View Full Version : Engine Starting Problem


SFCamaro
Nov 10th, 06, 06:26 PM
My '67 RS/SS 350 won't start. Was running fine. I parked it in my friends garage which has an incline downwards. So the front of the car is higher than the rear. Maybe about a 25 to 30 degree incline. Don't know if that has anything to do with it not starting. When I shoot starter fluid into the carb, the engine starts up then dies. So I know I've got spark. Not so sure about gas, but I filled the tank to about 3/4 full and it still won't start. Fuel pump looks fairly new.

I was thinking of taking the rubber intake hose off of the bottom of the fuel pump and putting another 3 foot length of hose on which would lead to a plastic gas container. Then see if it starts. That would tell me there's a blockage somewhere in the line before the pump, right? The car has been in storage for a while, so maybe the pickup hose is clogged inside the tank? Oh, I guess I should make sure to put a clamp on the rubber hose connected to the fuel line that leads back to the tank, after I remove it from the pump. Don't want any explosions.

Any other steps I should take to get my Camaro starting again?

Thanks!

DjD
Nov 10th, 06, 06:48 PM
Why don't you roll it backwards out of the garage to more level ground and then try and start it. I suspect the car sat long enough to drain the lines back to the tank and now your fuel pump is sucking air. If you have a holley carb you can fill the float bowls through the vent tubes for a better prime than starter fluid. Hope your tank didn't drain out due to the steep floor in the garage.

SFCamaro
Nov 10th, 06, 06:57 PM
Wish I could roll it back, but a couple problems there as well. The right side of the car is right up against a wall. Left side has plenty of clearance. I need to start it, move it up the incline (garage is a four car long and narrow tandem garage) and re-align it. Also, my brakes are power brakes and don't work that well. I think I need a new Master Cylinder. So....can't roll it backwards. The car has only been sitting about a week in this position. It was running and starting fine before.

I've got the original Rochester Quadrajet. Can I do the same thing with it?

Maybe I should put a MityVac vacuum pump on the hard fuel line leading back to the tank and see if I can suck gas through the line? At least that would tell me there is no blockage in the tank or somewhere between the tank and the pump?

dnult
Nov 10th, 06, 07:52 PM
One thing about mechanical fuel pumps on carberated motors, once you do get it sucking fuel again, it will take several cranks to get the bowls full enough for the engine to run well. If it's a Holley, I'd pull the site plugs on the carb and see if the bowls are low. If so top them off by drippling gas down the bowl vent (not the site plugs).

I also think your idea of a hose in a gas can is a decent idea, but perhaps more work (and risk) than some other things you can try first. But at some point, I'd give it a shot. You might try running a hose from your pump into a container to see if it pumps while cranking. I have poured gas down the line to the pump (up stream so to speak), and it wets the pump enough to prime it.

DjD
Nov 10th, 06, 08:46 PM
I firmly believe since the engine fires on starting fluid it will run once you get gas to the carb. How about jacking up the back end with a floor jack? CAUTION CHOCK THE FRONT TIRES before doing this so the car doesn't roll backward at you and into the wall. If you are careful you can even move the back of the car away from the wall...

SFCamaro
Nov 10th, 06, 11:44 PM
Well, if the fuel pump checks out. I guess I'll try jacking up the back end. Although it's a fairly steep incline. One thing I tried was letting all the air out of the front tires to lower the front end a bit. Was hoping for the best, but no go, it still didn't start.

Could there be an air bubble in the line between the tank and the pump? If so, would putting a hand operated vacuum pump (Mityvac) on the rubber line going to the base of the fuel pump, help draw out the air? Guess it coudn't hurt, eh?

SFCamaro
Nov 11th, 06, 12:17 AM
Oh, one thing I forgot to mention. My fuel warning light always stays lit. Even when the car was running and I had at least 5 gallons in the tank, the fuel light would stay on. Maybe just a bad float in the tank? Could that be somehow related to the starting problem?

SFCamaro
Nov 29th, 06, 10:21 PM
So I made some progress today on my engine starting problem. I disconnected the inlet hose from the fuel pump and connected a vaccuum pump to it. Yep, I got fuel, so there's no blockage in the line from the pump back to the tank. Then I connected a piece of hose to the inlet side of the pump and disconnected the steel outlet line that goes to the carb. I blew through the hose and gas flowed out of the pump. So not a blocked pump.

I did try blowing through the inlet hose at the pump with the steel line still connected to the carb and it felt a bit hard to blow on. Not sure if that's to be expected.

At this point, I'm thinking it might be some crap in the inlet filter at the carb. Filter probably has 5 miles on it, same with the carb and pump. Everything is new. But....the car was stored for many years and the tank was never cleaned. So maybe there's some stuff in the filter?

I tried pouring a couple of ounces of gas down the primaries of the carb to prime it. The engine started for about a second or two, then died as soon as it used up all the gas. Thought that would get things flowing, but no such luck.

