Fuel pump pushrod?

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oldjunk

oldjunk

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In the middle of changing the mechanical fuel pump on my 340. Having trouble locating the pushrod that runs the pump. Shouldn't I be able to push up on the rod and slide the pump arm underneath? I slid the new pump in and it seems I have to push up on the pump with a good bit of force to get the bolts to line up...is this all I need to do? Any help would be greatly appreciated. First time doing this. Thanks guys.
 
oldjunk said:
In the middle of changing the mechanical fuel pump on my 340. Having trouble locating the pushrod that runs the pump. Shouldn't I be able to push up on the rod and slide the pump arm underneath? I slid the new pump in and it seems I have to push up on the pump with a good bit of force to get the bolts to line up...is this all I need to do? Any help would be greatly appreciated. First time doing this. Thanks guys.
Click to expand...

The pump arm is riding on the eccentric and is probably on the high side. Just hand crank the engine over a half turn and if that doesn't do it crank about another half turn and it should go almost flush at some point. Reason for up to a full turn is the cam turns at half crank speed.
 

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OldmanRick said:
The pump arm is riding on the eccentric and is probably on the high side. Just hand crank the engine over a half turn and if that doesn't do it crank about another half turn and it should go almost flush at some point. Reason for up to a full turn is the cam turns at half crank speed.
Click to expand...

Thanks for the response Rick. So I can just put the pump in, push up on the pump and tighten down? Or do what you said and turn the motor over by hand to rotate the eccentric flush?

Another thing that concerns me is the timing chain. I stuck my finger in there and it feels very slack. Is this a sign it needs to be changed?
 
oldjunk said:
Thanks for the response Rick. So I can just put the pump in, push up on the pump and tighten down? Or do what you said and turn the motor over by hand to rotate the eccentric flush?
Click to expand...

Either way should work, but if you've got tension on the arm just be sure to tighten each bolt a little at a time to bring it flush.
 
Another thing that concerns me is the timing chain. I stuck my finger in there and it feels very slack. Is this a sign it needs to be changed?[/QUOTE]

The chain may be tight on the other side and would make it feel a little loose on that side. May or may not be a issue. Do you know how many miles are on it or if it has ever been changed before?
 
oldjunk said:
In the middle of changing the mechanical fuel pump on my 340. Having trouble locating the pushrod that runs the pump. Shouldn't I be able to push up on the rod and slide the pump arm underneath? I slid the new pump in and it seems I have to push up on the pump with a good bit of force to get the bolts to line up...is this all I need to do? Any help would be greatly appreciated. First time doing this. Thanks guys.
Click to expand...

Rick is the man and has you hooked up.

The fuel pump pushrod is a GM thing.
 
The fuel pump pushrod is a GM thing.[/QUOTE]

That's the first thing that came into my mind too:smile:
 
Thanks guys for helping a :newb:. Yeah, I was on youtube and saw a guy changing the pump. It was a chevy. The gasket for the pump was a pita to get off. I used some permatex gasket remover that didnt do anything but remove the engine paint :angry5:. I ended up scraping most of it off with my fingernail since I couldn't get my scraper down there. This was the worst part of the entire job. You guys rock.:prayer:
 
oldjunk said:
Thanks guys for helping a :newb:. Yeah, I was on youtube and saw a guy changing the pump. It was a chevy. The gasket for the pump was a pita to get off. I used some permatex gasket remover that didnt do anything but remove the engine paint :angry5:. I ended up scraping most of it off with my fingernail since I couldn't get my scraper down there. This was the worst part of the entire job. You guys rock.:prayer:
Click to expand...

I here ya' on old gasket removal. We've all been there but it's gotta be done:smile:. Glad it's working out for you.
As far as the chain goes, if you think it's old or getting loose you should probably prepare at some point in the future to replace it. Also not a bad time to put a new water pump on, if need be, since you'll have it apart anyway.
 
OldmanRick said:
I here ya' on old gasket removal. We've all been there but it's gotta be done:smile:. Glad it's working out for you.
As far as the chain goes, if you think it's old or getting loose you should probably prepare at some point in the future to replace it. Also not a bad time to put a new water pump on, if need be, since you'll have it apart anyway.
Click to expand...

Rick,
I bought the car without knowing when it was restored. The motor is original to car with some minor performance upgrades. It has an aftermarket cam, but it's unknown to me. It runs good, but I'm thinking of tearing into it in the near future. When I do, I'll be sure to change the cam, chain, and water pump. Who knows, I might just do an entire rebuild and learn something in the process. Thanks again for your help!:burnout:
 
Your welcome. I'm without anything right now so i'm living thru you guys. Enjoy it and have fun, that's what it's all about.
 
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