Corsa 140 running horribly

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junkyardkustoms
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Corsa 140 running horribly

Post by junkyardkustoms »

Quick question. My Corsa is running horribly and won't idle. Sometimes it doesn't want to accelerate, but will sputter and suddenly all cylinders come online and has good power. When I was trying to clean the carbs I noticed that I could spray carb cleaner down the primary on the passenger side and it nothing seemed to happen, but if I sprayed it down the primary carb on the drivers side it will bog down and die with only the smallest amount of carb cleaner. Any ideas what this means? Thanks on advance!
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cad-kid
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Re: Corsa 140 running horribly

Post by cad-kid »

If you have dual exhaust you can listen to each bank. Also you can carefully feel (or use a infrared thermometer) on the cylinder heads if the engine is the same temp on each side. You could have ignition (plugs, wires) or fuel issues.

Good luck :tu:
Jeremy (cad-kid)
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bbodie52
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Re: Corsa 140 running horribly

Post by bbodie52 »

As I attempted to point out in an earlier post, your Corvair is an unknown quantity at this point. You do not know much about its maintenance history or its current underlying condition. You only know the end result... poor, inconsistent and unreliable operation.

Having a cell phone and a membership in AAA to cover towing is useful. Always a good idea with a 50 year old car!

But seriously, there could be multiple, overlapping problems that complicate and interfere with a clear diagnosis. The symptoms are somewhat vague and unclear, and with an unknown car you should undertake a path of discovery and verification, which can help you to learn about your car as you proceed.

Assuming that the fuel system is filled with fresh, uncontaminated fuel, check the fuel pump for proper operation, with both good pressure and volume -- following the shop manual procedures.

Run a cylinder compression check to determine the condition of all six cylinders.

Perform an ignition system tune-up, replacing and adjusting ignition components, as needed. Depending on your budget, you might consider an electronic breakerless upgrade to eliminate the points and condenser. There are several options if you want to consider this approach, with a cost of about $200 if you wanted to replace or upgrade the distributor, plugs and plug wires, etc. If the condition of your current components are good, you can selectively perform a minor ignition system tune-up with just points and condenser, if the remaining ignition parts appear to check out OK.

Spraying carburetor cleaner around the outside of the carburetors and down the carburetor throats is usually ineffective if the internal fuel passages are clogged. Disassembly, chemical cleaning in carburetor parts dip, and careful re-assembly and adjustment with good rebuild kits is much-more effective.

Check all systems for vacuum leaks. Adjust and synchronize the carburetors. In the end, a good methodical tune-up will give you experience and knowledge and will establish a performance baseline and an engine that runs well and is a known quantity..
Brad Bodie
Lake Chatuge, North Carolina
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junkyardkustoms
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

I just didn't want my introduction post to get too far off topic with more emphasis on diagnosing the engine or where best to start replacing and rebuilding components.
Melb-Mike
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Re: Corsa 140 running horribly

Post by Melb-Mike »

As Brad pointed out, too many unknowns.

However, an engine that runs poorly and then runs great for a brief period eliminates motor basic health, like compression and ability to fire up the fuel delivery. I would bet you have a dirty fuel system, starting from the gas tank to the carbs. 50 year old car, you can bet the tank, lines and likely the carbs have flakes of rust and crud. Mine did. Fuel filters ? Yep, they're good but eventually you will need to pull the tank and blow out the lines. The scintered bronze fuel filters inside the original carbs did a good job of filtering but some of the crud developed inside the carb.

