Firing issue

[straightlinespeed]

Just had the car to the dyno and they made a bunch of adjustments and it runs great now. With the exception of one thing.

I had to make a stop on the way home. The car sat for probably 10-15 minutes. I went to start it and it would not pop off and fire unless I held the throttle wide open.

The timing was way off. It was set at 50* and they changed it to 38*. But before I brought it to them the car would fire right off with out touching the throttle.

I called them back and the only thing they thought was that the head gaskets where leaking a little bit of water into the cylinder. I dont necessarily agree with that so just looking for thoughts on why this would be like this now.

 

[67Dart273]

If they thought the head gaskets were leaking they should have stopped the dyno tune and TOLD you that.

Timing? What timing are you referring to? total with vacuum at cruise could well be over 50*

38 is generally "plenty" under full power when vacuum has dropped off

What is the curve in the dist? What is initial? If you have a factory "not" modified/ recurved distributor, these came with a long slow curve, and NOW the initial timing may be rolled way back.

What all did "they" change?

 

[straightlinespeed]

Of course I have no idea how they adjusted the timing since I couldnt be in the dyno room. Im just going off of the sheet with the things they said they did, and it was stated they changed the timing from 50 to 38. I do know that they had the car reved up while adjusting the timing. So Im assuming it was 2-4K setting it. Sorry it was not explained. Of course I dont have a timing gun myself to see what its doing now with everything hooked up.

Sorry I cant answer the rest of your questions on the timing since I was not in there. I know after changing the timing the car picked up 7HP. So it did improve it and it does drive much better and smoother down the road now.

Im running a factory distributor (nothing special) and I asked them if there where any issues with that. They said that it was actually in good shape and didnt need to make any changes to it.

The other issues they fixed were with the Eddy carb. It was running rich at part throttle so they changed the metering rods. As well as fine tuned the carb with all the settings on it.

 

[KitCarlson]

Holding the throttle wide open is an unloading procedure when engine is flooded.. It forces the choke open, and lets more air in. Flooding, due to too high float level or fuel getting past the needle and seat, it may be also related to heat soak. Just one more possible item to consider in the investigation.

 

[straightlinespeed]

Ohhh, Vapor lock, ran into that before with a vehicle, forgot about that also. I will have to let the car cool and then check it again to see if it fires right away.

 

[TrailBeast]

Let me guess, it was a warm day and it sat for 10-15 min and it was hard to start and felt like it was kinda flooded for a min or two right?
Ran like crap after it started and then cleared up?

The Eddie carbs do that a lot, and especially with the ethanol fuel.
Carb spacers help, but don't completely solve it.
Some people swear that a fuel return line helps or solves it.

 

[straightlinespeed]

Let me guess, it was a warm day and it sat for 10-15 min and it was hard to start and felt like it was kinda flooded for a min or two right?
Ran like crap after it started and then cleared up?

The Eddie carbs do that a lot, and especially with the ethanol fuel.
Carb spacers help, but don't completely solve it.
Some people swear that a fuel return line helps or sovles it.

Yep you nailed it! I'll let you all know how it starts after it cools

 

[TrailBeast]

Yep you nailed it! I'll let you all know how it starts after it cools

They start fine after a half hour or so, at least mine does.
The new mini starter helped a lot for the actual starting, but clearing the overfueling still takes a min or so.
The mini starter (gear reduction) turns the engine a bunch faster, so the actual firing up problem isn't too bad any more.

 

[crackedback]

I hope you adjusted the mechanical advance inside the distributor?

If you had 50* total on it without vacuum, then you were on your way to hurting the engine.

Having to mat the pedal when starting is also indicative of not enough initial timing.

Put a timing light on it at idle and see where it is set. Sounds like they did the total timing deal which may well be the correct total number. It should have 16-22 is my guess, but they backed out 12ish degrees. you need to get both ends of that under control.

 

[straightlinespeed]

They start fine after a half hour or so, at least mine does.
The new mini starter helped a lot for the actual starting, but clearing the overfueling still takes a min or so.
The mini starter (gear reduction) turns the engine a bunch faster, so the actual firing up problem isn't too bad any more.

Dead on! Went out and it fired right off! Im guessing it was vapor locked.

So now for the spacers, I know there are two different styles, one with a square bore and the other with the 4 holes. Whats the difference and what do you recommend?

