So on my 84 z28 i got a mechanical fuel pump, I already removed the old one and when I go to put the new one I am not sure whether the little lever has to compress against the rod inside the housing??pease help, thanks.


and the rod is not pointed out as in pointing out the hole of the housing if that makes sense, its more horizontal

 

lever presses against the pushrod. if you can rotate the engine over, SLOWLY, youll feel the pushrod move up when its off the cam lobe. there is a bolt you can take out in the front of the block, it goes right to the pushrod. i usually use a 3 inch bolt to TEMPORARILY hold the pushrod up in its bore, while i install the fuelpump. dont forget to re-install the original bolt or youll puke oil everywhere.

 

do I necessarily have to make the push rod go up or can I just compress the lever against the rod and screw on the bolt of the pump back on?thanks.

 

its best to get the pushrod up first. i cant remember,..duh,...i think at number1 tdc the cam lobe is away from the pushrod. i could be wrong? youll feel it. you can also have a friend use a screwdriver to hold the pushrod up through the hole i told you about.

 

If you want to do it the hard way

 

alright ima try turning voer then engine but should i turn it over manually or with the key in the ignition?

 

id do it by hand. put a big pipe on the end of your ratchet and slowly turn the engine. youll be doing yourself a favor by getting that pushrod up in the bore.

 

alright ima give it a shot,,,thank you again!

 

would you recommend putting blakc rtc on the gasket?

 

your welcome. yes, i use rtv silicone on the gaskets. you dont wanna leak oil from there. once you do it right, its easy. if i was there wede be done by now. lol. how are you making out with it?

 

liek ive said i just need to put the new pump back on, ive had this on my to do list for the past 2 months i just havents gotten to it...and i know this is off topic but do you know where i can get the firing order for the car because i thiink i yanked on the sparkplugs cables by accident and accidentally mixed them up...oppps

 

Your #1 wire may not be in same place on the dist cap as shown above , guys move them around
Locate where # 1 wire ACTUALLY is on the cap then connect other wires in the order shown in the diagram

 

and thank so much for the help u guys...i just finished installing the pump his afternoon...it worked like a charm!!

 

I'm needing to change my mechanical fuel pump, as well. I've got the old one out. I can't see up in the hole, but it does feel like a pushrod in there. I have rotated the crank several times to put it at varying spots including TDC, and I can't seem to get that pushrod to move. Any suggestions or ideas? Also, where is this hole in the front of the block that I can put a screw in to temporarily hold the pushrod? This thing is becoming pretty frustrating.

 

If the push rod is up in there, it's OK; if it's not all the way, it'll make it a bit tougher to get the bolts in, but by no means impossible.

You can use a bolt in this hole to secure the rod. Be sure to put the original bolt back, with a drop of sealer on the threads.

 

Thanks. That's where I thought it would be. Those holes appear to be for the air pump bracket bolts. Now, is it normal for the pushrod to be all the way down and feel like it doesn't want to move upward? I mean, I can't get this pushrod to move at all.

 

It should slide fairly easily; after all, the fuel pump's return spring must NOT ONLY push the fuel toward the carb, BUT ALSO push that thing back up. Can't be ALL THAT hard to slide.

Rotate the engine ¼ turn and see if it changes. Eventually it should move, either in or out from where it is, about ¼" or so.

Yes those holes are indeed for the AIR pump bracket. On 55-57 cars and well up into the 60s in trucks, they were actually the motor mounts.

 

I've got the air pump pulled out of the way and the bracket removed. It feels like I can turn the pushrod radially with my fingers, so I'm assuming that the pushrod isn't seized or stuck. I'm going to rotate the crank like you said and see what happens.

 

Finally! I got the pushrod loose and moving. I can push it up, now. I had to play and fanagle with it for a while with each turn of the crank, but it finally moved upward, freely. It must have gotten somewhat lodged in place when I took the old pump out. Anyway, I'm going to the hardware store to get a three inch bolt to hold the pushrod in place. It's getting late, here, so it'll probably be tomorrow before I get it all back together.

 

Sounds like it's well on its way... like you've got it figured out and licked.

 

Got the fuel pump installed. There was a spacer plate (? guess that's what you call it) between the pump and the block which also covers the bottom half of the fuel pump hole in the block. There are two small bolts at the bottom of the plate. It became apparent that the bottom of the pushrod was resting it against that plate with the old pump out. Had to take that plate off. Figured I should be able to actually remove the pushrod if I did. Once I took the plate off, I had direct access to the pushrod. Dabbed some grease on the cam end and shoved it back in there. Got a gasket for the plate and installed the pump. (It was pretty easy once I determined that spacer plate had to come off.) Pushrod stayed in place long enough for me to get it all back together. This was the first time that I've dealt with a Chevy, so it was a learning experience. (I'm a Ford man, myself.) Anyway, the pump works. It sucked the gas from the tank to the pump, but then, the two rubber lines started leaking. The car had been sitting up for better than 13 years. I actually got it started about 6 years back. Ran long enough for me to get some gas in it. After that, nothing. Finally got around to looking at it and decided to restore the car. I figure that, since ethanol is now in all gasoline, it ruined the diaphragm in the old pump. That's why I couldn't get it running again. Apparently, the ethanol also ate up the rubber hoses because gas was leaking out of both, plus the hoses felt pretty spongy. Going to get a couple of 6' lengths of each hose and replace those. I'll use some regular screw clamps instead of those factory clamps. I've got the battery back on the charger, and I'm going to change those hoses probably in the next day or two. I'm just hoping now that the carburetor isn't shot because of that ethanol. (Does anyone know if there are rubber diaphragms in those carbs?)

 

Update: Was curious to see if gas was actually making it up to the carb, so I pulled the line at the carb. I also took out the fuel filter. Gas was, in fact, getting to the carb, now. However, the fitting that holds the fuel filter seemed somewhat plugged. Nothing looked unusual during the inspection. It was just hard to blow through. After a few attempts to blow through it, it miraculously opened up, and I could blow through it, freely. Reinstalled the filter and reconnected the line. Decided to see if it would fire up even with the two hoses at the fuel pump dripping. That sucker fired right up. Let it run for about 10-15 seconds and shut it down. Sounded pretty good for sitting there all those years. I need to replace those rubber hoses, anyway, not only because of the dripping, but the new pump connections were pointing in a different direction than the old one, and the hoses are somewhat short not really making that great of a connection. I could probably just replace the clamps, but I'm going to replace the hoses, anyway. In any case, it looks very promising, now. Hopefully, I'll have it back on the streets before too much longer. I need to get a set of tires for it, first, as the old ones dry-rotted from sitting there. Also, there's a fair amount of body work to be done. Anyway, thanks for the suggestions and the pic. This board has been a real help.