Spark, Fuel - no start....HELP OUT OF IDEAS

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Gearjamr
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Spark, Fuel - no start....HELP OUT OF IDEAS

Post by Gearjamr »

So this is my first time posting on this site. I tend to be stubborn when needing help but, I am at my wits end. I have owned my 65 Monza 110 for about a year and a half. This is by far one of my favorite classic cars that I own. The previous owner claimed to be a car lover and a garage hobbyist and I have found that he was a bit of an idiot. Aside from the history here is the issue at hand....vehicle stalled out going down the road. I was able to get it going and got it home. The poor thing was obviously having issues with fuel delivery so I decided it was time to rebuild the carbs. Order the parts kit from clarks and went to work. During the carb rebuild I noticed the float springs were missing. I once got new ones from clarks and installed them accordingly.
I also decided while I was at it I would drop the engine and clean things out, change seals, fluid etc. Got it all back together and things seem decent enough. For a little while I started to have a problem with spark. Traced the problem and found that the coil had gone bad. I decided that while I was at it I would replace the coil, cap, rotor and points. Set the points according the shop manual at .19 per the gauge. Locked it all down and verified spark both from the coil and via observing manual cap separation etc. Verified proper install of the fuel pump and all associated lines. During the engine refresh I decided to change them. I have good fuel delivery and pressure to both carbs equally. I also double checked all vacuum line connections and the overall setup. Managed to get the vehicle to fire and run well for a bit. After starting a couple of times I shut it down and was working on engine clean up based on the services performed. Tried to restart and nothing. Vehicle was behaving as if it wasn't get spark or fuel. Vehicle was showing signs of difficulty with cold start but, I noticed it would start with the help of a start assist from a battery charger. So I decided to replace the battery as well and upgraded to a 700 CCA battery. Tried to start again....still no joy.
A couple days later I pulled the number one plug after reading several entries on this site and found the TDC. Marks lined up great and I reset the distributor to match. Tried to start and she fired right up again. This time sounding better than before. I figured I was on the right track and all should be well. I decided to once again start, run, and restart a couple of times to see if the issues with starting had been resolved. Once again after a couple of iterations it failed to start again. Checked the plugs and they look good, no fouling etc. Open the choke and throttle plates on the carb and observed fuel vapor that looks like a mist swirling around inside. Blew it out and noticed that the intake had fuel moisture present on the bottom of the manifold. Not a lot...but, noticeable.

Here is what I have done this far:
1. Rebuilt carbs (adding springs) and reinstalled.
2. Replaced fuel lines
3. Replaced Cap, rotor, points, spark plugs, coil and battery.
4. Changed all fluids
5. verified proper belt and tension
6. Found TDC for cylinder 1, adjusted distributor to match etc.

I am at a complete loss for what it could be. Any ideas would be appreciated. I have talked with my local New England Corvair club and one thought is vapor lock, another is that the fuel lines I am using are low grade and causing issues. I have even considered the possibility of over pressure from the mechanical fuel pump.

Please keep in mind that the vehicle was running prior to the carbs becoming clogged. I have not adjusted any valves, or mixtures on the carbs etc. I have ensured proper seating of the fuel pump and so on. I have also verified that the carb floats are behaving as they should and sitting atop the fuel levels rather than submerged. I have also verified that the fuel stop on the floats is also good and clear and not binding. Float settings were measuring at about 1.25 inches from the base of the float to top of the carb.

plrgpr
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by plrgpr »

I know this is a shot in the dark, but check for a pin hole leak in the fuel line starting at the fuel tank especially where it passes through a bulkhead etc. Years and years ago, I had a 65 140 hp for a daily driver that was behaving just as you describe yours. I found a rubber grommet had worn through and the fuel line rubbed against the metal and caused a pin hole so small there was no drip, just some dampness, but evidently enough to suck some air and create something like vapor lock. Replaced the line and no more problem.
Gary Roberson
66 Vert 140 4-sp Corsa “clone”

Gearjamr
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by Gearjamr »

I will prop it up tomorrow and inspect the bulk head area. I did move the inline fuel filter from the engine bay to the otherside so the pitch of the filter was more vertical hoping it would limit air ingestion. Maybe some air is getting throught there.

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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by terribleted »

Change the condenser in the distributor. Sounds like it may be bad. It starts gets hot and then stops working....cools off and then works again. Cheap simple to change...give it a shot.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
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Gearjamr
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by Gearjamr »

My apologies....I forgot to mention that it was changed when the points were.

joelsplace
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by joelsplace »

You need to determine if it is fuel or spark. If it is spark you are probably looking at the condenser or coil.
Fuel - you may have a combination of issues. How much fuel pressure? The rubber lines can collapse and cause it to run out of fuel. They open up and fill the line, the pump fills the carbs and sucks the line closed again. Reach under the passenger side and squeeze the rubber line. If it feel spongy it is bad for sure.
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bbodie52
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by bbodie52 »

