Carburetors: A Cautionary Tale

The "O" rings on the tube will leak also. Might get some of those..

 

Already took care of that trust me. Before I put it back together I put thread sealer between the tube and the joint it goes into, in addition to the o ring.

 

Not sure we are talking the same tube.. I'm referring to the tube that feeds the secondary bowl next to the linkages. There are two "O" rings.

 

Yep that's what I meant. Put thread sealer on both ends as well as the o rings. Not gonna leak from there anytime soon lol..

 

Good.. I do fear a fuel leak myself.. One of them areas to keep BOTH eyes on lol

 

Yeah I used the same thread sealer on the fuel pump. It works well. I realize there's a lot of different opinions on it, but nobody is gonna convince me not to replace the gaskets after what happened lol. May be a little overkill for some but that way I don't have to worry about it.

 

That may be true of a newbie but I've raced dirt late models and modifieds for over 30 years. I also did custom carb work for other people when I raced. The paper gasket works as designed, just detail the screw and nut for a flat surface, adjust properly, and you will have no problems. I will wager I've spent more time adjusting floats and fine tuning Holley carbs than most on this site. I stand by my statement.

You should never, NEVER, use any type of sealer around a carb. There is a reason the inlet threads are either o-ring with a gasket or inverted flare. I've seen more sealer inside a carb plugging passages and sticking floats thru the years than I can count. It's simply not needed or recommended by any carb builder.

If it's clean and assembled properly, the o-rings on the transfer tube is a fine seal. They've been used since the late 50's without problem. If it leaks you pinched it putting the tube in or it's old and brittle. Absolutely no sealant is needed other than a dab of petroleum jelly as lube when putting it together.

Changing a gasket every time is not a problem if you want the hassle, that's fine but not needed. Realize there is a gasket on top and bottom of the nut and they are different bore sizes. No need for doing it, but no damage caused either. The sealants around a carb is a different story. You are creating a problem going that route.

SPark

 

Yeah, I never use sealant on carbs.

 

Man that sucks!!! Those paper gaskets also differ from a holley part to aftermarket. The Holley ones are pretty tough. Aftermarket kits use a different style of paper. It will crush and split if you tighten it a bit too much. Too late for advice now obviously but never anything but a Holley factory kit for this guy. Glad to hear you saved the car!!!

 

I have never ever had a needle and seat gasket leak, ON ITS OWN. I have been working and rebuilding Holleys since 1979. If you adjust the needle and seat, then you should always be alert for the tell-tale wetting on top of the bowl, or more typical, the jet spray that normally occurs when the gasket separates or tears. At that point you just swap to a new pair and go on. most of the time, you dont even have to bother the float adjustment.

the gaskets are quite frail, once they have been installed for a while.

I saw a few references to sealants. NO!!! just keep the surfaces clean and use fresh pair of needle and seat gaskets. sealant is not needed nor designed to seal that leak path. the little black gaskets do fine.

fresh gaskets enable a wide amount of adjustment and tuning without much fuss, but after they sort of bond to the bowl or screw or nut over a period of time, adjusting the needle and seat without gasket issues is about 50/50 chance of needing fresh gaskets. Working with holleys for years gives you ammo on what to keep stock piled. needle and seat gaskets are a must have (period).

the new kits are running a nylon style gasket quite nice. you can also by multiple pairs (paper or nylon) on ebay for pretty cheap. However, I am not sure if they relax over time and maybe start to leak. I have used nylon bowl screws and powervalve gaskets for sometime without issues, though.

 

I didn't use any sealant on the float adjustment screws, just on the end of the fuel transfer tube, because the o rings that go on it don't make a perfect seal. A little added protection... I also replaced the paper gaskets with copper crush washers. Problem solved, no leaks, and I don't have to worry about them tearing. Thank you to whoever suggested that...

 

Almost all the failures I see are a result of over torquing because many think its "extra insurance". It's very easy to make the paper gaskets into non-stick versions if you use chapstick or vaseline prior to installation(if you pre-lube them a bit earlier than needed.. they will "soak up" the oils better and last longer during multiple removals/adjustments too).

Otherwise.. the nylon or teflon coated deals are well worth the money. Since I'm all about overkill and still see those stick on occasion as well(usually only on long term installs that have been over-torqued.. I still use chapstick with the teflon versions too and there's always at least two tubes in my carb toolbox. Chapstick saves money and reduces headaches when you least need or can deal with them.

Glad you saved your car after all was said and done.

 

HaHa, I thought I was the only one who still put chapstick on my carb gaskets! I do use the nylon ones on the needle and seat adjusters though with no chapstick.

 

It's an old-timers trick I picked up through the years. Also works on o-rings too and doesn't get squished and washed out as easily as vaseline does.