Another suggestion I heard of way back was to install a small inline fuel pump. Im guessing to keep constant pressure on the mechanical fuel pump.. Im not sure sure I like that idea. Thoughts on that?

 

[67Dart273]

Hot start issues is one reason I finally "went" efi. In fact just yesterday/ today I got the car running again with an improved ECU. The old system was a used Holly Commander 950 --a perfectly good working system, except it's "all manual" programming, and I don't have a second person to operate the program while I drive, nor do I want to spent days on end at a dyno shop

So I just got through buying (1400 bucks) the Holley HP computer and harness. Even without final tweeking, the car now runs much better when hot. Instant starts all the time.

So far as carbs, there's been some discussion that the Ed carbs are more prone to hot start issues because the float bowls are "down" on the manifold. Best thing I did for mine before converting was to go to a rear electric pump, installed a vapor return line, and a carb heat spacer. That all helped a "bunch."

 

[straightlinespeed]

I hope you adjusted the mechanical advance inside the distributor?

If you had 50* total on it without vacuum, then you were on your way to hurting the engine.

Having to mat the pedal when starting is also indicative of not enough initial timing.

Put a timing light on it at idle and see where it is set. Sounds like they did the total timing deal which may well be the correct total number. It should have 16-22 is my guess, but they backed out 12ish degrees. you need to get both ends of that under control.

My guess is the 38* is total timing. I took it for another drive and it runs so smooth.

The timing was initially set by my brother and we were doubting his very old timing gun.. We tried timing the car two different times and the numbers where different each time. So we just set it by ear until it smoothed out. Thats how the 50* came up. It ran well enough to get it home.

 

[TrailBeast]

Dead on! Went out and it fired right off! Im guessing it was vapor locked.

So now for the spacers, I know there are two different styles, one with a square bore and the other with the 4 holes. Whats the difference and what do you recommend?

Another suggestion I heard of way back was to install a small inline fuel pump. Im guessing to keep constant pressure on the mechanical fuel pump.. Im not sure sure I like that idea. Thoughts on that?

There are different kinds of materials also like Phenolic, wood, aluminum, fiber and even a few sandwich styles.
I have the Edelbrock fiber 5/8 thick and my car still does it.

It's not really a vapor lock as we know it, but more of an evaporation issue.
Eddies don't hold a lot of fuel, and my theory is that when you shut the car down it boils the lighter ethanol fuel so quickly that it pretty much empties the carb.
When it vaporizes the fuel, the vapor settles in the intake so when you go to start the car it sucks that vapor in and there ya go.
Now to add to that problem, we have an empty carb with causes a delay in the fuel delivery and then boils the first fuel that it does get making things worse.

I have an electric fuel pump only, from when I was chasing this problem down and it made virtually no difference, so I know that the problem is not all due to a mechanical pump or loosing a prime as some say.
I also know that it is physically impossible for the fuel to be "siphoned" back out of the carb since the float needle is above the fuel level in the carb.

Out of all the solutions talked about, the cooler fuel solutions seem to solve the problem (as in recirculating fuel systems) also called "return systems"
These pull new cooler fuel from the tank and circulate it back to the tank as long as they are on.
This delivers the cooler fuel to the carb every time the needle opens so it does not get a chance to get hot sitting in the fuel line.

Phenolic spacers and constantly circulating fuel seems to be the best solution "besides using a Holly instead of an Eddie."

 

[moper]

So just so I'm clear - the dyno tuner said a factory distributor was "fine and needed no changes" but they took out 12° of total timing? They then proceeded to tell you the reason it was hard to start hot was coolant in the cylinders as a result of the head gaskets?

Did you pay for this work?

I hope you adjusted the mechanical advance inside the distributor?

If you had 50* total on it without vacuum, then you were on your way to hurting the engine.

Having to mat the pedal when starting is also indicative of not enough initial timing.

Put a timing light on it at idle and see where it is set. Sounds like they did the total timing deal which may well be the correct total number. It should have 16-22 is my guess, but they backed out 12ish degrees. you need to get both ends of that under control.

I agree with Cracked 100%. Yes - sometimes there can be hot start issues. But in this case - given what you said they did & said - this is not enough initial. A GOOD dyno tuner would tell you what they found for the initial timing, the centrifugal timing, and the vacuum if it's connected. They would have sold you some small parts to tune the distributor (a $5 spring package),they would have charged you for labor to properly set the centrifugal, and they would have told you what everything was when they were done. I'll add- and it would have startted fine for you.