Fuel pump Vacuum Cover MIA

[madmike]

I rebuilt the fuel pump when finishing my restoration and with about 20 miles on the engine noticed a new noise that I chased for a while until I looked underneath with a drop light. The bottom cover (vacuum) to the pump is gone. I have no idea where I lost it. Although I have been known to forget to tighten bolts before I really do not believe that was the case here. It is possible I did not snug it enough since only one bolt holds the cover in place and I did not use thread locker.

BTW, this situation makes quite a bit of noise. I was beginning to think the engine was going to grenade.

I would like to know if anyone believes pressure could have blown the cover off before I simply look for a replacement. Speaking of which, the model is the dual pump BK series. If anyone has a junk pump but good cover and screw I would be interested in purchasing same. Can probably make or find a gasket. Ideas and comments appreciated, even if they hurt a little.

[oilleaker1]

The cork gasket supplied with the kit will crush and take a set which allows the cover to get loose. You have to re-snug the center bolt. I kept running out of gas on my Civi pickup's double acting pump until I discovered the air leak in the fuel system was loose covers! John

[madmike]

Thanks John. That is a likely possibility. I believe I will use some thread locker too. Not the red hard setting but the blue type which still allows removal without too much problem.

[RICKG]

Mike I've got a solid AC4260 core.
I was asking $30.00 + ship on an earlier post and still have it.
Let me know if you want it.

Further investigation tells me the AC 4260 is type CU & CY.
Looks similar to type BK pic found in downloads.
Don't know if Vac cover is same/same..

[timjuhl]

Mike, A BIG thank you for your post. After reading your comments I went out and checked the bolt on my fuel pump and although it wasn't loose enough to turn by hand, it wasn't "snug." After carefully tightening it, I took the jeep for a test drive and discovered that I'd solved another mystery.

Recently when I shut the engine down in the garage I'd hear a buzz or hiss for a few seconds after the engine quit. After tightening the fuel pump cap the noise disappeared.

I'm thinking of drilling the head of the bolt and securing it with safety wire.

Thanks!

Tim

[madmike]

Your welcome Tim...but all things considered I'd rather be driving this Jeep than repairing my bad assembly work.

No one mentioned if this cover could be working under pressure instead of vacuum and when the engine is running it does sound like a wheezing machine. Probably just me leaving the cover loose. This pump was on the Jeep for a long time before I got my hands on it.

I have one coming from John at Midwest. He offered one for 10 bucks so I thought I would start there. So thanks anyway Rick but if there is something wrong with the bolt threads in the housing, I may be contacting you.

[wesk]

Does the bolt (By itself) thread snugly into the housing or is it loose and rocking about? If loose and rocking about you should consider installing a new threaded insert.

[madmike]

The bolt was snug on the threads and I applied a little bit of blue thread locker when I put the NOS cover in place. After a bit of driving I will check the bolt again. When tightening the new cover I noticed a bit of flex in the metal. That might have stopped me when placing the original cover in place for fear of collapsing it. Just guessing here but on the new cover I am certain I tightened it more than the other one.

Still no sign of the old cover and I did not drive it out of the garage after Camp Delta. That's probably where it came off.