Thread: Pulling the TBI...then what?

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Originally Posted by kayak

Hmmmm...so I went looking for the needed bolt holes to hook up a the mech. fuel pump on my '89 big block, and lo and behold, they're all there. Even a pushrod access hole (behind that plug).

So, what gives?

Casting date and # match up with the block being an '89 cast. So did they actually slip some of these out in 1-ton trucks? I thought that access for a mech. fuel pump was omitted on 454 blocks after '87 or so.

Kurt

The hole for the push rod is under that plate not the plug ? If it's there .

Originally Posted by tango

The hole for the push rod is under that plate not the plug ? If it's there .

Under the plate huh...two bolts and my great mystery will be answered. Thanks.

Wait, so what's up with that huge plug hole below the plate? Sheeh, my block has more holes in it than Bonnie and Clyde's V8 Ford death car...

BTW, after pulling the throttle body off and showing the pics of it to a fellow forum member who was interested in possibly buying it, he revealed that the tbi was sitting on top of an adapter plate and that my intake was indeed, just a plain old, carburetor manifold.

So at least that issue was solved. Someone along the way, stuck a TBI (with adapter plate) onto my big block...meaning that perhaps, my block wasn't an original TBI motor.

I test fit my quadrajet onto the intake and it snugged up just fine. A few studs on my shopping list and at least that part of my motor test run will be set.

Now to pull that fuel pump block off plate and see what I see...
Kurt

Originally Posted by tango

The hole for the push rod is under that plate not the plug ? If it's there .

Well I pulled the plate and the plug and indeed the pushrod hole was behind the plug itself.
Pictured below are first, the configuration as depicted in Tom Wilson's book, How to Rebuild a Big Block Chevy...

The next picture shows how the holes are lined up on my block.

They look identical to me....

Which means, my '89 block was drilled out for a mech fuel pump.

Now to determine if I actually have a cam lobe to make a mech fuel pump do its thing, then find a fuel pump and pushrod combination that will work.

Thinking of just flipping the motor to one side, sticking a chopstick or wooden spoon handle into the pushrod hole, give the crank a few turns and see if it moves up and down.

If so, I think I can safely assume there is a lobe. If not, back to the electric fuel pump idea.

Kurt
'72 Elky in resto

From the sound of it, somebody put the EFI on an older, carb'ed engine. Good thing for you! Chances are there's a lobe on the cam, too. Sometimes lucky is better than smart, or even good looking!

Originally Posted by R Pope

From the sound of it, somebody put the EFI on an older, carb'ed engine. Good thing for you! Chances are there's a lobe on the cam, too. Sometimes lucky is better than smart, or even good looking!

Ahh, the mystery continues.

Casting # on the block is 14015443, which translates to a 454, 87-90, 2 or 4-bolt, Mark IV, (Truck, Motorhome).

Block casting date is B039 (February 3, x9, or '89 in this instance.

And the old, crusty, intake serial # is 10052952, according to this website is for a 454, 88 Truck, Cast Iron, Oval Port, Lo-Rise, TBI or Q-jet carb.

All this adds up to the block having actually come from a '89 1-ton pickup - what the previous owner told me it had come out of.

Just another one that snuck out of the plant with the fuel pump/pushrod holes drilled.

I love unlocking the past behind a motor, don't you?

Kurt