[OVERULD]

Decided to take the 71 455 HO for a drive yesterday afternoon. After I backed it out of the garage, I left it running in the driveway while I went back into the garage to see if I saw any new puddles...cause, you know - it's a Pontiac. Anyway, after wiping the few puddles off the floor, I went back out to the car which was in high idle and sounding great. I noticed a big puddle under the front of the car and could see steady drips landing in it. As I got closer I could smell gas. I opened the hood and could see that it was coming from the vicinity of the fuel pump, so I pulled the car into the street, away from the house and off my driveway. When I got back out to take a closer look, with the engine still running, the leak had diminished to a much slower drip and as I watched, it just stopped.

The car never stumbled or missed as it was at high idle with the stove choke, and when I reached under the breather to bump the throttle down to normal idle, it continued to purr like an HO should. So, I drove the car about 50 miles over the next hour and never had a stumble or miss or leak. It sat in the garage overnight without a single drip.

Anyone every had this happen? Any ideas on what the source of the leak may have been? And, who is the best source for a correct replacement fuel pump and replacement rubber lines?

Thanks,
BJ

[wbnapier]

Yes. Two times.

I once added an octane booster to an almost empty tank before heading to the gas station. The gas swelled and the hoses leaked at every junction. By adding pump gas and lessening the proportion of octane booster:gas, the leaks went away. Bizarre. The hoses were new, the bands/clips new, and everything fine. I never add octane booster to anything but a 1/2+ filled tank now.

Not your situation, I know.

Second time, on my GTO, from the fuel pump to the carb is supposed to be ⅜" and from the fuel pump back to the tank is 5/16". There are two nipples on the pump, one going to ⅜" and a second going rearward to 5/16". Mine were mixed up and caused intermittent leaks. Make sure the nipples are the right size, the hoses the right size, and the clips are meant to work with those sizes.

[SD455DJ]

BJ, Make sure to check your oil in case the fuel pump is leaking into the crankcase.

Dennis

[OVERULD]

Thanks Dennis, great tip! Hadn't even thought of that. I checked it this morning and it looks fine. I am going to replace the pump and rubber hoses out of an abundance of caution. Can you recommend a good source for the correct pump?

BJ

[ta-kid]

When people install the fuel pumps two common issues can happen.Over tighten fitting at pump, which is on the steel feed line to the carb ,splitting the flare or in their attempt to make sure its tight they slightly twist the fitting block that is soldered to the bottom of the pump where the steel line connects,cracking the block solder joint.A fine crack will leak fuel under pressure.Should always support the fitting block with a proper size wrench before tightening fitting.

[SD455DJ]

Originally Posted by OVERULD

Thanks Dennis, great tip! Hadn't even thought of that. I checked it this morning and it looks fine. I am going to replace the pump and rubber hoses out of an abundance of caution. Can you recommend a good source for the correct pump?

BJ

BJ, Dan got them at his local CARQUEST Auto Parts store. They were the only deep cannister Pontiac pumps are correct for the '71 455HO's. I can't recall the part #...

Dennis

[gloryrestoparts]

Originally Posted by SD455DJ

BJ, Dan got them at his local CARQUEST Auto Parts store. They were the only deep cannister Pontiac pumps are correct for the '71 455HO's. I can't recall the part #...

Dennis

I'm betting thats the airtex 41632(? not 100% on that nbr). carter is M6122, iirc

[OVERULD]

Thanks guys. I’ve been too busy this week to research it, but hope to get one sourced soon...deer season is here and my wife is starting a new round of chemo on Thursday, so not much time for the cars right now.

BJ

[77 Canamman]

Advance (CARQUEST) part number 3541159 for $39.99.

[OVERULD]

Thanks!

[pggto]

BJ, I bought an AC Delco one from summit for my 71 HO car. I was pretty happy with the part.

https://www.summitracing.com/parts/ado-41382

[OVERULD]

Thanks Paul!

BJ