My advice is to pull the tank out (not a fun job) and blow out the lines all the way back to the carbs. If you don't do it now, you'll end up doing it later. Clean the tank out thoroughly, and if the tank looks pretty crappy, replace it for less than $200. Rebuild the carbs. And while you're blowing the kid's inheritance, put in an electronic ignition module. Plugs, wires and dist cap would be a good idea. When you're done, you'll have a much more reliable car. Or you can spend the same amount of money on tow trucks. Good luck.
Prior Corvair owner 30+ years ago
Just acquired 64 Spyder, 66 & 65 Corsa,
adding to 69 Corvette BB, 67 GTO,
2015 Corvette Z06,
04 996TT Porsche,
04 Caterham Super 7
just sold 87 Porsche 930 Turbo (Thank God)
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junkyardkustoms
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

I kind of thought that fuel was the culprit. I wish I didn't just fill up the tank! Where is the stock fuel filter located. I know about the ones in the carbs mentioned earlier. I don't see any other filters in line. Is there one in the tank too?
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Re: Corsa 140 running horribly

Post by davemotohead »

There is a sock on the fuel sending unit in the tank and the carb stones, that is it, the best place to add a filter is at the connection behind the drivers side rear tire.
Melb-Mike
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Re: Corsa 140 running horribly

Post by Melb-Mike »

On my 65 Corsa, prior owner had a filter installed between the fuel tank and the line going in the "tunnel". I didn't like that since it seemed a bit exposed. I installed a new filter inside the engine compartment left side just after the primary carb. Of concern with this location is if the connection fails, I will have one giant bar-B-Q with the alternator acting as the potential ignitor. I think Dave's suggestion of installing one near the left rear wheel but BEFORE the engine compartment makes more sense. However, it's a PIA location for servicing.
Prior Corvair owner 30+ years ago
Just acquired 64 Spyder, 66 & 65 Corsa,
adding to 69 Corvette BB, 67 GTO,
2015 Corvette Z06,
04 996TT Porsche,
04 Caterham Super 7
just sold 87 Porsche 930 Turbo (Thank God)
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junkyardkustoms
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

It has been over 12 years since I've dealt with a carb, now I have 4 to sort out. So please be patient with me while I try to relearn. Tonight I had her running and noticed that if I partially covered the primary carb on the left that the idle raised smoothed out. This is the same carb that sputters and dies when even the smallest amount of carb spray is shot down that barrel. So I'm a little confused, if I'm thinking about this correctly. When I richen the air/fuel ration with the carb spray, it dies. So I would think that means it's so rich that it can't handle the extra fuel. But if I partially cover the carb thus providing the same rich air/fuel ratio by decreasing the amount of air, the idle smoothes out and it stops trying to die. Please correct me if I'm thinking about this the wrong way.
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Re: Corsa 140 running horribly

Post by bbodie52 »

:dontknow: The abnormality you have noticed is only a symptom that points to a likely need for a carburetor rebuild.

Since when is carburetor spray equal to gasoline? if a low speed or idle fuel passage is partially blocked — so that the idle mixture is lean — I don't believe that spraying carburetor cleaner down the throat of the carburetor will correct the problem.

ImageImageImage :wrench: The normal way to correct a likely problem with dirty, clogged and incorrectly adjusted carburetors is to remove them and disassemble them. The metal components are soaked in carburetor parts cleaner, rinsed, and dried. A carburetor rebuild kit is applied to each clean carburetor, and it is carefully inspected, assembled, and adjusted to prepare it for re-installation. This is done with each Corvair carburetor. An insulator (spacer) and a pair of base gaskets are installed under each carburetor to ensure a proper seal. All adjustments are checked and corrected, if needed, and all vacuum lines are checked to confirm that there are no vacuum leaks. The fuel pump should be tested for proper volume and pressure. The idle speed and mixture screws are synchronized and adjusted for proper idle, and the throttle linkage is adjusted to ensure that both primary carburetors are synchronized and are delivering equal airflow as the throttle is opened. (A uni-syn gauge is useful at this stage. It helps to ensure equal, matched airflow through each primary carburetor at both idle and at open throttle positions).

:link: http://www.corvair.com/user-cgi/catalog ... ow_page=57
Image

The attached manuals and guides can help you to learn the Corvair carburetor functions and theory, and the procedures for removal, overhaul, re-installation, and adjustment of the carburetors. The procedures are methodical, but not difficult or overly complex. As you work through the process you will come to understand the fuel system, and how the components interact.