If it's not the filter. I'll try replacing the pump, just to be sure. But that back nut securing the pump looks pretty tough to get at. Any tips on removing that rear nut? I've got a darn a/c compressor in the way as well.

Thanks!

red67camaro
Nov 29th, 06, 11:52 PM
Try disconnecting the fuel line from the carb inlet, connecting a rubber hose from the fuel line into a catch can, and cranking the engine. If you get fuel pumping into the catch can, your fuel pump and supply system is at least good enough for the car to start and the problem is in the carb. If there is no fuel being pumped, from what you have already tested, you need a fuel pump.

SFCamaro
Nov 30th, 06, 12:18 AM
Thanks. I'll give that a try, though I'm having trouble loosening the hard fuel line from the inlet filter nut at the carb. I put a 1/2" wrench on the fitting nut and a big wrench on the filter nut. But it's on way too tight. Won't budge. I'm afraid it may be stripped and if I loosen it, yikes, i'm in even bigger trouble.

Everett#2390
Nov 30th, 06, 04:25 AM
So I made some progress today on my engine starting problem. I disconnected the inlet hose from the fuel pump and connected a vaccuum pump to it. Yep, I got fuel, so there's no blockage in the line from the pump back to the tank.Did you smell the gas? If it smelt old & sour, then you might want to drain the tank and replace with fresh fuel. Then I connected a piece of hose to the inlet side of the pump and disconnected the steel outlet line that goes to the carb. I blew through the hose and gas flowed out of the pump. So not a blocked pump.

I did try blowing through the inlet hose at the pump with the steel line still connected to the carb and it felt a bit hard to blow on. Not sure if that's to be expected.

At this point, I'm thinking it might be some crap in the inlet filter at the carb. Filter probably has 5 miles on it, same with the carb and pump. Everything is new. But....the car was stored for many years and the tank was never cleaned. So maybe there's some stuff in the filter?

I tried pouring a couple of ounces of gas down the primaries of the carb to prime it. The engine started for about a second or two, then died as soon as it used up all the gas. Thought that would get things flowing, but no such luck.

If it's not the filter. I'll try replacing the pump, just to be sure. But that back nut securing the pump looks pretty tough to get at. Any tips on removing that rear nut? I've got a darn a/c compressor in the way as well.

Thanks!I would wager the needle valve is stuck in the closed position. You might smack the carb body with a large plastic screwdriver handle, something to shock the body and not mar it at the same time.

You should be able to blow into the fuel inlet of the carb and maybe feel it come out the vent tube. If air doesn't blow through, then its clogged, pump won't pull/push any fuel.

You have mentioned later the flare nut to inlet filter is tight. My advice is position the wrenches so as you squeeze your hands, the nuts loosened. Do it quick and no rounded nuts. Better to get a tubing wrench for the fuel line. The tubing wrench grasps all six corners vice two with an open end wrench.

When you do get the filter off the carb, you might spray some cleaner or WD40, Rust Buster, etc., into the fuel inlet to help loosen the needle from its seat.

mark67ss
Nov 30th, 06, 06:44 AM
I am sorry but I really think the problem lies in the fact that the car is parked on a steep incline. Having your car in this position is pulling fuel away from the bowls which is the reason why you cannot get the car to stay started. I dont believe it is the fuel pump. I know you are looking for other causes but dont overlook the obvious. You could be spending alot of time and effort looking in places that dont need to be addressed. Jack up the rear or find a way ANYWAY to get that car on level ground. Hit it with starting fluid and see if it makes a difference. I think you will see this is the problem.

Goodluck

Mark
TOOFUN

SFCamaro
Dec 5th, 06, 11:00 PM
Well, I found the problem. Actually my mechanic did. The rod that pushes on the fuel pump lever is...BENT! So the fuel pressure is too low. Engine would start after a few tries on level ground, but on a steep incline not enough pressure to get the fuel up to the carb.

Anyone know what would cause this rod to be bent? More importantly, where can my mechanic buy one? He says he's going to have trouble finding a part like this.

How difficult is it to replace this rod?

Everett#2390
Dec 6th, 06, 06:27 AM
Push rod can be purchased from GM dealer, Group 3.935.
Lightened push rods, hollow, are marketed by Moroso and another company, brain fade, sorry, and sold by Summit Racing & Jegs, or your local speed store.

Probably bent due to high rpm's or stuck fuel pump arm either by mechanical damage or hydrolock.

Remove fuel lines, remove fuel pump and plate, remove/pull out rod, and reassemble.

69mkitmine
Dec 6th, 06, 01:22 PM
There are two bolts that come into the block from the front of the engine. one of these bolts, if long enough, can contact the fuel pump pushrod. If, when you pull the fuel pump, the pushrod falls down and moves freely, then this is probably not an issue.