Holley Fuel Inlet Wrench

[Daniel S.]

Looking to change the fuel filters on my Holley tripower carb setup. Have been trying to find the proper wrench to do so. Last time I used a conventional open end wrench. While it worked, it was rather difficult to do so without damaging the inlet nuts and/or carb body. I have been searching for a GM Thexton 361 1" fuel inlet wrench but cannot seem to find one. Does anyone have a source where I could procure one? If not, is there another tool that is available to assist with doing this job the right way. Thanks for your help..Dan

[Stuart F.]

Re: Holley Fuel Inlet Wrench

Sets of regular "Flare Nut" wrenches are available at most any Auto parts store. I find they work well for me, but I'm not sure if you have a special application on your carbs. Flare Nut wrenches are like an 8 sided box wrench, but with a notch to slip it over the tube onto the fitting. They won't work in every circumstance, i.e. never found anything yet to work on old brake line fittings w/o rounding them off. They somehow seem to be too soft and you almost always have to use a vice grip on them and hope you can save it if you need to.

Stu Fox

[Stuart F.]

Re: Holley Fuel Inlet Wrench

Daniel;

Did you ever get the wrench that you needed?

Stun Fox

[Wayne M.]

Re: Holley Fuel Inlet Wrench

Sets of regular "Flare Nut" wrenches are available at most any Auto parts store. I find they work well for me, but I'm not sure if you have a special application on your carbs. Flare Nut wrenches are like an 8 sided box wrench, but with a notch to slip it over the tube onto the fitting. They won't work in every circumstance, i.e. never found anything yet to work on old brake line fittings w/o rounding them off. They somehow seem to be too soft and you almost always have to use a vice grip on them and hope you can save it if you need to.

Stu Fox

Stu --- the problem I've found is that your typical flare nut wrench binds on the lower fuel bowl screw/boss. A regular adjustable wrench does the trick for me. Maybe that Thexon wrench that Daniel refers to is the solution.

[Stuart F.]

Re: Holley Fuel Inlet Wrench

Wayne;

Thanks. That's good to know. Nothing is as easy as it may seem when working on Vettes. I've come up with some of my best solutions (tricks) through the school of hard knocks.

Stu Fox

[Daniel S.]

Re: Holley Fuel Inlet Wrench

I have not been able to locate a Thexton or similar wrench. I will try a flare nut wrench this time. Had to order one online believe it or not. None of the local auto parts stores or Sears carried them in 1". What makes this job tough is not with the fuel line nuts themselves, but the fuel filter inlet nut. Its thin and hard to get at without risk of rounding the nut off. The middle and back carbs are most difficult due to proximity of the carbs in front of them. The front carb is the easiest of the three.

[Clem Z.]

Re: Holley Fuel Inlet Wrench

I have not been able to locate a Thexton or similar wrench. I will try a flare nut wrench this time. Had to order one online believe it or not. None of the local auto parts stores or Sears carried them in 1". What makes this job tough is not with the fuel line nuts themselves, but the fuel filter inlet nut. Its thin and hard to get at without risk of rounding the nut off. The middle and back carbs are most difficult due to proximity of the carbs in front of them. The front carb is the easiest of the three.

a good quality 1" open end is what works, never use a adjustable wrench unless you want a rounded off carb fitting. use a fitting wrench on the flare nut. always put teflon tape or teflon paste in the flare nut to lessen the friction when tightenig back up. this is not for sealing just to reduce the friction so you can get the flare leak tight.

[Stuart F.]

Re: Holley Fuel Inlet Wrench

Clem;

Thanks for that explanation for using thread tape. I have long held an aversion to doing that for fear of some getting through the fuel line and hanging up a needle/seat. A friend who was using a set of dual quads that I set up for him had a big belching fire coming out of his exhaust dump pipes at the drag strip one night and he wanted to blame me for it. Turned out it was his fuel line connection to the carbs that was the problem with over zealous use of thread tape. I saved the night for him with the old "screw driver rap" trick to dislodge it until we could pull it apart to clean it (post fire).

So I guess using it is fine and does have a purpose, just be careful.

Stu Fox

[Clem Z.]

Re: Holley Fuel Inlet Wrench

Clem;

Thanks for that explanation for using thread tape. I have long held an aversion to doing that for fear of some getting through the fuel line and hanging up a needle/seat. A friend who was using a set of dual quads that I set up for him had a big belching fire coming out of his exhaust dump pipes at the drag strip one night and he wanted to blame me for it. Turned out it was his fuel line connection to the carbs that was the problem with over zealous use of thread tape. I saved the night for him with the old "screw driver rap" trick to dislodge it until we could pull it apart to clean it (post fire).

So I guess using it is fine and does have a purpose, just be careful.

Stu Fox

the way to clear a piece of debris in the needle/seat is to remove the fuel line from the carb,block the end of the fuel line,start the engine and run the carb dry. this will drop the float and the needle/seat will be in the wide open position and when you connect the fuel line back up the incoming gasoline SHOULD flush the debris from the needle/seat.

[Jim T.]

Re: Holley Fuel Inlet Wrench

On my latest Holley installation the installment and adjustment instructions have a picture of installing a dual fuel line using teflon tape. Picture instructions say "Do not put teflon tape over the first two threads."
The instructions also mention to use a quality inline fuel filter between the pump and carburetor. Absence of such a fuel filter voids the carburetor warranty. Holley has fuel filters (chrome) for hard line connections 5/16 #162-532, 3/8 #162-530, and 1/2 #162-531.

[Stuart F.]

Re: Holley Fuel Inlet Wrench

You see! Holley finally figured out there could be a problem. I wonder how many fires it took? The Carter WCFB's in question did not have an inlet filter or screen at the Carburetor(s), back in the day. In fact my early AFB's never had a screen either until later. They, of course, would help prevent any contamination from Thread Tape at the connection. as for the method of clearing a contaminated needle/seat, sounds good. I concur. In the heat of the fire though, the last thing you want to do is disconnect the fuel line at the carb, I would think. It's a good solution after the situation cools down.

Stu Fox

[Wayne M.]

Re: Holley Fuel Inlet Wrench

a good quality 1" open end is what works, never use a adjustable wrench unless you want a rounded off carb fitting. use a fitting wrench on the flare nut. always put teflon tape or teflon paste in the flare nut to lessen the friction when tightenig back up. this is not for sealing just to reduce the friction so you can get the flare leak tight.

Speaking of fittings, Daniel's pic seems (IMO) to show the carb-to-bowl fitting similar to the one on the bottom of my attached pic. The top ones with the wide flats were on my original '69 400hp set-up, and the associated tubing is 0.375" od. The tubing on the bottom is a smaller 0.315". Wonder which one is period-correct ?

[Clem Z.]

Re: Holley Fuel Inlet Wrench

Speaking of fittings, Daniel's pic seems (IMO) to show the carb-to-bowl fitting similar to the one on the bottom of my attached pic. The top ones with the wide flats were on my original '69 400hp set-up, and the associated tubing is 0.375" od. The tubing on the bottom is a smaller 0.315". Wonder which one is period-correct ?

the top picture are the original fittings used on the 3 X 2 setup. the bottom picture shows the holley supplied ones that comes with some of their over the counter carbs