Ac 4693 Fuel Pump Pillow

I rebuilt a unit with a Walcks/Then & Now kit. Lubricated the pillow before install, tested in the drive way, heard a light tap, stopped engine, pulled the fuel pump and the pillow had sheared off at the mounts.

Now I have to drain the pan, hoping it passes or else pull the whole pan. Any idea why this occurred? This is the factory unit my 61' would have left the factory with, I bench tested and lubricated the pillow liberally with engine assembly lube.

Only difference is, I do have a mild Isky grind but I assume they do not touch the lobe the fuel pump rides on.

Any idea other than eBay for a similar unit I can pilfer the pillow from so I can replace, bench test and sell to recoup my investment.

 

I restore pumps. Never heard of a "pillow".

 

the sliding curved end, I saw it elsewhere referred to as a "pillow"

 

I’ve always called that piece a “slipper”. No help on an alternative source for another one. I think you’re going to have to drop the pan. The chances of both halves flushing out with draining the oil is pretty slim.
-Donny

 

I agree, better safe than sorry. I still have a slight leak to address anyway. Stumped why it sheared off, worked as designed in the vise. Unless it has to do with the "spacer" that's mentioned on various Jeep boards, some used it, some didn't, not seeing it mentioned in the manual either, parts manual Page 60 makes mention, but no "X" to denote model.

Back to the old AC single action and Marinco electric wipers.

 

After what I went through with an engine rebuild of a rebuild by the PO, and I have this small pesky leak, it will give me a peace of mind to fish it all out and inspect.

 

Had a 57 CJ where that foot fell off and I found it in the bottom of the oil pan. Just stopped running. I was out on the farm and drove it back to the house with a plastic jug strapped to the windshield. The fuel gravity fed to the carb. well enough to get it home.
Funny it didn't hit anything.

 

I read a few reports on here where the same occurred. Guessing just a weak design that's stressed over time? I got hit with a wave of nostalgia so reverted back to vacuum wipers, rebuilt this unit. Cutting my losses, back to electric wipers.

I could run something like this but unsure how much vacuum the Trico units need and can hold. https://www.amazon.com/Vacuum-Pump-...361623&sprefix=12v+vacuum+pump,aps,243&sr=8-3

 

There is no physical possibility of a vacuum greater than atmospheric pressure. About (negative) 15 psi maximum.

 

The bracket used to secure the "shoe" is notoriously flimsy. Unsuspecting first-time rebuilders usually break it off. It will take a good amount of patience and labor to attempt to straighten and recurve the lips. Most of the time it ends in failure of the bracket. The shoes are unobtanium.

 

Think worthwhile to source a sturdy 12v vacuum pump to run the Trico wipers or just revert back to electric?

 

I was hoping to find a similar unit with the shoe still intact on the arm and replace it, possible? Hate to trash it, has an $80 rebuild kit installed not to mention the cost of the unit.

 

Be patient. It will take a while unless you get very lucky.

 

Another option is to continue using the intake manifold vacuum, as OEM did, and perhaps add a reservoir tank. Common on many cars in the day.

 

As PeteLL said, be sure to get a vacuum reservoir for your system, otherwise, you encounter wiper stoppage under full throttle conditions. Good luck!

 

You may be referencing one of my old post.
I may have referred to it as a sliding pillow block ?
In truth it very much resembles the early type journal “blocks” that were used on early train cars.
Mimics them in basic design, construction material used and via the oil bath type lubrication.
On the 4693 this “sliding journal block” can easily become dislodged if the pump stroke is not properly regulated.
The pump stroke is regulated via the required fuel pump mounting spacer.
I find the AC 4693 to be an excellent dual action pump.

 

If you live in rainy hill country like the PNW, even a reservior doesn't last long.

 

Vacuum wipers never really worked well on any of the vehicles I had with them, reservoir or not. If you were pulling a long hill, you had to let up on the throttle to clear the windshield. The original intermittent wiper system. An electric vacuum pump is probably the only means where those wiper motors will function continuously. If one is into the factory "look", that would be the way to go.