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97 Merc 40 4cyl 2 stroke WILL NOT START

B

Bill K

Contributing Member
I have done all the basics
it has 120 psi all 4 cylinders
It has spark at all 4 new plugs
gas in getting into the carbs
I have checked the kill circuits
I did the timing checks per the manual
The starter spins it very fast but it will not even gasp
I changed the voltage regulator a month ago becuase it was burned and dripping goo all over the place
It ran perfect one day and the next time it would not start
what can I do now????
 
Check the operation of the choke / enriching system.-------------Squirt some gas into the carburetors and see what happens.
 
I forgot to mention I did that too, even took a shot and sprayed some starting fluid in to see if it would fire, nothing
 
...it has 120 psi all 4 cylinders
It has spark at all 4 new plugs
gas in getting into the carbs...
Click to expand...

Spark or fuel may not be correct. Have you rebuilt the fuel pump? What does the spark look like? Blue or white/yellow?
 
Don't know why, but I am suspecting spark, I cannot tell if the spark jump is white or blue very hard to tell the difference for me.

Is there a simple check to tell is the stator is working correctly. I do not see anything amiss or dripping from it.

A month ago I changed the voltage regulator, it was burned and leaking all over. I changed that becuse it was not charging or running the tachometer, after the change it was charging and running the tach, WHAT COULD MAKE THAT GO BAD???
 
Test spark by establishing a 7/16" gap for the ignition system to jump ----------------Less tan that ( only jump a gap on plugs ) means that you have ignition trouble.
 
I have this speark tester that test spark under pressure
011.jpgthe spark will jump that gap at the green line indicated pressure and a little higher pressure it becomes intermittent anything above the middle of the green no spark the spark color appear to me to be white to purplish
 
re fuel pump should the fuel squirt out or dribble out?
I have several tools but do not have a DVA or any way to test the stator or trigger and all the merc dealers are booked up for the nest two weeks
I really want to go fishing and this motor is getting very frustrating
 
Got a younger neighbor to look at the spark on the plug electrodes and he said the spark is very weak, he can barely see it, we tried it on all the plugs and it is the same very weak white spark on all plugs. I guess my 70 year eyes are not as good as I thought
 
Several questions

When checking the timing using the starter to spin the motor what should the setting be?

Is the Flywheel installed with a KEY, the manual I have does not mention a key?

The manual does not mention in it anywhere anything about REED VALVES?
 
I don't know if there is a key in there or not, still trying to figure a way to hold the flywheel still while I break the Nut loose, any ideas there

What about reeds, where are they hiddem?
What should that timing mark be?
 
Hello Mr. Bill K
Try to put a long handled big flatscrew driver in the ring gear and hold against the starter to hold the fly wheel.
The reeds i belive are in the crankshaft on your motor.
the timing i'm not to sure what it is.
 
Used an impact wrench and got the nut off the flywheel with just a trigger pull and yes it does have a key to hold it in position
 
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