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starting problem, including clues
Posted by: hootsk ()
Date: December 26, 2017 04:05PM

Hey, all. I try not to clog this forum with questions and figure out problems on my own, but this time I'm at the edge of my diagnostic experience.

I have a '62 Greenbrier with a 4-speed and a '65 110: rebuilt Clark's 110 carbs and a Pertronix Ignitor II kit in a rebuilt 1110319 distributor. There's a strong blue spark at all six plugs, and once it starts, the engine sounds good. You can hear it run here:

Video from behind:
[vimeo.com]

From the tach:
[vimeo.com]

The problem is, it takes 5-10 minutes to start. Every time. Even if it's warmed up. When the key is first turned, the engine turns over without firing for a couple of minutes at least. After a while it begins to fire, but won't catch. After another while, firing becomes more and more rapid until the engine finally catches.

Clue 1? After a couple of minutes of cranking, the engine fires if you keep your foot *off* the pedal.

Clue 2? Warmed up or cold seems to make no difference.

Clue 3? The engine will idle forever, but if you put it into first and step on the gas, unless you keep giving it gas, after a moment it may lose power and sometimes stalls.

Clue 4? Though it sounds even when it idles, very occasionally, it will backfire.

Clue 5? Before it starts, the left side smokes and the right doesn't. When it backfires the backfiring comes from the left side, not the right.

What should I check?

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Re: starting problem, including clues
Posted by: irfgt ()
Date: December 26, 2017 04:13PM

I would first put points back in and see what happens.

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Re: starting problem, including clues
Date: December 26, 2017 04:19PM

Since you say you are getting good spark at the plugs, Sounds like fuel problems.
What happens if you put a couple teaspoons of gas down each carb throat, the crank on it?
Check that you have a good flow of clean gas thru to the carbs. Remove the inlet pipe and put a metal cup to catch the gas. Have someone crank the engine and see if you have a good flow, not a dribble.
Pull each of the large nuts off the carburetor inlets and check the small filters inside there.
Backfire is usually from a lean fuel condition.


Dan Davis ~ Pierce County, WA ~ CORSA Western Director + Corvairs NW + North Cascades Corvairs + Corvanatics
1966 Corsa Turbo coupe ~ ~ 1966 140 Corsa ~ ~ 1965 Monza 140/4 'Vert Sierra Tan/Fawn ~ 1964 Monza 'Vert (SOLD) ~ 1960 Monza Ermine White/Red PG ++ ~ 1965 Monza 140/4 Evening Orchid w/ ivory/black interior ~ 1962 Monza Wagon 102/4 ~ 1963 Rampside/Scamper ~ 1963 Red/Greenbrier ~ 1969 Ultra Van #468



Edited 1 time(s). Last edit at 12/26/2017 04:21PM by 1966-Corsa-GT-180.

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Re: starting problem, including clues
Posted by: Chilly Willy ()
Date: December 26, 2017 04:46PM

If you haven’t already, do a compression check.
It does sound like a fuel issue. Verify The accelerator pumps are squirting. Double check for vacuum leaks.are the carbs adjusted correctly?
Also verify ignition Timing.




The Corvair, Keeping Nader Notorious winking smiley


Will
Northern California

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Re: starting problem, including clues
Posted by: ken ()
Date: December 26, 2017 05:23PM

Sounds like low fuel pressure .

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Re: starting problem, including clues
Posted by: SoloCP ()
Date: December 26, 2017 05:56PM

Let's start at basics, Get rid of the Petronix for now. Install a new set of points and condensor. Use a dwell meter to set the points. Check the cap for any evidence of arching. Now check for consistent fuel delivery at the carbs, remove the lines and install catch bottles have done one crank or use a remote starter. Take the coil wire off both cap and rotor before you do above. Once you determine that you have fuel and spark, check to make sure the accelator pumps are squirting, just move throttle linkage and look down the throats you should see to streams of fuel. Now you know that you are getting fuel and spark loosen the distributor enough so you can move the distributor by hand but not so loose it moves on it own. Now with someone cranking or using a remote starter turn the distributor slightly while cranking the engine you should be able to get it to start. Once running set the timing. I just went thru all this above on a 63. The only difference is I had clog fuel filters caused by rust in the fuel tank. (Check your fuel filters at the carbs) But had the same problems with it running and backfiring. Good luck.

