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Discussion Starter #1
I have taking apart a few Marelli, but this is first JF4 …….. so a question.

The pin holding the oil pump coupling does appear to want to come out easily, as it does with Marelli. Are both ends of this pin peened so it has to be drilled out?
 

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Hydraulic press Carl, with a hardened pusher. The pin is loose in the main shaft and an interference fit in the driven hub. When I'm lucky I can knock them out with a hardened punch with a "V" block, but that can get messy if the hub rotates in the "V" block. With my press, I just grab the hub in a machinists vice and press it out. Once out you CAN reduce the interference fit of the hardened pin slightly for easier re-assembly.
 

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Gordo, I believe it is one way in and one way out... It is a tapered pin as I surmise ... U. Even when right.. it can be a test. The peened side is not the drive out side.
 

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Possibly why the "V" block and hard punch fails...
I have a pin here with dimples on both ends. Digital caliper shows no taper....
 

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Digital caliper shows no taper....
Agree. I don't think those pins are tapered. But they can get pretty locked in place with corrosion & crud.

Hydraulic press Carl, with a hardened pusher.
It never fails to amaze me how much easier it is to disassemble interference fit parts with a press than it is with a hammer.
 

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Discussion Starter #7
The pin is out! Bosch really didn't want these pins to ever come out. It was a very, very tight fit holding it in; not rust. Not having the right size V-block, I made a stand from scrape aluminum. I used a 1" hole-saw and drilled a hole through the stand to "catch" the pin. The 1" was a little too large, so used 0.010 shim stock to fill the gap. I first attempted to do as Gordon suggested …. my 20-ton press. But I could not get the press to not go sideways attempting to push a small length of oil-hardened steel as my "pusher" …. which promptly bent. So I went with the alternative of "shocking it out" with a Starrett pin-punch and hammer.

Then pin is made of really good steel. Even with all the pounding to get it out, it still looks good.
 

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I LIKE your holding fixture!
 

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Chase beat me to the post. Yes, the pin has a safety feature of a spring that winds around the base to make sure that pin doesn't come out as the shaft rotates. I only did this once with a good hammer and steel punch. It did come out but it was some effort as you have found out.
 

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I restore quite a few Bosch JF-4's and it seems Bosch used that interference fit pin on all their Alfa application units. With a correct holding fixture, the pin does come out. With anything less, you are in for FUN!
 

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Discussion Starter #13 (Edited)
Starting the evaluation, between playing handyman for daughter, …… I don't know how well these photos of cam will appear. But does this look like just normal 50 years of wear? Couple of scratches and some loss of surface hardening. Measuring cam tips as best I can, measuring diameter of a pair, turning 90 degrees and measuring the other pair …… they are within 0.001".
 

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