side to "cradle the flange.

All the holes are oversize, that way, the parts can be assembled and the bolts slowly tightened up, pulling everything into alignment - the goal is not to have strain from misalignment on the assembly.

2 more pictures

View attachment 124505

View attachment 124507
That is perfect. That's the way I'm going. Thanks all.
For some reason I didn't get email notifications on these posts. I'll check my settings.
 
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