# 67 gto fuel pump,lines, starter questions



## 42willys (Sep 19, 2013)

Hi 
I have a 67 GTO 400 h/o 
1. how or where does the fuel return line from the (blue) fuel filer bolted to the intake before the carb, connect to at the bottom(diagram??)
2. if above is to the pump, where does the return line to the tank go
3. should the fuel pump have 2 fittings or 3
4. what pressure should the fuel pump be putting out, I have an after market Chinese one and I seem to get over pressure and I get fuel pushing past the carb needle and it floods the car when I shut it off.
5. unrelated...any suggestion on a mini or high torque starter?
my o/e gets heat soaked and will not start. I have a external solenoid
on it now( I won't call it a ford relay butttt) 

thanks!!


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## Matthew (Feb 11, 2011)

Assuming you have a 67 engine with a 67 fuel pump, your pump would have two fittings. There is only one line running from the tank to the fuel pump. The pump should be putting out about 6 PSI. The pump is mechanical, so it will not produce pressure when the car is shut off, so your flooding problem is probably not from the pump. 

I have not used a high torque starter, so no help for you on that one. Matt


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## Colorado67GTO (Sep 11, 2014)

Hello Matt. I have interest in your reply. I recently removed my fuel lines from my 67 and I had two lines. It definitely looked stock. I can post pictures as needed. I don't want to question an expert, but I guess I am


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## chuckha62 (Apr 5, 2010)

I have to respectfully disagree with Matt. In my experience there is a VERY strong chance your aftermarket pump is causing your flooding. The factory Quadrajet carburetor was designed for only about 5.5 to 6 psi of fuel pressure, max. IF (notice the big IF) your fuel pump were properly calibrated to 6 psi, you wouldn't likely have a problem. Most aftermarket pumps put out considerably more than that however and the pressure could be staying high immediately after the engine is turned off. It should bleed down fairly quickly after that.

Holley Carburetors tend to be be more fuel pressure tolerant than Carters or Rochestors (or Fomoco, for that matter). You may very well benefit from spending a little more for a properly calibrated fuel pump.


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## geeteeohguy (Feb 2, 2008)

'67's that came with HD cooling had the return line coming from the filter to the return line in the frame, which is right next to the bigger delivery line. It's a 1/4" line. The filter bolts to a bracket mounted to the Thermostat housing, and the metal 1/4" line bolts to the timing cover, running under the alternator. It connects via rubber line to the frame line. I can post a picture from my home PC later. '68 and later had the 3 fitting fuel pump. '67's used the return line 3 outlet filter, which is a better system (keeps fuel cooler). Fuel pressure should be NO MORE than 5.5-6 psi, or you WILL have flooding. 3 or 4 psi is usually adequate. No need for a high torque or mini starter on these cars if the ignition switch circuit is in good condition. Most of the 'starter' problems with these cars is, in reality, a high resistance 'S' wire from the ign switch to the solenoid. Like 95% of the time.


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## geeteeohguy (Feb 2, 2008)

As a PS there is a pic of the fuel filter/return line on my '67 on my 'home page'. Just click on my name and click on 'photo album'. I'm running a generic filter (not the $40 repop), but the brackets and lines are all correct. 
Jeff


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## Matthew (Feb 11, 2011)

I guess I learned something there. Thanks for being respectful about your disagreement. 

Chuck, I will work on my rebuttal. Matt


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## Colorado67GTO (Sep 11, 2014)

Thanks Jeff for clearing this up. So it looks like both you and Matt were correct. He said only one line FROM THE FUEL PUMP. I guess I missed that detail. 

My car was a bit of a mess. It had the return line from the fuel filter as you described, but also has 3 ports on the fuel pump with one of them capped. Obviously the fuel pump was replaced somewhere along the way with the wrong one. 

Thanks again.


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## Matthew (Feb 11, 2011)

42Willys, maybe you can describe your "flooding" situation in a little greater detail. Have you or can you check the pressure from your fuel pump? I agree with these gentlemen about the affects of a fuel pump that produces much more than 6 PSI - so that is not a debate at all. That said, you cannot point to the fuel pump, whoever manufactured it, and say that is the reason for the flooding. Function of the float and setting along with operational needle and seat, and even the type of fuel you are using all come into play. 

Not the first time on this issue of post shut down pressure from the pump. I contend there's instantaneous loss of pressure and Chuck is suggesting residual pressure, however short it might be. Regardless, there's not going to be a lot of fuel that pushes past the seated needle at the inlet even with residual high pressure. 

So... anything you can add in details? If not, change out the fuel pump with the correct PSI and see if that fixes it. Sometime the process of elimination is the way to go. I will yield the floor to Chuck. Matt


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## chuckha62 (Apr 5, 2010)

Given that there is a check valve of some sort in the pressure side of the pump to keep fuel from reversing flow, the pressure will bleed off in the easiest way possible. If the easy way (due to too much pressure) is to unseat the needle and seat in the float bowl, then flooding will result. I would think a functioning return line has to help relieve this, as well.

Chuck


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## geeteeohguy (Feb 2, 2008)

Fuel vapor return lines help prevent flooding, and really help with vapor lock issues with the new terrible gas. There is no down side to running a vapor return line, only benefits!


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## geeteeohguy (Feb 2, 2008)

I'll try to post a photo or two of my stock '67 vapor return set-up...


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## 42willys (Sep 19, 2013)

thank you to all who replied
I added the return line from the filter to the tank and the problem seed to go away.
but on to other problems


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## 67Twistytee (Feb 24, 2014)

geeteeohguy said:


> I'll try to post a photo or two of my stock '67 vapor return set-up...



Was this filter bracket a factory install? I seem to recall seeing a note that they were added by dealers. Does it simply screw into one of the thermostat bolt?


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## TinIndian68 (Mar 22, 2015)

I had a '67 LeMans that would not start sometimes for like 30 minutes after I shut it off, if I had been driving it for a while. I bought a starter solenoid heat shield - I think it was like $5 - and never had any issues again after I installed it.


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## geeteeohguy (Feb 2, 2008)

Twistee, yes, a factory install. Mine originally had the red GM filter and old funky bracket when I got the car 32 years ago. I went with a generic filter (I drive the car, don't show it) and a repro bracket. Mine is an early '67, and came with HD cooling, with the return off the filter. In late '67/early '68, the return came off the pump, and the large filter was eliminated. I prefer the early system with the large filter. The T stat has a special bolt with a stud on the head to accomodate the filter bracket.


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## 67Twistytee (Feb 24, 2014)

Interesting. I have an early build too with the return line off the filter. I still have the original red A/C fuel filter in my parts stash, but I put on a Napa Gold (think its tha same as the Wix 33041) with the return line for regular use. I've never seen that bracket until now and thought the filter just stayed in place between the hard line from the carb and the fuel pump. The bracket makes sense as it prevents the rubber connecting lines from slipping as the engine vibrates. Is there suppose to be two studs on the thermostat housing - one on the front for the alt bracket and one on the rear for that fuel filter bracket?


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