Hot start/Timing relation
Thread Starter
Drifting
Joined: Nov 2013
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From: Dublin Ohio
Hot start/Timing relation
I drove my car yesterday not knowing it was around 90 degrees (no humidity, it was actually comfortable outside) and when got to where I was going , 20 minute drive, I felt a little drop in rpm, let's call it a sputter, when I pulled in the parking lot.
45 minutes later I started it with pedal to floor, no pumps, because I had flooding issues before I sent the carb to Lars but this was the hottest it had been since.
It started right up and ran for 10 seconds but even with trying to keep the idle up until it smoothed out it still died and the wouldn't restart.
It would turn over very fast, just wouldn't fire.
Got out and took the air cleaner lid off and there was a small stench of gas (of course?) and I let it air out for about a minute.
Got in the car and it started but it blew some white smoke that smelled like gas out tailpipe and after that it ran fine but when driving home if I would hit the brakes hard the RPMs would dip to 500 then raise back up to normal 800 idle.
My timing is advanced. It runs great. No pinging. Not sure the actual number though.
So, since 90% of carb issues is timing, COULD all of this have been different if I retarded the timing?
45 minutes later I started it with pedal to floor, no pumps, because I had flooding issues before I sent the carb to Lars but this was the hottest it had been since.
It started right up and ran for 10 seconds but even with trying to keep the idle up until it smoothed out it still died and the wouldn't restart.
It would turn over very fast, just wouldn't fire.
Got out and took the air cleaner lid off and there was a small stench of gas (of course?) and I let it air out for about a minute.
Got in the car and it started but it blew some white smoke that smelled like gas out tailpipe and after that it ran fine but when driving home if I would hit the brakes hard the RPMs would dip to 500 then raise back up to normal 800 idle.
My timing is advanced. It runs great. No pinging. Not sure the actual number though.
So, since 90% of carb issues is timing, COULD all of this have been different if I retarded the timing?
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From: Virginia
You should find out the actual timing number. Did you follow @lars' instructions for timing when you got the carb back? I would also check the engine temperature with a infrared thermometer shot at the upper radiator hose.
Get a baseline before you change anything. If your issues are due to high running temperatures causing vapor lock, retarding the timing is likely to make it worse, not better.
Get a baseline before you change anything. If your issues are due to high running temperatures causing vapor lock, retarding the timing is likely to make it worse, not better.
Thread Starter
Drifting
Joined: Nov 2013
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From: Dublin Ohio
Long story short I had it a dealership that has a corvette guy. He found the distributor was not "aligned?" right (I had paid a guy to change it to HEI and then back to original) so he set the timing to what the emissions label said and adjusted the fuel and air screws.
When i left the dealership it was so sluggish it accelerating it was embarrassing so when I got home I nudged the timing up, knowing what my starting point was.
But I'll order a timing light.
Any suggestions on which one to get?
When i left the dealership it was so sluggish it accelerating it was embarrassing so when I got home I nudged the timing up, knowing what my starting point was.
But I'll order a timing light.
Any suggestions on which one to get?
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Joined: Mar 2017
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From: Virginia
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Is my vette stock?? HAHA
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From: Im not allowed to tell you
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It’s the fuel boiling, I had lots of issues, then added a 1 inch phenolic spacer and it went away. Now 1 inch is probably overkill and some folks don’t have the space for it. I would look for threads on fuel boiling and carb flooding on hot days, then see what the shortest spacer that works is. With ethanol it may be as thick as a half inch.
Another issue that could happen, but is an over night issue is the boil weeping gas through the case, but like I said that’s usually over night and is not heat dependant
Another issue that could happen, but is an over night issue is the boil weeping gas through the case, but like I said that’s usually over night and is not heat dependant
Thread Starter
Drifting
Joined: Nov 2013
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From: Dublin Ohio
It definitely boiled before I had the carb gone through.
Also found a heater hose touching the fuel pump to carb line.
This is the first time I've had this issue since I did those two things.
It's also the first time I've driven in 90 degree weather. I feel like I should have apologized to my car.
But the fact that it started up and then was so close to restarting made me think about timing because it does take a couple seconds to fire on a cold start versus instantly when I had the timing retarded.
Also found a heater hose touching the fuel pump to carb line.
This is the first time I've had this issue since I did those two things.
It's also the first time I've driven in 90 degree weather. I feel like I should have apologized to my car.
But the fact that it started up and then was so close to restarting made me think about timing because it does take a couple seconds to fire on a cold start versus instantly when I had the timing retarded.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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Maybe it’s something as easy as the choke isn’t opening all the way and it’s flooding that way. Maybe it’s that?
Thread Starter
Drifting
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From: Dublin Ohio
Originally Posted by Bikespace
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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I ground on the nearest ground and take power from my alternator post. Then of course the inductor lead goes on number 1 wire. I just try and push the other wires away so there's no cross talk
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From: Virginia
https://csr.innova.com/Content/Manua...ual_5568_E.pdf
Thread Starter
Drifting
Joined: Nov 2013
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From: Dublin Ohio
Originally Posted by Bikespace
Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,806
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From: Dublin Ohio
I bought a timing light. It's just a timing light. Nothing fancy.
Anyway, I look at the timing tab and it goes from 8 before to 8 after.
With a basic light how do you even tell what your timing is beyond 8 advanced?
Do I need to make my own marks on something to be able to simply check my timing?
First timer. Except I think I watched dad use a timing light 35 years ago.
Anyway, I look at the timing tab and it goes from 8 before to 8 after.
With a basic light how do you even tell what your timing is beyond 8 advanced?
Do I need to make my own marks on something to be able to simply check my timing?
First timer. Except I think I watched dad use a timing light 35 years ago.
Race Director
Joined: Mar 2017
Posts: 11,906
Likes: 4,479
From: Virginia
I bought a timing light. It's just a timing light. Nothing fancy.
Anyway, I look at the timing tab and it goes from 8 before to 8 after.
With a basic light how do you even tell what your timing is beyond 8 advanced?
Do I need to make my own marks on something to be able to simply check my timing?
First timer. Except I think I watched dad use a timing light 35 years ago.
Anyway, I look at the timing tab and it goes from 8 before to 8 after.
With a basic light how do you even tell what your timing is beyond 8 advanced?
Do I need to make my own marks on something to be able to simply check my timing?
First timer. Except I think I watched dad use a timing light 35 years ago.
Otherwise, you will need to mark your harmonic damper. For example, with MSD 8985 tape.
Here's a video that may help. They use the same MSD tape.
Last edited by Bikespace; Jun 9, 2020 at 06:05 PM.
1967 Pedal Car Champion
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Rabbit trail question... why are you so concerned about temperature? 90 isn't all that hot in the scheme of summertime temps. Just curious where the cautiousness comes from.