mm 445 crank but will not start

glvu

Member
Once again seeking your help. I started excavating some dirt yesterday with the bucket and push the engine too hard so it stopped. Try started it again but only crank but will not start. I am thinking it might the carburetor cause it is semi cover with gasoline on the outside. Can this be the cause (see pics) or I should be looking at some other parts.
31002.jpg
31003.jpg
 
Sir,
Start with the easy stuff. Pull the center coil wire and crank the engine. If there is spark, pull the air cleaner hose and apply some gas to a cotton rag and give the engine a whiff of fuel vapor. If she fires; check to see if the fuel is getting in to the carb before spending ten bucks for a carb gasket set and needle & seat.
An engine needs to crank, spark, and fuel. I hate to do useless things and spend money for nothing.
Be a cheapskate, like me.
Charlie
 
(quoted from post at 22:57:24 12/13/15) Sir,
Start with the easy stuff. Pull the center coil wire and crank the engine. If there is spark, pull the air cleaner hose and apply some gas to a cotton rag and give the engine a whiff of fuel vapor. If she fires; check to see if the fuel is getting in to the carb before spending ten bucks for a carb gasket set and needle & seat.
An engine needs to crank, spark, and fuel. I hate to do useless things and spend money for nothing.
Be a cheapskate, like me.
Charlie

I bought a spark plug (ignition )tester and plug it between the ignition coil and the center of the of the distributor cap. crank the engine and the tester lit up but faint and does not stay on continuous during the crank. Took the center plug and held it against the engine block and got a weak spark less then what I get from a bbq starter. Does this mean that my ignition coil is "weak".

I will test the resistance of the coil once I get a hold of a multimeter. Does anyone know the resistance of the coil for the two poles and between the poles and can the center contact?

Tested the spark from the distributor cap to the spark plug and got no light on the spark plug tester. Open the distributor cap and looked at the contacts. They seemed fine.

How do I remove the distributor and what should I be looking for?

Will try appling gas around the air cleaner tomorrow. Did not have time today.
 
"the tester lit up but faint and does not stay on continuous during the crank." Indicates weak spark. Light should flash on and off each time a plug fires, not stay on constantly

"Does this mean that my ignition coil is "weak"." Possibly, but necessarily. Put it at the bottom of the list of your suspects. 445 was 12 volts from factory and had a direct 12 volt coil. Should have about 3 ohms between the small + and -- posts and 6000 to 10000 ohms from either small post to center. If it is an old coil remove large center wire and clean the cavity with a small wire brush or drill bit. I've seen them get so corroded the wire doesn't make good contact.

With switch on, engine not running, you should maintain near battery voltage at input to coil. Wire between coil and side of distributor should have near battery voltage with points open and near zero volts with points closed.

" How do I remove the distributor and what should I be looking for?" Don't remove the distributor. Points can look good and still malfunction. Go by test in previous paragraph.

Is your battery well charged?
 
(quoted from post at 18:55:47 12/15/15) "the tester lit up but faint and does not stay on continuous during the crank." Indicates weak spark. Light should flash on and off each time a plug fires, not stay on constantly

"Does this mean that my ignition coil is "weak"." Possibly, but necessarily. Put it at the bottom of the list of your suspects. 445 was 12 volts from factory and had a direct 12 volt coil. Should have about 3 ohms between the small + and -- posts and 6000 to 10000 ohms from either small post to center. If it is an old coil remove large center wire and clean the cavity with a small wire brush or drill bit. I've seen them get so corroded the wire doesn't make good contact.

With switch on, engine not running, you should maintain near battery voltage at input to coil. Wire between coil and side of distributor should have near battery voltage with points open and near zero volts with points closed.

" How do I remove the distributor and what should I be looking for?" Don't remove the distributor. Points can look good and still malfunction. Go by test in previous paragraph.

Is your battery well charged?



I have a 5 star that stops dead once in a great while. cranks forever but wont start. I have to pull the cap and file the points. pops right off and runs great after that.
 
You guys were all correct. I cleaned the contact for each of the spark plug wires and the contact to the distributor cap. Fire up the engine, it crank but no start. Continue cleaning the contact under the cap and the distributor rotor, fire up the engine YES it started. total cost $1.49 for sand paper. Knowledge gain, priceless.

:D Happy. Thanks all.

P.S. measure the resistance between the + and - poles of the coil and got 1.6 ohms, measure the resistance between the center and each of the poles and got 10K ohms. coil is still good.
 
If a coil only shows 1.6 ohms across the primary, it needs a resistor in series with it in the 12 volts supply while running or you will be filing the points very regular and replacing them often.
Bryce
 
Resistor should approximately equal the resistance of the coil so 1.5 ohms coil 1.5 ohms resistor. Connect between ignition switch and coil.

NAPA ICR13SB should work.
 
Or get a NAPA IC14SB coil, no resistor required and simplify the wiring and eliminate one potential future problem.
 
(quoted from post at 23:30:11 12/17/15) If a coil only shows 1.6 ohms across the primary, it needs a resistor in series with it in the 12 volts supply while running or you will be filing the points very regular and replacing them often.
Bryce

I installed the recommended resistor (NAPA ICR13SB), see pic. I have couple of questions before firing the tractor up.

1st. I installed it between the ignition switch (I assuming the from the key and not the starter button) and
coil. I don't know if I connected them correctly because I am continuity between the two ends of the resistor with that of the engine block.

2nd. Does my Delco Remy coil( Part No. 1115202 — Part 6V/NO EXT RESIST - 12V/W/1957154) have a internal resistor. (see download spec.)
31514.jpg
31515.jpg
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top