Don
AKA (Polyvairist)
Kansas City
HACOA
Broken Halo Corvair Garage.
61 Lakewood
62 Monza aka (Flicka)
62 Rampside
63 700 Sedan 3 Speed
64 Spyder Coupe (Bill Pierson Car)
64 Monza Convertible,140/4 Speed,Electric Heat,Kelsey Hayes Wheels
64 Spyder Blown, (Dave Bolduc Car)
65 Corsa 3.1 Liter Triple Weber (aka Unsafe)
66 Corvair V8 SuperVair (Created by Archibald Evans)
66 Avenger, Corvair Turbo, Fuel Injected, Air to Water intercool 140. (Michael Mann Car)

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Re: starting problem, including clues
Posted by: MattNall ()
Date: December 26, 2017 10:55PM

Left side smoke = WHITE?? Raw gas! carb is flooding.....IF choke is working!!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: starting problem, including clues
Posted by: red monza ()
Date: December 27, 2017 07:02AM

Pour about a level teaspoon of gas down the carbs...if it starts good...fuel is your problem.

If it does not start fairly well...your problem more than likely is electronic.

Most conversions to electronic need a full 12 volts to the distributor..that is my guess as to why it is hard starting...check the voltage on the neg (-) side of the coil to the distributor.Check the requirements for your points conversion.



Edited 1 time(s). Last edit at 12/27/2017 07:03AM by red monza.

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Re: starting problem, including clues
Posted by: Chasgee ()
Date: December 27, 2017 08:43AM

My car did this after I rebuilt the carbs. Turned out to be the float level. It was too high and causing flooding.

Chuck Gee
Carlsbad, CA

1963 Monza 102 - in the family from new
1966 Corsa 140 Coupe - new project

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Re: starting problem, including clues
Posted by: Seth Emerson ()
Date: December 27, 2017 09:41AM

Try the fuel down the carb throat as step one. You have Dual exhaust? Only way to isolate L/R carbs. If you do, swap the left/right carbs and see if the white smoke out the exhaust moves with the carb. Lot's of other good advice above.

Seth Emerson

Check my new Performance Corvair Web site [www.perfvair.com]

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Re: starting problem, including clues
Posted by: hootsk ()
Date: December 27, 2017 11:10AM

Great advice, thanks all.

The good news is there is a little more than 12V at the coil. It also warms up to 180F quickly and stays there, and oil pressure is a consistent 25 psi at idle. Timing was about 4° BTDC and I moved it to 12° BTDC after reading some other threads and it doesn't seem as gutless now. (This is a '65 110 bolted to a 4-speed.)

The bad news is there may be more than one problem. First the flow from the fuel pump looks weak. Then the accelerator pump doesn't look like it's working in either carb. Pulling the throttle doesn't squirt any gas in either.

What approx. psi should fuel pressure be between the pump and carbs? Have any of you put a Schrader valve on your metal lines as a test port?

Chuck Robertson

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Re: starting problem, including clues
Posted by: Richard ()
Date: December 27, 2017 11:21AM

Back up about three steps. Your video above shows the Spyder tach indicating 11-1200 rpm. That's not a idle rpm. You need to adjust the idle down to about 600 rpm before you check base timing or make adjustments.

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Re: starting problem, including clues
Posted by: MattNall ()
Date: December 27, 2017 11:26AM

3-4 psi.... just .after you get the engine warmed up........shut off.... remove line from on end of carb and put gauge on that line.... restart and see what you have..

I have a test rig that goes inline with one of the carbs.





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: starting problem, including clues
Posted by: MattNall ()
Date: December 27, 2017 11:35AM

Also, to test carbs;

Get a plastic squeeze bottle and fill each carb with gas thru the VENT....do not worry about flooding..

