Oh dear...slight setback

[speedo]

Inching closer to getting the engine in my 72 targa running after 25 years. After ripping out a "cheeseball" alarm and stereo installation, replacing a rusty drivers side battery box, installing a new Miata (Deltek) AGM battery, AND rebuilding my 001 MFI fuel pump...I wanted to see if I could get my new battery to power my rebuilt fuel pump. I turned the key in the ignition and my gauges jumped...looks good so far! Turned the key another notch and heard the pump happily spin up...for a few seconds and then it made an awful gurgle-y noise and I smelled varnish. Quickly shut things down and pulled the gas tank fuel sender. Peyew...yuck.
There was a couple inches of nasty rusty looking (former) gas in the tank. Dammit!
I pulled the tank and drained it. Removed the fittings and noted that the filter screen had almost disintegrated. And there was loose crust in the tank. A week later, tank is de-rusted,treated and sealed using POR 15 gas tank kit, and painted. I rebuilt the filter screen.




Re-installed tank with a rebuilt fuel sender, rubber coupler and added fresh fuel.
Keyed the ignition to hear the fuel pump and NADA. My guess is that I killed it with the crap that I force-fed it from the gas tank. Bummer. Guess I need to get the rear up in the air and remove the fuel pump AGAIN and take it back apart. My hope is that the crap I fed it was large enough to clog the impeller, but too large to get into the pump chassis itself? Maybe I just disassemble the top of the pump and clean it up...bench test it? Thoughts?

[timmy2]

Did you plug up the swirl pot in the tank with the POR15?

[speedo]

Originally Posted by timmy2

Did you plug up the swirl pot in the tank with the POR15?

I hope not as weren't these specific to CIS engines? My 1972 is MFI and from what I can tell looking into the tank...there is nothing in there. Used to be a lot of debris and now it is very clean and sealed.

[timmy2]

Oops, for some reason I was thinking ‘74...
Never mind.

[manbridge 74]

No swirl pot on these.

I like to spin these up on bench with screws just lightly touching as all parts need to “self-adjust” to a free position so to say.

Last one I took apart had no pre-screen either and a large piece of gas tank sealer was jamming the impeller. Removed it and it’s been operating okay for years now....

[speedo]

[QUOTE
I like to spin these up on bench with screws just lightly touching as all parts need to “self-adjust” to a free position so to say.
Last one I took apart had no pre-screen either and a large piece of gas tank sealer was jamming the impeller. Removed it and it’s been operating okay for years now....[/QUOTE]

Cross my fingers...

[gomezoneill]

How about some photos of the 72 MFI system components?

[DanielDudley]

Reverse the leads and try to spin it backwards. If that doesn't work, take it out and soak it in ATF for a couple of days.

[speedo]

So I raised the rear of the car and wrestled the fuel pump out of the cradle. Bench tested and nada. Took it apart and some "minor" debris was evident. But the impeller probably didn't want any debris, so I cleaned it up and tested it and it ran fine. I ran it long enough to eject the nasty crap I "water-boarded" it with. I installed a brand new O ring and sealed it back up and re-tested it...sounds fine. Hardest part of this endeavor was getting it removed and re-installed. Had to do it on the floor with jackstands and a mirror. Once installed, I keyed the ignition and it spun up nicely. Would have tried to start the 72 but weather outside was miserable and I didn't want to try to start it in a closed garage. It was raining and 40 degrees F outside. I'll do it on a day when I can open the garage door. Always exciting to start an engine that hasn't run in 25 years.

[speedo]

The beast roared to life tonight after 25 years of dormancy. And of course 25 years of mouse crap and seed shells got burped out of the exhaust. Smoked a bit but that was to be expected. The quick "top end" on the fuel pump did the trick. If anyone needs the four carb/MFI Bosch rebuild O ring sets , I have a few extra sets for $10 apiece till they are gone.

Speedo

[RSBob]

Congratulations and well done!

[manbridge 74]

Great.

Last two engines I’ve done had rodent debris piled up around cylinders 3 & 6 which killed the exhaust valve guides.

I recently installed a MFI pump from Porsche in a 69 911E. There were reports of these being made in China but I was glad to see it had made in Germany on it. Even if the components were made somewhere else and it’s only assembled in Germany, I’m hoping they are on top of quality control. It looks fairly identical to OE Bosch, the length might be a few millimeters longer on the motor end. The OE pumps are robust and have long lives on regularly driven cars so good job on reviving it...

[tdw28210]

Congrats on the revival!!!