Update on the 72 Coupe (Video Q&A)

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Joined
Aug 7, 2024
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106
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Location
Orlando, Florida
My Car
1972 Coupe
(Sorry if this is duplicated. From my end, it does not appear my earlier post in the Build Thread uploaded, so I am covering bases.)

Alright gang...finally had my first window of opportunity to start diving into the 72. Needless to say, there is a shit-ton of work ahead in terms of body work, rust repair, etc. However my first focus is to get the engine situated and running properly. When she showed up from Cali, she was running rough...think I mentioned the issue about her seemingly struggling for gas and stalling after you get her up to a certain speed when I drove her out there. Now that she's here, the issue is definitely more elaborate.

She will idle fine when in Park or Neutral...revs good...sounds fairly decent without having done anything major yet. However, when you drop her into Reverse or Drive, the idle drops significantly and she basically chokes...or stalls completely. So I made this video before I get into anything this weekend to see if you guys see something glaring that I am not. Again, please pardon stupid questions...I know how to do some engine work, but admittedly there is a lot I don't know. I have segmented this into three sections of questions and sorry, had to put it on You Tube because of size. Give it a watch and comment back here.



1) the EFI / fuel pump mess this guy left me with.
2) the random unplugged hoses to nowhere.
3) recommendations on changing out the air cleaner and breathers.

I welcome your thoughts.
 
Update: Much thanks to Bob for dropping me an email about this. Not sure why I didn't realize (most likely because there is nothing in my center console) that the unknown lines on the passenger side firewall are for heat and (ironically) an AC unit that at one time was on the platform that the troublesome EFI is so eloquently zip tied to. So that answers that question.

I'm going to take out the EFI and put in a new hard fuel line, along with the new manual fuel pump to run it the way it was originally run and see if that perhaps solves the running issue...or at least improves it. More to come.

PBR
 
Question is it really an efi setup or just an electric fuel pump? Zip tyes on fuel lines and gear clamps. Need to clean that up for sure!
Sorry, should have clarified. It is simply a Edelbrock electric fuel pump (from what I've discovered, a $70 quick add). Not a full EFI setup.

I think he was having either fuel filter, or fuel line issues (maybe vacuum) which weren't addressed and when he talked to his mechanic about being tired of having to pump the car rigorously to get it started..."said mechanic" cut the line from the manual pump, stuck this in there and said problem solved. It may have worked for awhile (not sure) but I can tell you in the last 24 hours of doing diagnostic, I cannot get this thing to not stall once its in reverse, or drive. Idles fine...then you go to switch it into gear and she chokes out. I can't even back it out of the garage a few feet. Now, I would assume there are potentially other issues that could be the root (vacuum leak, filter, etc.) but I'm trying to start with getting it back to normal operating condition and troubleshoot it all one step at a time.
 
Even an old classic carburetor car will start with 2-3 attempts. One depress to set the choke and couple of cycles of the ignition to get the fuel into the carb even using the original fuel pump. My guess carb needs rebuild, plugs?, wires, inspect cap and rotor. Just a plain tune up. I would baseline what you have before modifying anything. Just my opinion. I would also get some shop manuals. Use the search on this site to find lots info also.
TonyD
 
LOL.... "$hit-show" - one of my favorite automotive terms.....

Red Edelbrock pump is just an electric "clicky-clack" pump for carbs and it's zip tied to your lower AC compressor mounting bracket. They work, but not usually long term. Handy for quick fixes or roadside emergencies. The AC hoses would have connected to the compressor.

Corrugated brown foil hose off the blue canister is the vapor hose, it connects to the side of the air filter. Canister will also have a rubber hose that connects to the steel vapor line running across the firewall. That runs down the trans tunnel to the vapor separator on top of the fuel tank.

Leaking gasket is the accelerator pump diaphragm. Very common leak on the Autolite/Motorcraft 2 barrel carbs. Always keep a spare around. I'd recommend you just rebuild the carb. You need to know the part # on the carb to get the correct kit, it's stamped into the side of the driver's side front mounting lug. Super simple to rebuild, and it may help with your stalling problem.

You can remove the elbow from the side of the factory air cleaner, pop a hole in the bottom of the chrome unit, and clip it in place. Connect a hose to the elbow on the passenger valve cover - easy peasy.
 
Thanks for the tips above guys. Appreciate that. I'll check the vaccum hoses and most likely will rebuild the carb. Sounds pretty straight forward.

Here's the end of todays progress, which did not end as I had hoped.

