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onetrick56's 1964 Grand Prix

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Hey guys, so I'm having a couple of issues. Or it may be 1 I'm really not sure. The 428 was running good but the vacuum was lower than what I thought it should be 7-8 in park and 4-5 in drive. I do have a small cam but I wouldn't think it should effect it that much. So I tried retuning the carb (edelbrock 1411 750cfm) to get more vacuum. was able to get as high as 8 in park, 5 in drive. Also I had issues with the motor holding prime. When its was running it was fine. When you shut it off you can see the fuel slowly creeping back down the fuel line and big air bubbles coming up it. Oh I put on a clear fuel line for now so I could as what was going on. No wet spots on the driveway either. So I figured that was a problem with the pump. 2 Days ago I replaced the pump, still doing the same thing. Yesterday I went out to give it another try. I use starting fluid to get the engine turning enough to pull fuel up and got it to the carb but she wouldn't run on her own. As soon as you take your foot of the pedal she dies. I forgot to mention, when she was running I had to set the RPM's between 1100- 1200 in park and in gear they would drop to 450- 550 RPM's. If I set it as say 800RPM's in park she would try to die when shifting to drive or reverse. The carb was rebuilt last year and everything on the car has been rebuilt or is new. Any thoughts?

Thank you

Edited by Wrongway
Added the RPM section
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Sorry for the delay in responding. Took my son camping this weekend. Thanks Indian, I will check the fuel line tomorrow with the can. How do I check the vac pressure relief valve? As far as cam goes, here's the cam card. I wouldn't think that it would be big enough to drop the vac.

Thank you agian

IMG_6411.JPG

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22 hours ago, Wrongway said:

Sorry for the delay in responding. Took my son camping this weekend. Thanks Indian, I will check the fuel line tomorrow with the can. How do I check the vac pressure relief valve? As far as cam goes, here's the cam card. I wouldn't think that it would be big enough to drop the vac.

Thank you agian

IMG_6411.JPG

For a 428, no that is not a big cam. Vac should be, with good rings, valves etc. a 19” to 21” motor. So after the fuel is figured out we’ll tackle the vacuum issue! 
In the mean time, what, if anything was the last thing you did to the motor?

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Ok so with the fuel line in the gas can nothing changed. Using starting fluid I was only able to get fuel up to about where the arrow is and it still had random big (1 1/2" - 2") air bubbles. 

As far as the vac goes Indian, this has been an issue since I rebuilt the engine last year. I've tried adjusting the carb and changing the timing. The rings are new and I've got less then 100, probable closer to 50 miles on her. The vac has been this way from the beginning. Not sure if this matters or not, but I'm using the factory vac gauge for these reading's.

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Staying on the fuel problem. I assume the gas can is connected to the fuel pump. Could the diaphragm be damaged and it is not generating sufficient fuel pressure to feed the fuel bowls? If this is a re-buildable fuel pump, a simple repair kit is all that is needed.Otherwise may be the fuel pump needs to be replaced.

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Hey Frosty. Yes, I've got a piece of 6' hose going from the full gas can to fuel pump inlet side. I replaced the fuel pump last week when it started doing this. Its a non rebuildable car quest brand pump. I've also got the return side of the pump blocked off right now to see if that would help, it didn't.

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Ok so here's the set up I tried. IF I did this right. lol, it still would not start. I did siphon gas out the line all the way to the carb. Disconnected the inlet and return line from the pump. Disconnected the line from the pump to the carb at the carb and connected the hose from carb to can. It did not start, used either but no fuel came out. Stroking the throttle without trying to start the engine and I cant see any fuel squirting into the carb. 

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wrongway, can you look down the carb pull on the lever and see fuel squirt down the throughts ?

 on the primarys ( front )

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11 hours ago, Wrongway said:

Ok so here's the set up I tried. IF I did this right. lol, it still would not start. I did siphon gas out the line all the way to the carb. Disconnected the inlet and return line from the pump. Disconnected the line from the pump to the carb at the carb and connected the hose from carb to can. It did not start, used either but no fuel came out. Stroking the throttle without trying to start the engine and I cant see any fuel squirting into the carb. 