Don't be overwhelmed by the documentation. There is some overlap between the documents and manuals, but sometimes an alternate explanation or an extra picture or illustration will help to clarify things.

If you have questions or need some clarification concerning some aspect of the material in the manuals and publications, just come back to the Corvair Forum and ask your questions. Browse through the carburetor pages of the Clark's Corvair Parts online catalog too. There are tips and comments embedded in the catalog that can be useful, and seeing the components and parts that are offered can give you ideas regarding the process on your Corvair. Corvairs often respond surprisingly well to a careful carburetor overhaul and adjustment process. Coupled with an ignition system tune-up the results can be very rewarding as you drive your Corvair, and the successful completion of the tuning process can be a great confidence builder as you continue to learn to maintain your Corvair.
Attachments
DELCO ROCHESTER - Models H, HV Carburetor Service Manual.pdf
DELCO ROCHESTER - Models H, HV Carburetor Service Manual
(1.79 MiB) Downloaded 24 times
Corvair H and HV Carburetor Rebuild Sheet.pdf
Corvair H and HV Carburetor Rebuild Sheet
(1.67 MiB) Downloaded 24 times
1965 Corvair Chassis Shop Manual - SECTION 6M - ENGINE FUEL.pdf
1965 Corvair Chassis Shop Manual - SECTION 6M - ENGINE FUEL
(8.87 MiB) Downloaded 20 times
1965 Corvair Chassis Shop Manual - SECTION 6 - ENGINE TUNE-UP.pdf
1965 Corvair Chassis Shop Manual - SECTION 6 - ENGINE TUNE-UP
(2.92 MiB) Downloaded 22 times
1965 Corvair Assembly Manual - CARBURETOR & FUEL SYSTEM.pdf
1965 Corvair Assembly Manual - CARBURETOR & FUEL SYSTEM
(3.92 MiB) Downloaded 30 times
Brad Bodie
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junkyardkustoms
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

Well I was looking around and noticed the plastic choke tripper was broken on the problematic carb. So I fixed it and it seems to idle a bit better now, but still not 100%. My battery is swollen and keeps dyeing do I'm about to replace it. But I did notice something. In other cars, I've tested the alternator by removing the battery while the engine is running. If it keeps running, then the alternator is doing it's job. I tried that with the Corsa and it immediately started to sputter worse and died about 30 seconds later. So is it safe to assume that the alternator isn't quite up to doing the job anymore?
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

I have a question about spark plugs. I've read so many posts about plugs that I'm all twisted and confused now. I've never seen so many posts about what plugs are safe to run. Too hot, too cold, compatible with upgraded ignition systems, extended electrodes burning holes in pistons... it's getting crazy. I would just like a straight answer. 140 with stock ignition, nothing fancy. NGK BR6HS? AUTOLITE 2656?
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cad-kid
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Re: Corsa 140 running horribly

Post by cad-kid »

junkyardkustoms wrote:I have a question about spark plugs. "snip" I would just like a straight answer. "snip"
I understand your frustration. Everyone seems to have an idea with plugs on what works best. Just don't ask about what oil to use (its worse!) :rolling:
Jeremy (cad-kid)
Kronenwetter, WI (Central Wisconsin)
SOLD 9-2016 65 Monza 4spd/140
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junkyardkustoms
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

I feel stupid asking such a silly question, but there truly is far more information than what I can make heads or tales of. But apparently I shouldn't just go down to O'Rielys and get whatever they have.
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davemotohead
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Re: Corsa 140 running horribly

Post by davemotohead »

NGK B5HS or cooler B6HS , put a little anti seize on the threads.
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junkyardkustoms
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Re: Corsa 140 running horribly

Post by junkyardkustoms »

THANK YOU! That's all I was trying to find. I'll see what (if any) difference new plugs makes.
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