1979 20 hp chrysler won't start

Jb4507hd

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Motor will not start. Model # 202h9k. Changed plugs. Rebuilt carb. Cleaned points. Checked fuel pump. Gas getting to it. Not sure what else to do. It was running a few days ago and now won't fire.
 

Frank Acampora

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Check that points wiring is correct. Check that the stop wires to the points are not shorted. This is the paired wire than looks like lamp cord. check condenser wires are nor rubbing on flywheel and shorting. If the engine has a man overboard stop switch, is the lanyard still attached?

You did torque the flywheel nut, didn't you? If not, check that the crankshaft key has not broken allowing the cam to change timing. If you removed the cam did you replace it correct side up?
 

Jb4507hd

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I will check wiring. I didn't remove cam but didn't torque flywheel nut either. It wasn't super tight to begin with. I just tightned it with a wrench. What is torque value and how do I check and adjust timing?
 

tommarvin

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Get a spark checker and make sure you are getting spark, I'm new don't have a clue about 1979 20hp. We have a 125hp it's test coil if you have a coil. Test trigger if you have it, test stator if you have it, make sure all connections are clean and tight.

You said it was running a few day ago,was this before you did all the work on the motor? If your positive you have gas, its spark, put your glasses on take the cover off and tug and twist every wire ,connector, check every inch of wire. Inside of motor is fine, something outside the motor is broken , find it.

I would get new points, condenser, rotor? that part that spins and touch the cap contacts and any other cheap ignition parts I can't think of, clean the contacts on the cap,and any other parts in the distributer.
Please tell us what it was so I can learn something.
 
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Frank Acampora

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I don't remember off the top of my head the flywheel nut torque specification and my Manuals are out in the cold. Maybe Nordin can answer you or you can go to the library and look it up in Clymers or Intertech.

In fact, I assumed that your 20 was a magneto ignition engine. If it is battery and points ignition the wiring is different so let me know. (Both magneto and battery ignition have points. The difference is battery ignition has two coils on the side of the engine and a charging stator under the flywheel while the magneto coils are under the flywheel)
 
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Nordin

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The 1979 20Hp was a downrated 25Hp, developed in 1973 in a engine family 25, 30 and 35Hp (the 35Hp came 1976). It was the first year (1979) when it became 20Hp. In 1978 it was 25Hp.

As jb4507hd want to convert to electric start I think it must have magneto ignition because the alternative was magneto with manual start or magnapower with electric start.


Flywheel nut should be torque 55-65 ft.-lb.

jb4507hd ......check and clean the points, regap to 020 and check the stop circuit as Frank suggested for grounding. It is black or brown wires looking like lamp cord they are connected to the points and short out the points to each other with the stopbutton.
Also check the stopbutton, the terminals at the button should be infinitve when not depressed.
 
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Jb4507hd

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Thanks guys. It does have magneto ignition. The terminal on kill switch are rusty. I will clean them. How do I gap the points?
 

tommarvin

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I just learned what a magneto ignition is, now that I know what a magneto ignition is, we have a battery ignition on our motor.
I would replace the magneto coils under the flywheel, unless Frank or Nordin know how to test them, I don't have a clue.

I think you test points with a feeler gauge? It's hand held with swing out pivoting metal blades of different thickness's, you find a place in the fan deck that equals .020, there might be one metal blade that's .020, or combine two or three to get to .020.
 

Frank Acampora

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Most Chrysler points are held down with two small screws. Set the rubbing block to the high point on the cam or the mark if there is one. Loosen the two screws and let the points snap closed. Clean the points and insert a feeler gauge a bit larger than .020--how much larger depends upon the spring tension and how much they will close. Tighten the mounting screws and slide out the feeler. NOW check that the gap is indeed .020 If not do it again. Then go to the other set of points.

Be accurate with your gap. The single cam operates both points. A difference in point gap can make a larger difference between the timing of both cylinders
 

Frank Acampora

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I forgot to state: When checking the point gap, if correct, the feeler gauge will slide in without forcing and should slide out with a little drag.
 

flyingscott

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Here is another way to do points which I think is easier for firs timers. Buy the biggest set of feeler gauges you can make sure it has a .019 and a .021. When you set the points the .019 will slide right through and the .021 will catch and push them apart that is .020. It's called the go no go method .
 

Jb4507hd

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I checked all wires they are good. I don't have feeler gage but points are off. I can see a gap probably an1/8 of an inch on one and no gap on the other.
I am getting fuel to plugs so it's not getting spark.
 

tommarvin

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I think the points alternate, one opens and the other closes so that's correct, I think you test points when one point is full open turn flywheel to open and close to test with feeler gauge.

Your not screwed on the broken flywheel key, spray penetrating oil on it wait overnight and get it out of there, install a new key. Iboats should have them.
 

S.A. Baker

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I was gonna say.....cranking with a not properly torqued flywheel nut will usually shear the key ! New flywheel key and proper torque, you should be back in business! Make sure you clean the crank taper and inside of flywheel taper thoroughly with laquer thinner or carb cleaner!
 
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