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Ok then! We need to continue and find a resolution to this issue before moving on! 
leaving the pump out of the equation, let’s test the carb. Get a small syringe or very small funnel and fill the carb through the air horn vent tube, see pic! When the bowl is full some fuel will come out of the tube, that’s ok! Then pull the accelerator back as Kiwi suggested and see if the accelerator pump squirts fuel. If it does try to start the car as normal. If it runs, let run till it dies. Fill it again and repeat.
Also I see as I’m writing this JustA has answered, so try what he says as well! That well prove whether or not the fuel pump works! 

If the pump works and the carb takes fuel through the air horn and fires! Your problem is with the carb, most likely the float! If it won’t fire it is still most likely the carb, but the jets are blocked! Both may be due to today’s fuel! Alcohol in fuel wreaks havoc with fuel systems and carbs if you don’t use additives to get rid of the alcohol! Sorry it’s just a fact of life today. 
FYI if there’s a question as to the vent tube it’s the small tube that is slant cut at the top portion of the carb air horn.

B5337B7B-729F-4113-85F1-EA681A4E7B7C.jpeg

Edited by Last Indian
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Ok I'm going to go run these test now. Ill get back to y'all in a couple of hours. The carb is an edelbrock 1411 750cfm Justa, not sure if it matters or not but I ran an aluminum line from the pump, under the intake, on top of the valley pan, in front of the distributer when I was putting her together. Then connected the clear hose to the aluminum hose and to the back left side of carb to where it connects. I ran under the intake trying to clean up the looks. Wasn't sure if the heat would affect it or not. The clear was ran a week or so back so that I could see what was going on. If y'all think that was a bad idea I can move them.

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Ok, so I DO have fuel squirting when I gravity feed and got the car running that way. I hooked up to pump with hose in the gas can. I get a trickle of fuel then nothing. I know this is gonna sound crazy but, when I tried to siphon fuel from the carb end of the hose through the pump and into the can I’m still getting bubbles in the line. I did siphon fuel up to the carb by mouth after filling carb, connected the hose to carb and started. It ran till the carb went dry. Never pulled fuel into the filter. 

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faulty fuel pump Wrong way:cheers: change it out and try again👍

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21 minutes ago, Wrongway said:

Ok, so I DO have fuel squirting when I gravity feed and got the car running that way. I hooked up to pump with hose in the gas can. I get a trickle of fuel then nothing. I know this is gonna sound crazy but, when I tried to siphon fuel from the carb end of the hose through the pump and into the can I’m still getting bubbles in the line. I did siphon fuel up to the carb by mouth after filling carb, connected the hose to carb and started. It ran till the carb went dry. Never pulled fuel into the filter. 

Let me make sure I understand what you said! Carb full of fuel, the engine started and ran till the carb ran out of fuel, right? Then with the fuel pump no real pumping of fuel, right?

if that is correct than I have to go back to what I said before! Either the push rod from the cam to the fuel pump lever is the wrong one and to short, the fuel pump, doubtful, but needs checked is the wrong one so the lever isn’t the right length or the eccentric on the cam is bad or the cam is somehow not right! What I see and by what I think you are saying about what’s happening is this. The pump never real gets fuel filled in it! Which means the majority of the space is air and since it can’t pull fuel into the fluid side of the diaphragm air from the outlet side re-enters that space, thus the air bubbles. 
Next two things to do. Take the pump off take out the push rod and measure it, then you need to find out what the correct measurement is for the right rod for your motor! Also if you have a vise hold the pump in the vise. Connect a hose to the inlet side of the pump the other end of the hose put in the gas can or any liquid for the matter. On the outlet side take a hose run it to a bucket can whatever! Now push the fuel pump lever by hand repeatedly see if it will pump the fluid through the pump! If so, the problem is definitely the pump, the push rod or the cam!

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Ok so yeah you’ve got it right bro. I’m not sure about it being the cam or rod because it was running up until a couple of weeks ago. So if it is the rod or the eccentric would an electric fuel pump And block off plate solve the fuel issues? 