Now actuate the crossbar to open throttles rapidly and see if you have TWO squirts in each carb.





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: starting problem, including clues
Posted by: hootsk ()
Date: December 27, 2017 11:52AM

Initially I had some trouble getting it to idle below 1100 rpm, when that video was made. But I kept adjusting the carbs using an Edelbrock 4025 Uni-Syn until it was closer to 700. (Haven't quite achieved 600 yet.)

I got the 4° BTDC setting out of the '65 book, but it seemed to lack power so I wasn't going to leave it there. 12° BTDC seems stronger overall and it's more even at 700 rpm.

But no accel pumps makes me think the carbs are going back to Clark's. Maybe punctured diaphragms from sitting too long? Probably my fault. Probably punctured diaphragm on the fuel pump too?

MattNall: nice rig. I was thinking, I have a test kit for EFI with a wide-band gauge that goes down to 0, but the hose has a Schrader coupling on it.

This is already better. Thanks all.

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Re: starting problem, including clues
Posted by: MattNall ()
Date: December 27, 2017 12:09PM

Rochester HV's have CUPS... no diaphragm.... if carbs are rebuilt from Clark's Corvair Parts they are most likely fine..

Are you still in the Seattle area? several CORSA chapters in your area... many members are here! Ask for LOCAL help....someone may be close by!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: starting problem, including clues
Posted by: hootsk ()
Date: December 27, 2017 12:32PM

The van is in Bellingham, Wash. and I have to leave for a while, but I'll be back soon. I live in New York.

Why would *both* accel pumps stop working? Clogged?

Chuck Robertson

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Re: starting problem, including clues
Posted by: MattNall ()
Date: December 27, 2017 01:07PM

Those TWO little holes in the pic get clogged... 0.026"

How old are these carbs since rebuild? Sounds like they set for periods with gasoline in them?





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: starting problem, including clues
Date: December 27, 2017 01:14PM

You may have fuel delivery issues from the tank, sender/pipe, hose connections, etc.
Any point along the fuel line from inside the tank to the pump could cause an air leak or a restricted line. Both will result in low fuel delivery past the pump.

Try blowing back on the fuel line while someone listens at the filler with the cap off. Should hear the air bubbles. That may also knock some of the usual sediment from the "sock" attached to the inlet tube of the sender.
Make sure all the interconnecting rubber hoses are not split/hard/loose. Any air leak will pull air into the pipe and cause poor draw at the pump...

Is yours an upgrade aftermarket 12V. ignition coil? Corvair standard coils are meant to run at around 6 volts by way of the resistor wire inside the engine bay wiring harness. There is also a second wire that puts 12V on the coil during "start" only to counter the heavy draw of the starter motor and provide a hotter spark only during that short time.
The Igniter II likes 12V, but not the standard Corvair coil.


Dan Davis ~ Pierce County, WA ~ CORSA Western Director + Corvairs NW + North Cascades Corvairs + Corvanatics
1966 Corsa Turbo coupe ~ ~ 1966 140 Corsa ~ ~ 1965 Monza 140/4 'Vert Sierra Tan/Fawn ~ 1964 Monza 'Vert (SOLD) ~ 1960 Monza Ermine White/Red PG ++ ~ 1965 Monza 140/4 Evening Orchid w/ ivory/black interior ~ 1962 Monza Wagon 102/4 ~ 1963 Rampside/Scamper ~ 1963 Red/Greenbrier ~ 1969 Ultra Van #468



Edited 1 time(s). Last edit at 12/27/2017 01:17PM by 1966-Corsa-GT-180.

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Re: starting problem, including clues
Posted by: joelsplace ()
Date: December 27, 2017 01:50PM

All correct but just so he knows - the unloaded voltage will at the coil will still read 12v since the voltage drop across a resistor only happens when current is flowing.
If the points are open it will read battery voltage. Points closed should read a lower voltage if the resistor is in place.

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