Rebuilt engine won't start
Thread Starter
Instructor
Joined: Apr 2011
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Rebuilt engine won't start
Hey all - finally got everything ready for first start up on my new rebuilt - 3 tries for 10 seconds each and no go. Turns over but won't fire - tried twice with air cleaner on and once with it off. I am concerned about causing damage if I try any further (engine has new pistons etc, cam and timing chain) - looking for any ideas
I did the following:
Coolant full and break in oil in engine and oil pump primed before first start attempt
Lined up distributor to number 1 with number one at top dead center
Double checked spark plug wires are connected correctly for firing order
Added a little gas into the venturis in the carb
Double checked all belts, hoses, fluids etc
Any ideas are welcome!
How much more can I try this before I need to be concerned about causing damage to the new parts?
Thanks
Bernie
I did the following:
Coolant full and break in oil in engine and oil pump primed before first start attempt
Lined up distributor to number 1 with number one at top dead center
Double checked spark plug wires are connected correctly for firing order
Added a little gas into the venturis in the carb
Double checked all belts, hoses, fluids etc
Any ideas are welcome!
How much more can I try this before I need to be concerned about causing damage to the new parts?
Thanks
Bernie
Drifting
Joined: Nov 2013
Posts: 1,546
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From: Scottsdale Arizona
What year? Did you verify that it’s at TDC on number 1 on the compression stroke? Are you sure the distributor is sending spark to your plugs? Are all the connections at the distributor correct? Assuming it’s HEI, is the wiring connected?
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Sorry my bad - 1979
Yes verified I am number one on TDC - I marked the harmonic balancer and when I set the rockers I watched the movement of the intake and exhaust valves - I verified that when I had valve overlap on number six that I was at TDC on number one
I am in the process of checking for spark - easy way to do this?
Not sure I understand the question about the HEI
Yes verified I am number one on TDC - I marked the harmonic balancer and when I set the rockers I watched the movement of the intake and exhaust valves - I verified that when I had valve overlap on number six that I was at TDC on number one
I am in the process of checking for spark - easy way to do this?
Not sure I understand the question about the HEI
Thread Starter
Instructor
Joined: Apr 2011
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Hi again - checked for spark which I have but not strong blue spark - faint yellow on the one I tested - going to get new plugs
HEI - I have and HEI system - by wires did you mean connectors in the top for the distributor for batt, tach etc - if so these are connected
HEI - I have and HEI system - by wires did you mean connectors in the top for the distributor for batt, tach etc - if so these are connected
Drifting
Joined: Nov 2013
Posts: 1,546
Likes: 281
From: Scottsdale Arizona
Yes, I was referring to the battery, tach connections. A faint yellow spark? How old are the plug wires, spark plugs? Is the distributor original to the car? It’s possible that the coil could be on the way out or a bad module. With the weak spark it sure sounds like it’s ignition related.
Thread Starter
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Will do - I am double checking number 1 on tdc, setting at 10 degrees before tdc - I have a faint smell of gas on the plugs I am removing but they are not wet
Any thoughts on whether I should add more gas to the carb?
Any thoughts on whether I should add more gas to the carb?
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Drifting
Joined: Nov 2013
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From: Scottsdale Arizona
Do you see a good stream of fuel when you work the throttle by hand? If you do, you may not need to add any to the carburetor. How long was the car sitting while the engine was being rebuilt? How old is the gas in the tank? I know the gas with ethanol here goes bad relatively quickly unless you add a fuel stabilizer.
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Car was sitting about 9 months - can't recall if I added stabilizer but I don't think so
I did not see any gas in the carb when I work the throttle - I checked the fuel filter and it is bone dry - so wondering if gas is the issue. I was thinking I would check the fuel pump and rod as after turning over 4 times I would expect some gas to be on that filter. Can I prime the fuel pump in any way?
Other thoughts?
I did not see any gas in the carb when I work the throttle - I checked the fuel filter and it is bone dry - so wondering if gas is the issue. I was thinking I would check the fuel pump and rod as after turning over 4 times I would expect some gas to be on that filter. Can I prime the fuel pump in any way?
Other thoughts?
