need help with holley 750 d.p

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340plot

340plot

the bushy bush
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i have a 750 d.p on my 340, and it is leaking fuel out of a few spots. it has sat for a few years, only started once in a while.
i was asking questions on here for the past few days, and someone told me that it would be cheaper to just rebuild the one i have.
but it is leaking fuel out of the side, where the linkage comes out for the gas pedal. i was wondering if the rebuild kit comes with all these seals??
is it hard to do the work myself. i have never really messed with one before

any suggestions guys????????????????????????
 
there is more than one kit,the more complete it has everything....they are not difficult to rebuild.the kit should come with detailed instructions.
 
where do i get the complete kit? and do you have any clue what they run?????????
 
It sounds as though it is flooding and therefore leaking out of the throtle shafts. But you need to check the shafts for excessive play where they run thru the base plate.
 
340plot said:
i have a 750 d.p on my 340, and it is leaking fuel out of a few spots. it has sat for a few years, only started once in a while.
i was asking questions on here for the past few days, and someone told me that it would be cheaper to just rebuild the one i have.
but it is leaking fuel out of the side, where the linkage comes out for the gas pedal. i was wondering if the rebuild kit comes with all these seals??
is it hard to do the work myself. i have never really messed with one before

any suggestions guys????????????????????????
Click to expand...

Rebuild kits do not generally come with thottle plate bushings and even if they did, you can't easily replace them due to the staked throttle plate screws. These bushings going bad is very common on older used Holleys due to a myriad of issues including but not limited to warped base plate from overtightening, improper springs and mis-aligned throttle linkage, etc. New base plates (called throttle bodies) are availible complete from Quick Fuel and are very high quality. They run about 180 bucks or less.

You still shouldn't have fuel running out of them and I'm guessing that fuel is running out of the boosters due to mis-adjusted float level, bad needles and seats, sunk/stuck float, dirty fuel, etc.

Ideally, if it was my carb, I'd replace the throttle body and rebuild it the carb. You'll have a like new carb for about 250 bucks.
 
The holley kit does come with the throttle bushings, but i don't think you'll need them, it most likely is flooding abit & it will seep out the shafts, you can get the kit from O'Reilly's, maybe even AutoZone, this will save you shipping, there like 38-40 bucks, it will have everything you'll need for a "complete" rebuild, just make sure you clean the parts thoroughly.
 
JoeDust451 said:
The holley kit does come with the throttle bushings, but i don't think you'll need them, it most likely is flooding abit & it will seep out the shafts, you can get the kit from O'Reilly's, maybe even AutoZone, this will save you shipping, there like 38-40 bucks, it will have everything you'll need for a "complete" rebuild, just make sure you clean the parts thoroughly.
Click to expand...

What kit is that? Do you have a link or part number? In almost 30 years of rebuilding these things, I have not seen a kit that comes with bushings as of yet. I am aware that bushings can be had seperately from the aftermarket but Holley does not consider this a service item.
 
ramcharger said:
What kit is that? Do you have a link or part number? In almost 30 years of rebuilding these things, I have not seen a kit that comes with bushings as of yet. I am aware that bushings can be had seperately from the aftermarket but Holley does not consider this a service item.
Click to expand...

There not bushings really (i should have said strap seals), thats only if the base is worn, then you need to drill & install bushings, what i'm talking about are the factory "nylon" strap seals that wrap around the inner recessed parts of the shaft by the throttle bores & outer area.
 
JoeDust451 said:
There not bushings really (i should have said strap seals), thats only if the base is worn, then you need to drill & install bushings, what i'm talking about are the factory "nylon" strap seals that wrap around the inner recessed parts of the shaft by the throttle bores & outer area.
Click to expand...

Aha! :) Yep, now I know what you speak of.
 
here is another symptom. after i shut the car off, and i look down the carb, i see that the carb is still pumping fuel out of the two little holes. so i have to floor it just to start it cause it floods out
 
You mean the circle within the circle? That would be the boosters.

Electric or mechanical fuel pump?
 
Dude it is flooding, due to floats not set right or the needle and seats messed up.
You need to rebuild it.
 
SGBARRACUDA said:
Dude it is flooding, due to floats not set right or the needle and seats messed up.
You need to rebuild it.
Click to expand...

Yeah, it's flooding for sure. Let's find out why..... He may also be using an un-regulated electric pump without a regulator, hence why I asked my questions.
 
no electric pump. i just got the stock manual for now. i got a holley blue, but need to get a regulator, and a fuel pressure guage for it first
 
It is floading & your rings aren't happy, its most likely the needle/seats.
 
Like SG and JoeDust say, it's time to rebuild and replace the needles and seats. Floats could sunk/sticky too. When you rebuild, check for any rust in the carb too or it's just pissing in the wind if you have rust in your tank.

The only other thing to do is to adjust the float levels and that can be done externally on a Holley.
 
I just picked up the complete rebuild kit for it. It was 47.00 out the door, but after looking inside the package, there is no way

will any of you guys on here that do know how will rebuild it for me??????lol
 
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