Cant keep my mccollough airstreamIV running please help!!!!!!

Take it to a mechanic

Idle air control valve
ignition coils
spark plugs
Is the check engine light on?
If so get it checked.

If it still has a good spark it must be a fuel issue, replace the filter in the fuel tank check the fuel hose up to the carb for cracks or splits, if this does not help the next step is to service the carb, let me know if you need help with this.

There is a big possibility that there is a fault in the cdi unit or it is to do with engine firing. So basically something wrong to do with electricity from magneto up to the spark plug. It is quite a difficult thing to spot as there is no ECU like new vehicles which can tell you more exactly where the fault is. It is more to do in terms of trial and error, like changing parts and test until you find the cause of the problem. A good idea is to find another bike of the like to like model and swap parts around and test. Hope this helps and good luck with this.

check the idle control sensor

Here is a pic of a schrader valve. They all look about the same.
If there isn't much pressure, cycle the ignition without turning the engine over and try again. If it is still weak, you may need a new fuel filter. If it is strong, you may have dirty or clogged fuel injectors.

It may be spark, but I'm inclined to think it is fuel related.

Good luck, and keep us in the loop!
JT

Hi and welcome to FixYa,

Appreciate the direct "Ask Me".

Your described problem based on the bike being a 1982 model could be varied, among them are:

• weak spark - not necessarily weak battery. Culprits could be loose loose connector to the CDI, low IGN +12 to the + terminal of the coil (check with a voltmeter while just switch on and when cranking/starting), or even a loose ground terminal. Check spark by removing plugs, reconnect the plugwires, let the threaded end touch metal part of engine, crank. Sparks should be strong;
• corroded/poor contacts in the ignition switch resulting to the above. You can test by running a jumper wire straight from the battery to the + terminals of the ignition coil;
• too lean air/fuel - plugs should be brownish in color;
• air or vacuum leak - resulting to the above and high or poor idling;
• unbalanced carbs - carb check/clean, verify air adjustment screw number of turns,
  
• compression low - have a compression check.

Would look forward to your updates. Good luck and thank you for using FixYa.

amiseybold;

First check for spark. Remove the spark plug. Leave the spark wire connected. Hold the plug against the metal of the mower engine so you have a ground and can see the gap of the electrode where the spark jumps across. Have someone pull the starter cord and verify that you have a spark. Hold it by the threads of the plug so you don't get a little spark jolt yourself.

go to an auto parts store and get a can of starter spray (it's actually ether), Remove the lawnmower spark plug and spray a little ether in the plug hole. Put the plug back and tighten it and see if it starts.
It will probably start, run for 5 or 10 seconds and then die. Repeat this procedure once or twice again and eventually it will start to draw gas from the lawnmower tank.

A seasonal tip. when you put the mower up for the winter, **** the remaining gas out of the tank, start the engine and let it run until it uses up the gas in the carburetor. This will make iot much easier to start in the spring

Hope this helps Good Luck Loringh PS Please give me a rating

check your fuel pressure and also check your plug gaps and make sure you have a stong spark, you say it stays running once started on ether? does it run well or poorly? is it drivable or not please explain in more detail -please rate -jeff

Need to get a scan tool and look at the data stream while it is running for alot more info.Also any trouble codes.Sounds like initially,the engine isn't getting any fuel.I would have a pressure gauge connected to the fuel rail on the engine,so i could monitor the fuel pressure while all this is going on.Items to look at on the data stream would be timing,what timing is the PCM commanding for the engine.Also,have you checked for continuos power feed to the coils during this no start condition,and fire at the plugs while cranking.You could possibly still have spark,but maybe it is extremely weak?I have seen bad ignition switches cause weird problems before too.Many things power up through the ignition switch,just a thought.Have also seen bad PCM's cause strange problems..38 volts is a little on the low side for GM.Usually see those at,at least .50 and up,and rise steadily while pressing the throttle,up to just under 5.0 volts.Potentiometer with 5 volt supply.Vacuum leak can be checked with engine running at a steady idle speed,spray brake cleaner all around the intake manifold and listen for engine speed change.