73 Monaco wagon

The Holley 2 bbs. develop warped air horns because the air cleaner hold down rod doesn't fasten into the base, but rather just fastens into the air horn. So when folks tighten the air cleaners down and go through heat cycles the air horns slowly but surely warp, and then the vacuum is lost that pulls the fuel out of the metering nozzles. But Autoline rebuildiers that Rock Auto uses know about this and they have a technique to press the air horns flat again and surface them so the problem is fixed. I haven't had any problems with the Autoline rebuilds from Rock Auto and suggest you invest in one of them. Your problem is typical of that problem along with substantial stumbles and surging on light accels, if it even keeps running. When you put one on though, do not tighten the air cleaner down any more than absolutely necessary to prevent a recurrence.
I had one like this when I younger, dumber and broker...
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The air horn was cracked and deformed enough that looking down the carb while working the accelerator the fuel just trickled down the sides and never sprayed at all. Being a broke guy with a rebuild kit and very little budget, I patched it back together with epoxy. It passed emissions and ran pretty good for another year before it had to be replaced. I honestly can not recall which carb it was... dumb design, not passing the stud through to the body.
Can you tell me what a power valve is? I'll google it for Holley carbs. Thanks
At wide throttle openings the additional fuel is delivered by either metering rods or a power valve. Look here for basic circuits explained... CARBURETOR CIRCUITS
 
Some of the photos are from prior to me soaking it and rebuilding it. Can you tell me what a power valve is? I'll google it for Holley carbs. Thanks
The power valve enriches the fuel mixture when the engine is under load or under hard acceleration ... if it's stuck open or broken and leaking at ldle, it's dumping fuel into the mix and could stall out your engine. You could seat your mixture screws and see if the car still runs if you want to check it ... but honestly, as most are saying, I'd just shelf or dump the carb and get a new one. You'll be purring along before you know it.
 
If you wagon has a canister under hood, it should have a carburetor with a bowl vent on it as well (front, pass side). Bowl vents help provide better hot starts.

The Autoline carburetor uses the same air horn that is from whatever core that they used to rebuild. They just press the airhorn flat and maybe surface it a little as well. So the problem could recur if you tighten the air cleaner too much - only tighten it as little as you can get away with.
Ok got it. Thanks. Now am left wondering if this is the original carb, if the canister hose "goes to nowhere".
 
I had one like this when I younger, dumber and broker...
View attachment 129505
The air horn was cracked and deformed enough that looking down the carb while working the accelerator the fuel just trickled down the sides and never sprayed at all. Being a broke guy with a rebuild kit and very little budget, I patched it back together with epoxy. It passed emissions and ran pretty good for another year before it had to be replaced. I honestly can not recall which carb it was... dumb design, not passing the stud through to the body.

At wide throttle openings the additional fuel is delivered by either metering rods or a power valve. Look here for basic circuits explained... CARBURETOR CIRCUITS
Beautiful Newport. I had a 70. Thanks for the info. Will read up.
 
Ordered the Autoline Rochester 2bbl from RA, as recommended by the collective wisdom of C-body tribal elders. We shall see what magic it can work. I am running out of time to have hope of getting this monster on the road to hit any summer cruise nights this season, and I need a 'great leap forward'. Wrench time available vs. money. Maybe I will keep the Holley and get a new power valve, needle valve, and replace the original black float with a brass float, as a 'just in case' for the future.

Hope that 400 sings like a canary when I bolt on the new Rochester.

Still have smoke leaks from LH valve cover after replacing with heavy duty gasket and using sealant on BOTH sides of gasket (yeah, I know, 'nuclear option') and sealing up crack in metal above bolt head with job weld. Crack sealed, but gasket at lower center of valve cover still appears to leak.

Have not yet replaced gasket on passenger side. It leaks and smokes a bit too.
 
Ordered the Autoline Rochester 2bbl from RA, as recommended by the collective wisdom of C-body tribal elders. We shall see what magic it can work. I am running out of time to have hope of getting this monster on the road to hit any summer cruise nights this season, and I need a 'great leap forward'. Wrench time available vs. money. Maybe I will keep the Holley and get a new power valve, needle valve, and replace the original black float with a brass float, as a 'just in case' for the future.

Hope that 400 sings like a canary when I bolt on the new Rochester.

Still have smoke leaks from LH valve cover after replacing with heavy duty gasket and using sealant on BOTH sides of gasket (yeah, I know, 'nuclear option') and sealing up crack in metal above bolt head with job weld. Crack sealed, but gasket at lower center of valve cover still appears to leak.

Have not yet replaced gasket on passenger side. It leaks and smokes a bit too.
Meh, you get em right at some point. Most important thing is to get her running happily, then chase down all that other crap... glad you got a new carb. It's never been anything but the right decision for me timewise. Frankly, depending on the carb, I love rebuilding them so time spent is usually worth it. Certain carbs, however never pan out. And from the reviews on this board and experience, throw the original on a shelf and get driving!
 
