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I have a 72 Nova w/ 305 SB out of an 85 C-10 pickup. I am having problems with it bogging on acceleration very bad. The car comes as close as it can to stalling out totally. As I press the gas pedal while setting at a stop light, the car will ramp sharply and the dive even more sharply and has zero power. I pump the gas and the RPM's don’t change. If I let off the pedal totally the engine will ramp back up but if I press the pedal at all it dives again. It takes 2 to 300 yards to gain any kind of momentum. I tried dropping the car into neutral while it was bogged and the engine RPM's spike but when I drop it back in to gear it dives right back down. I have replaced most everything on the car so I don’t know where to go from here. This is my daily driver so it is hard to pull out into traffic when I can only go 10mph forever. It makes it no fun to drive when you can't get on it and show off, its more embarrassing that I hold up traffic.
 

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No accelerator pump shot? With the engine off, do you get a good squirt of fuel down the carb when you hit the throttle? Timing retarded?
 

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I do get a good shot of fuel when the car is off, I do how ever never ever get the car to start the first time it cranks over. It firs up and then dies EVERY time. I have had the timing set and I took it toa mechanic last week and verified the timing,new plug wires, new plugs, put the dielectric boots around the headers to prevent arcing, changed the vacuum advance canister, vacuum regulator on the trans, brand new Holly 500cfm carb, new plugs, all new vacuum lines, new rubber fule lines, change fuel filter, new fuel pump. The only thing left to change is the whole distributor or the fuel sending unit. Everything else is new.
 

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Does this sound like vapor lock or something to do with the power valve in the carb. I've checked a few things online about carbs and trouble shooting and dont know if my problem relates to the bowls emptying and not refilling as the accelorator is pressed. ??????? I really have no clue what to do next. Please - I'll take all the help I can get
 

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If you took it to a mechanic to "verify" your timing, what did he say it was set at? Most likely if he set it to specs, it will be quite a bit retarded from where it should be to run right. The spec on that motor is probably somewhere between 0 and 4 degrees BTDC. hey just dont run worth a damn there. Try kicking the timing up to around 12* initial and see what it does. If you verified that you have a good accerator pump charge, then I'd try advancing it and see what happens.

Also, did he check to make sure you had mechanical and/or vacuum advance?
 

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Discussion Starter #6
He said the timing was around 10, he told me SB with stock cams run best between 9 and 12, and yes he did check the vacuum advance when I was there- I had the vacuum advance hooked to the carb wrong and the advance was always engaged and he fixed that but noiw it sounds like a tractor and idles very very low. I dont have a tac so I dont know exactly where it is. This problem has really started when it began to get hotter around April or so. Pior to that it seemed to work ok I guess but I had so many other problems prior. This is my first project car so I don't have lots of know how about things so everything I do seems to be a trial and error - mostly errors but I'm learning.
 

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Fuel pressure or float level problem.

or bad vacuum leak.

Al
 

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Discussion Starter #8
Are electric fuel pumps with a regulator a good solution? The carb I bought doesnt have the screws on the side of the bowls to show where the level of fuel is. How are you supposed to adjust it without taking the whole thing apart???
 

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Are electric fuel pumps with a regulator a good solution? The carb I bought doesnt have the screws on the side of the bowls to show where the level of fuel is. How are you supposed to adjust it without taking the whole thing apart???
What carb do you have?

Also stock pump should be fine. You might just have a bad pump.
They are cheep enough to replace. 20.00 range

Al
 

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Discussion Starter #10
I've bought three fuel pumps in the process of getting the car running. It is just the stock replacement for a 72 Nova - Not the pump off the 85 engine it is on because of the extra port on the pump. I took the evaporator canister and lines and smog stuff off the car so I didn't know what to do whit the third port on the pump from 85. The pump that is on there now is about three months old.
 

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I've got a Holly 500 or 550 can't remember. I bough tit new out of the box at a local parts house.
When I let off the pedal it comes back to life - could the jets be to small??
No, jets are not the problem.

You need to give some more info on carb. (even a pic)
Part # ?

Just because the pump is new means nothing these days with the cheep parts available today.

Have you checked the fuel line from tank to pump?
Check the rubber line from the tank to the steel line. Is the steel line pinched or crushed??

This symptom has fuel pressure or float level problem all over it.

AL
 

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Discussion Starter #14
Thank you so so much for pointing me in the right direction. I would have bought everything under the sun untill I had abunch of useless parts and still have the same problems. I need to put new fuel lines in from the pump to the tank this weekend and see how that helps.

How Do you check the float level if the bowl doesnt have the window or screw port on the side??
 

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Discussion Starter #16
I got the box down from the atic and it is a 600cfm Holley Double Pump street performer, mechnical secondaries, dual accelerator pumps. Part number 0-80457S. I watched the holley video that came in the box but all the adjustments are for carbs that have adjustment screws. I did tune the idle mixture like it said and it sounds much better.

Last night I took the fuel tank down, check all my fuel lines and filters, Checked the fuel sending unit for clogs and everything checked out OK.

Is the fuel line supposed to be hot, even near the back of the car. I thought the fuel would cool the line down but it seems very hot. I can also see the fuel boiling in the inline filter.
 

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Discussion Starter #17
I can also hear the PCV valve rattling while the car is idling. Is it supposed to do this at idle and so loudly. It sounds like a rattle snake under the hood.
 

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I can also hear the PCV valve rattling while the car is idling. Is it supposed to do this at idle and so loudly. It sounds like a rattle snake under the hood.
No, and it a 2.00 part.
Replace it.
 

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Is the fuel line supposed to be hot, even near the back of the car. I thought the fuel would cool the line down but it seems very hot. I can also see the fuel boiling in the inline filter.
have you moved the battery? In trunk?

Check your grounds, engine, sub-frame & body?
I have seen the fuel line becoming the ground between the sub-frame and body when the engine to firewall ground is not being used.

Al
 

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600cfm Holley Double Pump street performer, mechnical secondaries, dual accelerator pumps. Part number 0-80457S
That part number is a 600 cfm vac. sec., not a double pumper. Did you mis-type the number? But either way they both have sight plugs (not the clear ones, but screw-in plugs)

This is the carb with the number you posted:
 
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