i am almost done converting my 91 to carb. i put gas in it yesterday and was gonna get the fuel system ready but the manual fuel pump is not pumping. the pump is brand new and pumps by hand fine. the problem is with the rod. when i put the rod in it was pretty tight going in and wouldnt go in the last inch or so. so i tapped it in with a small hammer. figurering the cam would push it out. well its not and its not going back in any further. any idea of how to get it out with out pulling the cam and hitting from that side?

 

You change the cam to one with the pump lobe?
Does that second bolt hole up on the front of the block have a bolt in it? maybe its a tad long touching the rod..?

 

no.... its the stock cam. its a 92 305 tbi that im trying to carb. I thought all cams ran a manuak pump off the number 1 cylinder lobe

 

Not all cams have the fuel pump lobe.

 

Zf6 is on the money. If you had to apply any more force than a light 1 finger touch to.the push rod, there is undoubtably bolt that's a tad too long in the front of the block holding the pushrod in position. Look on the front of the block, there are 2 tapped hole right next to the fuel pump boss, find the one that's parallel.with the path of the push rod.and remove it. The push rod should now be free. Install a shorter bolt so it does not hit the push rod. A longer bolt in that position will hold the pushrod in place while you install the pump, that's why its there. Just be sure to put a bolt in there or it will leak oil

 

I see the two bolt holes there both threaded I see the one thats for the fuel pump but there was no nolt the re to begin with. its just two empty threaded holes.. its a 91 block and came tbi so im thinking they didnt make the hole go all the way through. my guess is its stuck in rhe motor somehow

 

thats odd. Maybe since it was left open it has collected crap ove the years. I have not ever seen a small block that didnot have the hole tapped all the way.

 

I took the water pump off just now and the ac comp. and beacket was already off . I poked my head in there and looked with flash light and its not all the way through. its shiny metal in the back and no a bolt didnt break off in there.

 

figured it out.. I pilled the factory cam out and it doesnt hace a lobe for a mechanical pump. so now goes in a 480 lift cam

 

Just a note here, my block from an 87, does not have a through hole either. It appears the factory made a change there at sometime.

Any one else know anything about this?

 

Those holes were onced used for motor mounts, and IIRC it was hit or miss if the newer blocks had that hole tapped or not. I was told that some go all the way thru to the fuel pump push rod and some don't. A friend of mine built up a 71 4 bolt main block and had to put a bolt in there to keep oil from leaking out, but on my 68 350 block, I didn't have to do anything.

 

Mine is there and tapped, just not through.
I was planning on installing a roller tip pushrod in there.
Wondering if i can drill and tap, without screwing up the existing threads.
Because they're the size i need. I can't go larger.

 

Use the right size drill bit for the size bolt, should be 3/8-16, be very careful and you should be ok. You will need to clean the pushrod bore very well afterward so you. Don't have any steel shavings getting into the engine

 

Sounds reasonable enough. How much material do you suppose there is to drill through?
Do yourself a favour and use a transfer punch of the appropriate size to make a index in the casting for your drill bit. That way you can start with something a little smaller than the actual drill size needed which is 5/16ths (it should the same for the transfer punch too). The index mark you make via the transfer punch will keep you centered in the tapped hole while you drill progressively larger.
Stuff the inside of the push rod bore with a small piece of shop towel to help prevent the shavings form getting up inside.

 

I myust have missed something. Why do you need to drill and tap that hole all the way through? Most people wish that it WASN'T tapped all the way through because they often forget to put a bolt in it to prevent oil from spraying out under heavy throttle.

Yes, you can temporarily put a longer bolt in it to prevent the pushrod from dropping down as you install the fuel pump but that's FAR from the only way of accomplishing that job.

 

In johnod's case, he's wanting to install a roller tip fuel pump pushrod. It's held square to the cam via a bolt that's installed in the hole in question.

 

Oh, I see. Never used one of them before. I can't say I've had any reason to use antything other than a stock one. To each his own.

 

We're trying to prevent this from happening.

 

That's really unlikely with a diaphragm pump. You'd only see that with a piston pump like what would be on a racing mechanical FI setup.

 

That's about 40 000 miles worth of wear on a retro fit roller cam. The first 2/3 rds of it's life, it operated a Carter high volume pump. Nothing special. Over the years the fuel pressure (sustained WOT) started going away. A switch to an Edelbrock pump supplied better results but they soon went away to nothing. This cam eccentric is what's left.
With the roller, I always full synthetic and I blame it on the reduced oil additive levels. A ceramic or similar tipped push rod would have spared the cam lobe but would eventually erode to the point of needing replacement.

 

I am wondering if there are different fuel pumps for 350 Chevy engines. I have a motor that ran fine when I pulled it. But somewhere along the line the pump came up missing. So I purchased a stock style fuel pump but it won't pump gas jus a little then nothing. I was wondering if one may have a longer pump arm than others.

 

No, they're pretty much all the same as far as that goes.

What car is this motor in? Same car as before?

 

No not the same it was a 6 cylinder fuel injection but now is old school 350 but won't deliver fuel after first initial start up. It primes as you turn the key on but will not deliver fuel after that . I can drive it down the road but stalls out then you have to cycle ignition to get gas again. I'm trying to run the original fuel pump

 

Yes they (mechanical fuel pumps) are all pretty much the same (in regard to arm length) as far as that (arm length) goes.

"6-cyl fuel injection" has NOTHING WHATSOEVER to do with anything about "arm length" of mechanical fuel pumps, on its own.

"Prime" is an electric fuel pump problem, not a mechanical fuel pump one. This post does not belong in this thread which is about block-mounted mechanical fuel pumps. Start your own. Although, it sounds like you still have the in-tank electric pump, but it's not wired/controlled right, and your additional unnecessary mechanical pump can't "suck" fuel through the obstruction of the improperly managed electric one.