Drifting
Joined: Nov 2013
Posts: 1,546
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From: Scottsdale Arizona
You won’t be able to move the rocker arm on the fuel pump very much. It seems as though if it worked before it should be ok now. A good way to test it is to disconnect the fuel line at the carburetor and crank it for a few seconds and see if you have fuel flowing. It’s best to have someone help you with this and have a container to catch the fuel. I had a similar situation with my 79 C10. It turned out that it had a pinhole in a rubber fuel line between the tank and the fuel pump. BTW, did changing the plugs make the spark any different?
Is my vette stock?? HAHA
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there is a vent tube on top of the carb, it looks like where the stud goes in . Poor a shot glass worth of fuel in that hole and then work the throttle until you see fuel squirt out the accelerator pump nozzles. The use a small squirt of engine starting fluid over pouring fuel down the carb throat. You have less of a chance of flooding it with the can of fluid
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So just tried now - no go. Changed the plugs, added some 100 ml of fuel in the carb venturis per the instructions of the machine shop crew. Felt like it wanted to start and then didn't catch. Machine shop suggesting I add a little more fuel.
Roger - Where do I squirt the engine start fluid if I go your route?
Also wondering if I should be repriming the oil pump top ensure the new parts are lubed? I ran it up to 40 psi with my drill before these start attempts but now 5 attempts
Roger - Where do I squirt the engine start fluid if I go your route?
Also wondering if I should be repriming the oil pump top ensure the new parts are lubed? I ran it up to 40 psi with my drill before these start attempts but now 5 attempts
Race Director
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From: SW Florida.
you have no spark. if you had spark engine would fired. even if timing way off, it woulda barked or popped or bucked or something. do you have a timing light? put it on a plug wire and hold trigger while somebody cranking starteer. no flash? no spark. and you won't damage anything cranking it. do you see oil pressure while cranking starter?
Is my vette stock?? HAHA
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Down the venturies. JUSt hold the chole open and give it a quick squirt it ususally gets enough by the bottom flaps. If not crack them open a hair and give it a squirt. Just pouring fuel down the venturies will usually lead to flooding it
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So partial success - got it started - working by myself - teenage son playing ball - ran for 5 minutes - I had a string on the throttle to keep idle at 2000 rpms in break in range - got out to adjust the idle speed - string slipped - operated throttle by hand and pull wide open and car stalled - won't start now - maybe flooded?
Another maybe bigger concern saw some coolant on the top of the manifold - all bolts torqued to spec - not sure where it is coming from
Another maybe bigger concern saw some coolant on the top of the manifold - all bolts torqued to spec - not sure where it is coming from
Le Mans Master
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From: melbourne florida
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Get a little squirt bottle like you see in a BBQ restaurant, assuming you have such things in the frozen tundra. Anyway put some gas in it Use the tiny funnel to pour some gas in the bowl vent. That would get gas in the bowl so you don't dump too much in.
Don't re use the bottle for barbecue sauce again unless you like that north Carolina stuff then it's fine.lol .
I agree it seems your spark is too weak.
Don't re use the bottle for barbecue sauce again unless you like that north Carolina stuff then it's fine.lol .
I agree it seems your spark is too weak.
Le Mans Master
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From: Gladstone MO
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I've had a couple the cylinders didn't have enough ring seal (new rings) to make compression. Good shot of oil into each cylinder and they fired right off. Rings were not seated at all and what little oil it was assembled with had gotten washed off as I tried to prime the carb.
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So more success and then ?
Got it started - did the 20 minutes break in - had a fan running to cool it off - temp was running around 220 - moved the fan so I could pull into garage and brought the idle down and the temp moved up to just under red line - car stalled, Coolant was clearly boiling out into overflow. I lost a little when I was running it with the cap off but I put almost 4 containers in.
Worried that I may have done damage - car was running a little noisy but I assumed that I need to tighten down one or two rockers.
Best guess on whether I have done any damage at that temp?
Got it started - did the 20 minutes break in - had a fan running to cool it off - temp was running around 220 - moved the fan so I could pull into garage and brought the idle down and the temp moved up to just under red line - car stalled, Coolant was clearly boiling out into overflow. I lost a little when I was running it with the cap off but I put almost 4 containers in.
Worried that I may have done damage - car was running a little noisy but I assumed that I need to tighten down one or two rockers.
Best guess on whether I have done any damage at that temp?