Carb questions - leaking!

[JHART]

Ok ..so i found that my carb is leaking from what looks to be under the primary bowl ... My question is, is it worth pulling the carb just to fix this leak that looks to be just a gasket OR should i pull it and rebuild it while i have it out?

Also ...any of you other Holley users ever seen this and hopefully you have and have some tips!

I took some pics best i could of the leak. Yes i know she's dirty but remember i just bought her this week as is. Sorry if the pics arent the greatest but its kinda a hard spot to get a good pic of. Some of the pics are sideways ...sorry.

Thanks in advance!

-Hart

[rage'nrat638]

well it looks like your have a edelbrock intake yes?
looks like a holley carb yes?
i have no ideal why you have that kind of adaptor plate in there.
both the intake and carb are squrebore
there should be no adaptor plate used. just a gasket.

unless you have a universal mount intake. in which case this plate is what would be used.

i also included a universal intake manifold picture


also the gas leak is likely the front pump. or the front bowl gasket. both are very easy to change on or off the truck.

[JHART]

Thx for the reply! .. So your saying i should take off the carb to see what that plate is all about? If its square should i leave it?

How would i change that gasket while the carb is still installed? Those screws look a bit hard to get at with a screw driver.

I also have another question ( i know i am full of questions sorry ). The carb i have has what i am told to be a vacume choke? Can someone explain this to me and please tell me if its any good. The carbs i read about most of the time are either Mechanical Choke or Electrical. Which one is best?

[Cobraguy]

Can you remove the air cleaner to us a better look? I believe you have a vacuum secondary not choke.

[corn]

Looks to me like your pump diaphram is leaking. Pop the carb off & flip it over. four little screws & put the new one on. I got one at o'rielly's for less than $10 to do the same fix...

[JHART]

I will take some more pics tomorrow when i pull the carb off. Thanks for the help guys.

vacuum secondary? Is this good or bad. I want to have a carb that will perform well on the street as a daily driver. This one tends to choke when i get on it.

[cableguy0]

your choking when you get into it might be caused by that leaking accelerator pump diaphram. just unbolt the front bowl no need to remove carb. that plate under the carb looks like just a sqaure spacer. nothing wrong with it wont hurt anything and as a matter of fact its probably helping your power just a tad. the vac secondaries is what you wont on a heavy street truck.it sounds like your carb might just need a little tuning but first take care of your leaks

[JHART]

Thx .. i will try that first then. I agree .. i need to fix that leak .... gas leaks scare the you know what outa me. Last thing i need is my baby to catch fire! Also is there any tuning guides for Holley Carbs? I'm far from an expert when it comes to that.

Also which Choke is better mech or elect?

Thx again!

[rage'nrat638]

yup thats all i am getting at we just need to make sure the spacer is just a spacer and not some uneeded or incorrect spacer plate. i am going to do a FAQ on 600 HOLLEY rebuilds but just have not done it yet.
any questions feel free to p.m. me and ask away, your pal mark
i like electric choke my self but have had both. a choke is better than no choke

[JHART]

Awesome ... so then my electric choke is good i take it. I think i am going to rebuild the carb anyway just for piece of mind. I have rebuilt a few Quadrajets before but never a Holley ...anything i need to know about?

[hvychve]

I'm going to agree with above listed, however , being that the accelerator pumps are common for leaking, I found that on many cases of rebuilding customers carbs and my own hollys ; is that the accelerator pump cover itself gets warped , usually due to either over time of pressing throttle and or too tight adjustment , you want a small gap between accelerator are and adjustment screw, I usually take the front bowl off, install with the blue gaskets( these are usually the ones you can take off again without scraping the gasket) but before It goes back to gether I stick the accelerator pump housing in the vise, (open end up) and file until all level, you will notice if you hold housing up at angle , that it is probably bably distorted, file it if you are replacing diaphragm, or you can replace with a bigger cc style and than it will be new , so no need to file, which ever the case, Holleys are common for leaking at this area, and yes I agree , fuel leaks under the hood are bad. good luck.
Andy

[cableguy0]

holleys are pretty straight forward on the rebuild. the directions that come with the rebuild kits will get you through it no problem if you are reasonably mechanically inclined. i personally prefer electric choke much easier to deal with hit the gas and turn the key.

[JHART]

Ok update time ...

I changed the accelerator pump diaphram and it fixed the leak so thank you for the input. You saved me some $$$ ... if your ever near Lemoore California let me know and the beer is on me!

BUT ( and you all know this was coming, the infinate BUT), she still seems to be running a little rough. I cant tell if its timing, carb, or ****ty exhaust. You guys have any other ideas i can do to remedy this or at least figure out what the actual problem is?

She idles real low , so i adjusted the idle. When i put it in gear the idle goes down real low and i have to give it a bit more gas to get the truck moving. I'm not sure how else to put it ..she's just not running right ...runs rough.

[JHART]

bump

[brak]

sounds to me like you need to adjust the idle mixture.

below are two links from holley's site, they should help you get the carb adjusted correctly. I wasn't sure which model you have, so i posted the info for a 600cfm electric choke.

Owners manual

Quickstart Guide

[JHART]

So the idle mixture will cause my truck to idle that low when its in gear? It almost stals out. Its real low. Specially when i am at a stop light and its in gear. Put in nuetral and it idles normal.

[brak]

Originally Posted by JHART

So the idle mixture will cause my truck to idle that low when its in gear? It almost stals out. Its real low. Specially when i am at a stop light and its in gear. Put in nuetral and it idles normal.

could also be vacuum related, but in the absence of any obvious vacuum leaks, i would check the mixture.