Started with an engine clean up, then changed the plugs, wires, oil filter, and oil, as well as replaced the air cleaner (figured out all the breather stuff).. but as suspected, none of which made any significant difference in the way she was running, but needed to be done regardless. Then I figured I'd tackle the leaking gasket on the carb, which turns out, is a gasket no auto parts store has, so I am going to get the rebuild kit and deal with that. They actually did sell the kit. So I'll grab that tomorrow.

So then I figured I'd tackle the electric fuel pump issue, to see if perhaps returning the system to the manual pump would perhaps at least negate some of the issue. So...I took out the Edelbrock....ran the fuel line back into the manual pump...then fitted the line running from the fuel pump up into the clear fuel filter and into the carb with new hoses and a new clear fuel filter. I didn't put in the new fuel pump I bought, as when going down to reinstall the fuel line, the existing pump looked fairly new. Hindsight says I probably should have...as alas...after I did all that, and turned the car on, she cranked, started up, ran for about 30 seconds...then died. Now she won't start, she cranks fine, but she's obviously not getting gas. Zero. Nada.

So...tomorrow am I am going to try to trouble shoot again, this time by replacing the existing old fuel pump with the new one I bought...and giving her another go. Perhaps because it was bypassed, the old one maybe sat idle too long and just needs to be replaced.

If that doesn't work...then I need to re-evaluate the situation which could only mean that I have a blocked or bad fuel line somewhere...although she was getting gas and the old clear filter was full when I removed it. So I would be shocked. It seems to me that its the pump.

I'll keep you posted tomorrow. Thanks again for the advice on the hoses and carb guys. Appreciate it.

PBR
 
Satruday morning update guys. Easier for me to just video stuff and show you what I am talking about. Attached is the update, as well as a photo that shows the original setup on arrival from the previous owner.

Here's the link to the vid:

Here's the setup as it came prior to yesterdays work.
 

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Sure appears to be a bad fuel pump. I didn't catch whether the inlet or outlet was correct? Also appearance and after market items sometimes are just plain junk!! Lots of offshore items that look correct but are not. The group here is great at identifying what to buy and generally where.

TonyD
 
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Take the inlet hose off the pump, use a remote starter switch hooked to the solenoid and place a finger over the inlet of the pump. Crank the engine over for a couple seconds with the key off. You should feel it pulsing. If it doesn't the pump is likely bad. If it does, drop a length of fuel line into a gas can of fresh fuel and crank it over a bit. That should get you some fuel into the filter. Sometimes mechanical pumps need to be primed with fuel to wet the check valves to start pumping.

TBH, I wouldn't be surprised if the new fuel pump is bad. The Precision pumps from O'Reilly are notorious for being bad out of the box - either inoperative, or with way too much pressure. I've had excellent luck with Carter pumps. They're stupid cheap, so much so that I always have a spare on the shelf.

https://www.rockauto.com/en/catalog...l+302cid+v8,1132849,fuel+&+air,fuel+pump,6256
 
Take the inlet hose off the pump, use a remote starter switch hooked to the solenoid and place a finger over the inlet of the pump. Crank the engine over for a couple seconds with the key off. You should feel it pulsing. If it doesn't the pump is likely bad. If it does, drop a length of fuel line into a gas can of fresh fuel and crank it over a bit. That should get you some fuel into the filter. Sometimes mechanical pumps need to be primed with fuel to wet the check valves to start pumping.

TBH, I wouldn't be surprised if the new fuel pump is bad. The Precision pumps from O'Reilly are notorious for being bad out of the box - either inoperative, or with way too much pressure. I've had excellent luck with Carter pumps. They're stupid cheap, so much so that I always have a spare on the shelf.

https://www.rockauto.com/en/catalog...l+302cid+v8,1132849,fuel+&+air,fuel+pump,6256
Nice. I may grab one just to keep in the inventory. I got the old one out yesterday...bit of a fiasco...and found a new hard line to run up to the carb, as the old one was not only stripped but, so corroded it wouldn't move. So I removed the pump and the hardline all together and will replace today. I spent some time yesterday trying to get the new one in, but after the issues of getting the old one out, I was a tad frustrated...and trying to maneuver the new one in...not lining up, then turning the engine manually to get it so slide in properly...was pushing my last nerve. Damn thing would not go in...so I took a breather and will attempt it again today. Hopefully I can get it in...and further hoping this at least starts getting gas back into the engine.