In reading your description, I saw a lot of general observations, some assumptions, but little in the way of actual instrument measurement. For example... to check for the possibility of fuel starvation, did you actually measure fuel pump pressure AND volume? It is easy to have a pump that delivers correct pressure, but cannot produce adequate fuel volume. A feed line leak or cracked/damaged/loose rubber hose between the tank and the pump can create an air leak that will keep the pump from being able to create a solid vacuum to pull a good supply of fuel from the tank. Without adequate fuel supply, the pump can generate adequate fuel pressure to the carburetors, but only until it is starved for gasoline from the tank. The pump must also be installed to the proper depth and anchored properly using the tapered bolt that is screwed into the tapered hole on the side of the pump.
bbodie52 wrote:The pump push rod is driven by a cam lobe on the crankshaft. The repeated "upstroke" causes the pump to form a vacuum in the feed line from the fuel source (tank or gas can). As the fuel is drawn into the pump chamber, the one-way valve in the pump inlet closes at the top of the stroke, and the spring in the pump forces the diaphragm back down to push the fuel out of the pump through the other one-way valve, toward the carburetors. The spring tension determines the fuel pump outlet pressure.

Check to make sure you are fully inserting the pump so that the pushrod driving the pump gets a full stroke to drive the fuel pump. Proper installation of the new parts is critical,,,
To remove and reinstall the fuel pump, be sure that you have installed it properly. It is important to ensure that the fuel pump is correctly seated and installed. There is a hole in the side of the pump shaft that the tapered bolt tip must seat into. If the pump is sitting too high and the bolt is simply pressing against the side of the pump housing, rather than seating inside the tapered hole, the pump push rod will not be doing its job. Fig. 57 in the shop manual page shows the tapered hole that the tip of the bolt fits into. This ensures proper installation and seating of the pump.

Image

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Also...
There are two relatively simple tests outlined in the Corvair shop manual. These tests measure output pressure and fuel delivery volume. The output pressure test utilizes a common vacuum/pressure gauge that is relatively inexpensive. The output pressure is regulated by an internal spring that is contained in the upper pump housing. Unless your pump springs a leak in one of the diaphragms or seals, it is likely that the output pressure will not change with age. However, new pumps may be fitted with a spring that produces an output pressure well in excess of the 4-5 psi standard. High-pressure can cause carburetor flooding, and is particularly a problem with the Carter YH carburetor found on turbocharged Corvairs, which is sensitive to excessive fuel pressure.

A new fuel pump should always be tested for output pressure. If the pressure is found to be excessive it may be possible to cut the spring or to exchange the spring from the old pump and fit it into the new pump. This may correct the output pressure.

The second test measures fuel flow at the fuel pump outlet. The standard in the shop manual states that the pump should be able to deliver 1 pint of fuel over a period of 40 seconds or less at engine cranking speed. If your pump does not appear to have any leaks and can pass the output pressure test, but fails to deliver the needed fuel volume, the problem may not be with the pump itself. There is a long fuel line that runs the length of the car from the fuel tank to the fuel pump. In order to pressurize and deliver fuel to the carburetors, the pump must be able to create a continuous vacuum in that fuel line to draw the fuel from the tank to the pump. Most of the fuel line is made up of steel tubing and is unlikely to develop a leak. However, there are two short lengths of rubber fuel hose in the fuel path. One section of hose is found at the fuel tank outlet, while the other is found adjacent to the starter motor — just before the line enters the engine compartment. The purpose of the second hose is to absorb vibration from the engine and prevent it from reaching the rigid steel fuel line. If either one of these two hoses develops a leak, the leak itself may not be apparent because the line is not under pressure so fuel will not be forced out. Instead, the leak amounts to a vacuum leak, which can allow air to enter the fuel line. This can prevent fuel from being drawn from the tank to the fuel pump, much like you might experience with a drinking straw if the straw was to split and developed an air leak in the side of the straw. What appears to be a faulty pump that is causing fuel starvation problems in the carburetors often turns out to be a leak in the fuel line at some point between the gas tank and the fuel pump. So if fuel starvation becomes a problem with your carburetors, there is a tendency to question the condition of the needle and seat valve inside the carburetor, or to blame the fuel filter at the carburetor inlet (thinking it is clogged), or to blame the fuel pump itself. Before you blame the pump and toss it, or abandon it and replace it with electric fuel pump, be sure to check the condition of the rubber fuel hoses at each end of the long fuel line between the fuel tank and the fuel pump. You may find that a couple of hose clamps and a few inches of replacement fuel hose is all that necessary to get you back on the road!
:doh:

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For a quick check on fuel availability in the carburetors, you can peer down the throat of each carburetor while holding the choke open. Open the throttle quickly. You should see a squirt of fuel injected into the carburetor throat from the accelerator pump. This confirms the presence of fuel in each float bowl.

With the air cleaner assembly removed, when holding the choke open and peering down the throat of each carburetor, do you see a squirt of fuel from the accelerator pump in each carburetor when you open the throttle rapidly? If the jet of fuel is not observed, the float bowls may be dry, possibly due to stuck needle and seat assemblies blocking the fuel inlet.