Meh, you get em right at some point. Most important thing is to get her running happily, then chase down all that other crap... glad you got a new carb. It's never been anything but the right decision for me timewise. Frankly, depending on the carb, I love rebuilding them so time spent is usually worth it. Certain carbs, however never pan out. And from the reviews on this board and experience, throw the original on a shelf and get driving!
Yeah this is kind of like an interactive you tube. I saw other posters on other sites describe the Holley as an easy to set up carb but basically throw away when it was worn out. Forward!
 
It arrived. Was surprised to see it actually is a Holley. The ad on Rock Auto listed a Rochester as what they would give as a replacement, for a 73 Monaco. Still not sure I want to give back my old Holley for the core. But I would like to apply that $65 core fee elsewhere. Not like I have a numbers matching 'Cuda.

It looks good. Clean. New-ish.

Going to replace my fuel filter...

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Looks like the same one I got. I think it will make a great difference. you don't have to tighten the carb bolts and nuts too hard. You don't want to warp the base.

Dave
 
Especially do not tighten the wingnut on top the air cleaner any more than necessary to keep it in place. If the air cleaner is on the verge of rattling, you have it about right.

I do not understand why you have been thinking you would be getting a Rochester brand? I could never find that brand in Rock Auto's list, nor do I recall Chrysler using that brand very often, if ever on a 360?
 
Especially do not tighten the wingnut on top the air cleaner any more than necessary to keep it in place. If the air cleaner is on the verge of rattling, you have it about right.

I do not understand why you have been thinking you would be getting a Rochester brand? I could never find that brand in Rock Auto's list, nor do I recall Chrysler using that brand very often, if ever on a 360?
The listing said Rochester on Rock Auto's site, when I looked. I'll see if I can make a screen snip and post it. I knew my carb was a Holley, but didn't know enough about what a Rochester looked like to know any better, when looking at the carb on their site. It looks similar but a bit different than mine. The large metal tube in the front on theirs is not present on mine. Presumably that is for the carbon canister. Also, their replacement carb has an exposed lever running left to right over top the carb, covering the word "Holley". Mine does not. I assume there were just minor variations of the same general design over the years, changes made for ease of manufacturing, cost savings, emissions improvement, etc. Frankly the carb I am taking off looks slightly cheaper.
 
Especially do not tighten the wingnut on top the air cleaner any more than necessary to keep it in place. If the air cleaner is on the verge of rattling, you have it about right.

I do not understand why you have been thinking you would be getting a Rochester brand? I could never find that brand in Rock Auto's list, nor do I recall Chrysler using that brand very often, if ever on a 360?
Yes... I know enough about carbs to know Rochester was a GM part, and who among the Big Three would want to buy 'the other guy's' parts? But I am sure it happened. If there was a business case, Engineering, Accounting, Marketing, Sales planets all aligned... I believe GM supplied power steering and or tilt/telescoping steering wheels to different makers. AMC had no shame in using FoMoCo parts, on the CJ, etc. I bet to be a carb supplier was to get beat up for cost constantly....commoditization.

But yes sir it is a Holley they sent. Why their listing says Rochester I do not know. Web designer ignorance meets customer ignorance. Nonetheless I got what I needed!

I'll keep it almost loose! Thanks for the tip.
 
Looks like the same one I got. I think it will make a great difference. you don't have to tighten the carb bolts and nuts too hard. You don't want to warp the base.

Dave
Thanks Dave. I need to find out torque spec and use my torque wrench.
 
So over time since I cleaned out the fuel line over the past month, the car went from running, to running but then slowly dying from idle (carruhhhnnn, carruhhhnnn, carruh- dead) to not running at all except from pouring gas down the carb. I will pull the fuel line off at the carb and see if any gas comes out. I am replacing the fuel filter anyway. When I do that I'll see if it is plugged. Work my way backwards toward the tank. The fuel pump is original and since it sat in a junkyard presumably for decades and I already bought a replacement I may as well put that on and keep the old one as a spare.
 
Got the Autoline rebuild and installed it. Waiting for time to replace fuel pump and filter. Took old carb out and it was full of fuel and spraying ok, but when I unhooked the fuel line from carb it was dry as a bone. I'm baffled.Must be a blockage somewhere in the line.

Autoline Holley did not include the lever shown so I had to scavenge it from my old one.

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Got the Autoline rebuild and installed it. Waiting for time to replace fuel pump and filter. Took old carb out and it was full of fuel and spraying ok, but when I unhooked the fuel line from carb it was dry as a bone. I'm baffled.Must be a blockage somewhere in the line.

Autoline Holley did not include the lever shown so I had to scavenge it from my old one.

That link is an optional one and used only on cars equipped with speed control.
 
Re-man Autoline carb installed. New Delphi fuel pump installed. New clear fuel filter installed. Car starts and runs. Acceleration seems a bit flatter than with previous carb, maybe a timing/tuning issue? But bigger issues are this:
1) After 24 hours since running, the fuel filter gets empty of fuel. Apparently it drains back to the tank? Does it need some kind of one way check valve to prevent that?
2) Once I get it running, it has same problem as before, I have to really give it a lot of gas (push on accelerator pedal and raise up rpm) in order for the car to go up hill. Tranny slipping, or...? Solution?
 
Its hard to tell what is going on without actually being there in person. I guess you have to go over everything from the start til you find the problem. Sorry I couldn't be of more help.

Dave
 
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