Ultimately I do believe that "newish" pump he had in there was not operating. When I took it off yesterday and disconnected the main fuel line into the pump, there was not even a drip of excess gas from the hose or the pump. Meaning when I reconnected everything and tried cranking it repeatedly, there was no fuel being pulled into the pump at all. So...hopefully getting the new one in today will yield at least that victory. Even if it doesn't improve the running performance. At least I'll have the comfort of knowing I've addressed all the fuel-related issues...checked all the vaccum issues...and checked all my connections. At that point, all eyes will be on the carburetor.
 
Sunday update: So I may be quiet on the updates for the next week as I've had to rethink my gameplan a bit. Got pretty frustrated last night and most of this morning, as I cannot get the new fuel pump back in. No matter what I attempted (including turning the engine manually to properly position the pump in...it just wasn't going. I spent about three hours combined f'ing with that thing and I'm out of patience and ideas. So, I hooked the electric pump back up..she started immediately...and I am going to take her into the shop (classic car specialist) and have him do a complete diagnostic and punch list. I have a feeling ultimately, that there is going to be a rather long list of things to do, which will at least give me an idea of what needs to be done, what should be done, and what will have to be done. Plus a rather realistic list of what my capabilities can handle on my own versus what is beyond my wheelhouse and the pros will have to handle. That seems like the more logical approach at this point. Determine all the issues, then tackle them accordingly.

So, next update probably won't be until I get it back in a week. More to come at that point.
 
Satruday morning update guys. Easier for me to just video stuff and show you what I am talking about. Attached is the update, as well as a photo that shows the original setup on arrival from the previous owner.

Here's the link to the vid:

Here's the setup as it came prior to yesterdays work.

Good Job on the video
 
Sunday update: So I may be quiet on the updates for the next week as I've had to rethink my gameplan a bit. Got pretty frustrated last night and most of this morning, as I cannot get the new fuel pump back in. No matter what I attempted (including turning the engine manually to properly position the pump in...it just wasn't going. I spent about three hours combined f'ing with that thing and I'm out of patience and ideas. So, I hooked the electric pump back up..she started immediately...and I am going to take her into the shop (classic car specialist) and have him do a complete diagnostic and punch list. I have a feeling ultimately, that there is going to be a rather long list of things to do, which will at least give me an idea of what needs to be done, what should be done, and what will have to be done. Plus a rather realistic list of what my capabilities can handle on my own versus what is beyond my wheelhouse and the pros will have to handle. That seems like the more logical approach at this point. Determine all the issues, then tackle them accordingly.

So, next update probably won't be until I get it back in a week. More to come at that point.
So sorry you are having these issues with installing the new fuel pump. While installing a new fuel pump is a little tough while laying on your back or on a creeper. I have done both and it can be tough. I always put a little oil, grease, vaseline on the metal stem that rides on the camshaft lobe level or push rod.

Most mechanical fuel pumps are driven by the camshaft. There is a lever that extends out of the pump which in turn either rides directly on a camshaft lobe, or in some cases there is a push rod between the lobe and pump lever.

You should feel some pressure when you are positioning the new fuel pump onto it's place on the side of the engine block.

I wished I lived closer to you, cause I would be glad to try and assist you with this process.

Keep us updated.
 
So sorry you are having these issues with installing the new fuel pump. While installing a new fuel pump is a little tough while laying on your back or on a creeper. I have done both and it can be tough. I always put a little oil, grease, vaseline on the metal stem that rides on the camshaft lobe level or push rod.

Most mechanical fuel pumps are driven by the camshaft. There is a lever that extends out of the pump which in turn either rides directly on a camshaft lobe, or in some cases there is a push rod between the lobe and pump lever.

You should feel some pressure when you are positioning the new fuel pump onto it's place on the side of the engine block.

I wished I lived closer to you, cause I would be glad to try and assist you with this process.

Keep us updated.
Thanks Bill. I've replaced these before on other vehicles and while it is a touch and feel process, I never had one as stubborn as this. I did put a little grease on it and did try to maneuver it in place while manually turning the camshaft. Unfortunately I can't access it from standing above, as its positioned pretty much under the platform that the AC unit was on, so yeah...was on my back...on the creeper...and even had a buddy turn the engine while I was underneath. She simply wouldn't go in. You know the drill...it's frustrating when you have one relatively simple project that shouldn't be that difficult to execute, but winds up putting a stop to the entire process. We'll see what the shop says. As I mentioned, I am sure there will be a list of things that need to be addressed. Hopefully considering it appears to be in decent running condition...the list won't be as bad as my anxiety says its going to be.
 
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