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2 minutes ago, Wrongway said:

Ok so yeah you’ve got it right bro. I’m not sure about it being the cam or rod because it was running up until a couple of weeks ago. So if it is the rod or the eccentric would an electric fuel pump And block off plate solve the fuel issues? 

Short answer, yes! Long answer it would depend on what if anything was damaged! Pull the pump & rod! Inspect the rod for damage/wear/galling. Did you break in the cam correctly, use the right break in lube, just covering bases here! But somethings changed by what you’re indicating!

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Ok, so my parts guy is sitting here with me. He hangs out here sometimes and tinkers on stuff with me. He just told me that when he ordered THIS fuel pump, (I warrantied out the old one last week) that he could not find one for my engine. My 428 cam out of a 68’ Grand Prix, so he ordered one for a 68’GTO. He thinks it was for a 400. He says the part numbers were the same so he figured that it should work. He also said he ordered the one with no return line. The one he gave me was one with a return line. Not what was on the box. Could that be the problem??

I broke it in per comps instructions. But since there’s only 50- 100 miles on it I’m not sure you could really say it’s broke in. Lol. Yes I used Comp lube to break it in also

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21 minutes ago, Wrongway said:

Ok, so my parts guy is sitting here with me. He hangs out here sometimes and tinkers on stuff with me. He just told me that when he ordered THIS fuel pump, (I warrantied out the old one last week) that he could not find one for my engine. My 428 cam out of a 68’ Grand Prix, so he ordered one for a 68’GTO. He thinks it was for a 400. He says the part numbers were the same so he figured that it should work. He also said he ordered the one with no return line. The one he gave me was one with a return line. Not what was on the box. Could that be the problem??

I broke it in per comps instructions. But since there’s only 50- 100 miles on it I’m not sure you could really say it’s broke in. Lol. Yes I used Comp lube to break it in also

The return could be an issue not sure how the valuing is setup internally. So I think possibly you could try this to see if it makes a change. Open the return outlet, fit it with a fitting and run it to a can. 
If you ran the cam 15-20 minutes at 2000 rpm it’s broke in!

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Ok I’m getting ready to put the pump in the vice but I just found this. To me I can’t see how the line would seal to the fittings flare. I would think it could/would let air in the line. What do you think?

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55E96773-30F1-4924-B78D-065434497A99.jpeg

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The black hose is the gas tank and the clear is the carb side

 

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2 hours ago, Wrongway said:

Ok I’m getting ready to put the pump in the vice but I just found this. To me I can’t see how the line would seal to the fittings flare. I would think it could/would let air in the line. What do you think?

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No! You need a flair fitting & that’s not a flair fitting. What happens if you leave the other line you have block open? Go to NAPA see if they can get you the correct pump. Not all parts are interchangeable, so there may be enough of a difference between the two pumps that’s causing the problem.

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The blocked off line is then return line. I unblocked it and pumped it again after I sent that video. While it’s pumping out of the clear hose I get a small stream of fuel out of it also. Ok, I’ll get the flare fitting and different pump. Could that fitting have been pulling air in and causing the problems?

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6 minutes ago, Wrongway said:

The blocked off line is then return line. I unblocked it and pumped it again after I sent that video. While it’s pumping out of the clear hose I get a small stream of fuel out of it also. Ok, I’ll get the flare fitting and different pump. Could that fitting have been pulling air in and causing the problems?

That’s the pressure side of the pump! So it could cause the leak down, but I would expect it to also leak fuel when it pumped fuel. So it’s a little iffy. It might leak air and not fuel, but without being there I can’t say.

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9 hours ago, Last Indian said:

Short answer, yes! Long answer it would depend on what if anything was damaged! Pull the pump & rod! Inspect the rod for damage/wear/galling. Did you break in the cam correctly, use the right break in lube, just covering bases here! But somethings changed by what you’re indicating!

last indian, your bang on the money mate! if that rod was not lubed, it would take 100 miles to kill the end of it and or the lobe !:cheers:

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