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Also, has the compression been tested/measured at each cylinder? Has the point dwell been measured using a dwell/tachometer? Then has the timing been checked with a timing light? When you assumed a bad battery, did you measure the battery voltage and the voltage present when the charging system was operating? An alternator should put out between 13.5 and 15 volts of power. Fully charged automotive batteries should measure at 12.6 volts or above. When the engine is running, this measurement should be 13.7 to 14.7 volts. A properly functioning voltage regulator in the charging system limits the maximum voltage. If the voltage regulator is malfunctioning, the system voltage can increase beyond these limits as engine speed increases.

Do you have a multimeter to measure the system voltage? Have you measured the battery voltage with the engine off, the voltage present with the engine running at idle, and the voltage as engine RPM is increased?

Image
Brad Bodie
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Image 1966 Corvair Corsa Convertible

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terribleted
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by terribleted »

Gearjamr wrote:
Fri Jul 26, 2019 7:46 pm
My apologies....I forgot to mention that it was changed when the points were.
I would change it again just in case:) I have had new bad one 2 times recently.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

64powerglide
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by 64powerglide »

Did you put a timing light on it & check the timing running? You need to be at 12 to 16 BTDC. :my02:
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Gearjamr
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by Gearjamr »

Ok....so to answer some of the questions about determining what was good or bad electrically. Yes, i used instruments to determine voltage and ohm impedance before dismissing ant part as bad. In terms of whether or not i installed the fuel pump correctly the answer again is yes, and it is less than a year old. I appreciate the copy and pasting from other posts. But I dont have a turbo. Nor do I have YH carbs. So most of that was useless. The only measurements I have not done with an appropriate gauge is fuel line and vacuum pressure tests. I have not done a compression test on the cylinders as the vehicle was running previously. With regards to the timing light....it was actually my next step before she went into her I am not starting status. So once again I propped the different carbs flaps open and hopefully it will start today.

Gearjamr
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by Gearjamr »

Oh....forgot to mention. Yes, I checked the carbs for squirting etc. In lieu of a pressure meter on the fuel line (dont have one yet) I disconnected the fuel lines at the carbs and held a clear 20oz bottle to the fuel line. While doing this my buddy turned the ignition enough for to observe substantial fuel flow.

64powerglide
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by 64powerglide »

Float level should be close to 1 & 3/4 inches.
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by terribleted »

64powerglide wrote:
Sat Jul 27, 2019 5:18 am
Float level should be close to 1 & 3/4 inches.
This is a good thought could be a rich or flooding condition, but, I think you mistyped 64powerglide float level should be 1 13/64" which is just under 1 1/4". Are the plugs black and fouled at this point after multiple tries to start they may be? Is there any fuel dripping in the carb immediately after cranking as the needle seats allow system fuel pressure past (they should not do this and if there is dripping then flooding may be an issue)? Another thought, try replacing the point lead from coil to points perhaps there is a break in the wire which would cause an intermittent issue. Any suitable gauge wire will work for troubleshooting:)
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
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64powerglide
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by 64powerglide »

Ted, I should have said float drop. Sounds like his is flooding out. Then the plugs get wet & won't fire. After a while the plugs dry out & it starts but when it's off for a short time it won't start again. Ask me how I know this happens. ::-): Click the attacnment to enlarge.
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64Powerglide, Jeff Phillips

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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by terribleted »

64powerglide wrote:
Sat Jul 27, 2019 12:25 pm
Ted, I should have said float drop. Sounds like his is flooding out. Then the plugs get wet & won't fire. After a while the plugs dry out & it starts but when it's off for a short time it won't start again. Ask me how I know this happens. ::-)
Flooding could be his issue indeed. The chart you posted above is WAY off the shop manual in float level spec however (it may be just the difference in method of measuring however as it measures to the flat of the float body not the top of the flange). The spec shown in the carb section that outlines rebuild and adjustments states 1 13/64" which is like 1.20 to the highest point of the float (the flange) . This chart says 1 1/16 which is like 1.06. I have found that I commonly have issues with flooding if the float level is set at even 1 1/8" which is 1.12. I always set 1 7/32 (1.21) or just a hair more than the manual spec in the carb section and virtually never have an issue with flooding and have never seen a starvation issue either. There is a chart in the specs in the back of the 65 manual that say this measurement should be 1 1/8. I have seen many folks have flooding at 1 1/8. There is a whole lot of discrepancy between different sources...LOL including different places in the same shop manual:0
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

64powerglide
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Re: Spark, Fuel - no start....HELP OUT OF IDEAS

Post by 64powerglide »

Ted, my right carb kept leaking so I set the float level at 1 & 3/8 & have the float drop at 1 & 3/4 & haven't had a problem since. Before I did that I would start it & right away knew it was running on 3 cylinders. Once I got out & walked to the back of the car & the right tail pipe was spraying gas all over my Taurus. :eek:
64Powerglide, Jeff Phillips

Kalamazoo, Mi..

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