FINALLY installing vortec 350. Mechanical fuel pump?

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guitarfreak235

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Finally installing the vortec. Got the edlebrock 2116 intake for vortec heads finally installed. Yea its been years. 700r4 went out yesterday so its time to replace or rebuild that aswell.

I know that vortecs dont necessarilly come with the lobe on the cam to drive the mechanical fuel pump, but mine has the provision to mount one and has the hole drilled for the pin. Is it ok to run the electric pump thru the mechanical one if the mechanical isnt being driven?



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Maybe a borescope would be helpful in determining this. If you had a fuel pump pushrod, you could see if pushes out when you turn the engine over. Just make sure it’s recoverable with a magnet. I don’t think it’s a good idea to run gas through an unmoving pump. I don’t have anything to back that up, but I feel like intentional resistance (a regulator) is the only way to go about that.
 

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Just curious why you’d want to do that. It’d just be tha
Finally installing the vortec. Got the edlebrock 2116 intake for vortec heads finally installed. Yea its been years. 700r4 went out yesterday so its time to replace or rebuild that aswell.

I know that vortecs dont necessarilly come with the lobe on the cam to drive the mechanical fuel pump, but mine has the provision to mount one and has the hole drilled for the pin. Is it ok to run the electric pump thru the mechanical one if the mechanical isnt being driven?



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thats odd. My Vortec looks like it does, but it doesn’t go through.
 

guitarfreak235

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So that i dont have to get a new fuel line or adapters or whatever. I figured id leave the hard line from the carb to the pump since i am putting an electric pump inline near the tank. Other wise i need an apapter to the hard line or get a new hose to go to the carb. I had just heard of people doubling these up as a "backup" so i figured it might would still run with the pump not operating with a one way valve or something.
Just curious why you’d want to do that. It’d just be tha

thats odd. My Vortec looks like it does, but it doesn’t go through.

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guitarfreak235

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Ive thought about doing this, but if there is no lobe would it be possible for the pin to go too far and fall inside the motor?
Maybe a borescope would be helpful in determining this. If you had a fuel pump pushrod, you could see if pushes out when you turn the engine over. Just make sure it’s recoverable with a magnet. I don’t think it’s a good idea to run gas through an unmoving pump. I don’t have anything to back that up, but I feel like intentional resistance (a regulator) is the only way to go about that.

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So that i dont have to get a new fuel line or adapters or whatever. I figured id leave the hard line from the carb to the pump since i am putting an electric pump inline near the tank. Other wise i need an apapter to the hard line or get a new hose to go to the carb. I had just heard of people doubling these up as a "backup" so i figured it might would still run with the pump not operating with a one way valve or something.

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I didn’t mean to send that first part. It sounded bad. Hope I didn’t sound like a smart ass. I truly was just curious.
 

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the mech pump may block flow from the electrical pump
 

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Ive thought about doing this, but if there is no lobe would it be possible for the pin to go too far and fall inside the motor?


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That’s a good question, and I could see that as a remote possibility without a camshaft eccentric pushing out on it. Are you sure there’s an opening there? My TBI block has the pump flange cast into the block, but there’s no hole for the pushrod. The borescope option is still on the table. You can get one that hooks to your laptop for $12-$20. Hell, pumps are cheap. You could put it all together and see what happens. I would do my best to go with the mechanical pump if you’re set up for one.
 

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@HotRodPC ?
What yall think aboit checking for the cam lobe?

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guitarfreak235

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That’s a good question, and I could see that as a remote possibility without a camshaft eccentric pushing out on it. Are you sure there’s an opening there? My TBI block has the pump flange cast into the block, but there’s no hole for the pushrod. The borescope option is still on the table. You can get one that hooks to your laptop for $12-$20. Hell, pumps are cheap. You could put it all together and see what happens. I would do my best to go with the mechanical pump if you’re set up for one.

Just saw your post. Might hook it up and see like u said. Id preffer mechanical myself as it was originally that way and the only thing holding me back is the cam lobe.

But again 12-20 is cheap i might need to invest in that.

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bucket

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If you do in fact have the hole for the pushrod, just put it into place and rotate the engine over. Or if the intake is off, take a peak in the lifter valley, maybe it can be seen. I don't remember if my vortec motors have a pump lobe.
 

guitarfreak235

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If you do in fact have the hole for the pushrod, just put it into place and rotate the engine over. Or if the intake is off, take a peak in the lifter valley, maybe it can be seen. I don't remember if my vortec motors have a pump lobe.
Dont think id have an issue with the rod going in too far if there is no lobe?

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I have a 96 vortec short block that is factory drilled for a mech pump. The pan is off so I can check to see if the cam has a lobe if this will help you. I will be going to my shop later today and report back when I get back home.
 
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