motor is sputtering and dying out

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Crosbyman

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btw.... just keep spaying a fuel mix in the carb face while you try the engine... if it runs OK as you feed it you know you have a fuel flow problem ... not an electrical problem. clean all fuel path , venting, etc...
 
M

Mc Tool

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Crosbyman said:
coils wise I have had success and sometimes doubts... some coils have 8 Kohms secondaries some have 4-5 kohms which I do sprefer for some reason. to test sparks has indicated by racerone .. all you nened is 2 nails 3/8 inch apart on a wood block one hooked up to the engine frame one to the spark coil booths (individual tests) ..
points must be CLEAN CLEAN CLEAN !!! (lots of comments on today'scheap and bad points compared to "still good" old stuff)
condenser wise lots of info on them at the AOMCI western site 4 excellent articles incl . M.Mohat 's suggestion to build a test box to check leakage with 250vdc with a simple "good--- no good" idiot lamp. I built one and it works great
see picture of one test box with fancy variable voltages. My identical design #1 version does not have the potentiometer dial but works fine!!
View attachment 420975




see articles to download in this link

View attachment 420973
Click to expand...
We used to have something similar in the early 80's while I was fixing small motors . Now you can buy a multimeter with a capacitor tester that not only tests the cap but can also measure capacity .... some are cheap enough for occasional use .
 
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Mc Tool

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Nordin said:
Mc Tool, I just asked for you out there about your experience about chinese aftermarket parts.
I have bought OMC style fuel pumps (the squer style) and these three was crap. Also bought chinese switchboxes for Mercury 3, 4 and 6 cylinders.
The same, crap.
Maybe wrong manufactor, I do not know.
BUT I was asking about you out there about your experience.
Know the chines OMC magneto coils are half the price but if they are failing after a year or so, than a good brand such as OEM, CDI Electronics or EMP is more worth the money.
Click to expand...
"I never use chinese made parts."
Now Im confused .
Well . as above I have had good experiances with my Chinese coils .
The truth is that a helliva lot of stuff is now made in China ...most o f it is OK , but like everywhere else there are some shonky bastards out there .
I look on various websites for parts ...find a good supplier ( not Caltec :D) and then see if I cant find the same thing on a Chinese site ....they often used the same set of images ...and buy cheaper.
Spend a bit of time looking about ....there is money to be saved :)
 
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Crosbyman

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gentlemen we are diverging from a sputtering engine to China quality..!
we need answers to wether or not the engine runs on carb face feeding of fuel mix. ! if it runs ok we can assume the coils and the rest are fine.
 
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Crosbyman

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Mc Tool said:
We used to have something similar in the early 80's while I was fixing small motors . Now you can buy a multimeter with a capacitor tester that not only tests the cap but can also measure capacity .... some are cheap enough for occasional use .
Click to expand...
Now you can buy a multimeter with a capacitor tester that not only tests the cap but can also measure capacity .... some are cheap enough for occasional


I have one but these meters which only has a low voltage battery like a 9vdc They are only good for establishing capacitance values (if not open or shorted inside) but unable to load test a capacitor like the m.mohat test box or similar commercial products
 
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Nordin

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Yes I know a lot of the aftermarket parts are made i China.
But if you buy a CDI Electronic part or OEM, EMP or other good parts you know it is good because they have a reputation to defend even if it is a chinese made part.
I do not defend good known brands against chinese not known manufactor.
Just want to know from you out there if chinese aftermarket parts are a challange or a good try.
If it is which suppier are good?

# Crosbyman, yes I know that there is a sputtering issue.
But to fix the issue we have to figure out if there is a ignition or fuel issue.
I just notice that the coils were not a OEM or in my opinion good brand.
That is why I start to ask about the coils and what supplier it is and quality it has.
 
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M

Mc Tool

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Crosbyman said:
Now you can buy a multimeter with a capacitor tester that not only tests the cap but can also measure capacity .... some are cheap enough for occasional


I have one but these meters which only has a low voltage battery like a 9vdc They are only good for establishing capacitance values (if not open or shorted inside) but unable to load test a capacitor like the m.mohat test box or similar commercial products
Click to expand...
Yes ,but it ( Fluke 179 ) has always done me for testing/measuring everything from start and/ or run caps and the wee stuff on circuit boards .
I have used my megger to charge up caps and then short them out ....more of a party trick :LOL:

TBH I never really thought about actual load testing ....usually if the cap measures out to be correct to the spec then good to go . My meter wont actually tell you if the cap is open or shorted....it just wont measure it so I know its a dud . :)
 
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Mc Tool

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Nordin said:
Yes I know a lot of the aftermarket parts are made i China.
But if you buy a CDI Electronic part or OEM, EMP or other good parts you know it is good because they have a reputation to defend even if it is a chinese made part.
I do not defend good known brands against chinese not known manufactor.
Just want to know from you out there if chinese aftermarket parts are a challange or a good try.
If it is which suppier are good?

# Crosbyman, yes I know that there is a sputtering issue.
But to fix the issue we have to figure out if there is a ignition or fuel issue.
I just notice that the coils were not a OEM or in my opinion good brand.
That is why I start to ask about the coils and what supplier it is and quality it has.
Click to expand...
Yeah its same with a lot of stuff ...like Harley Davidson , Stihl or Mercury etc are not going to endorse a piece of crap part so you get security in that . There are other options ....look at the reviews ( and deciphering the BS there is a whole nother skill ;) )
As for the coils in this instance ...the OP already has them so it doesnt matter what brand or supplier ,irrelevant now , and as above , give them the ⅜" spark test and if they pass muster they are as good as they can be . Honestly Dude I dont know how you can come to the conclusion that they "are not a good brand " by looking at a pic of them , we need to wait untill the get the acid test . :) I just think your a bit trigger happy thats all :)
 
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Dmknox98

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3rdtimesthecharm said:
I’d try using a V-shaped file on those crank threads before tearing it apart. I’ve had luck with that before.
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I'll try to take a picture later but there really isn't much threading left on those top 2-3 threads to repair. Looks like they got completely ripped off.
 
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Dmknox98

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Crosbyman said:
gentlemen we are diverging from a sputtering engine to China quality..!
we need answers to wether or not the engine runs on carb face feeding of fuel mix. ! if it runs ok we can assume the coils and the rest are fine.
Click to expand...
Well without anyway to get the flywheel to seat, as the nut cannot go back on the crankshaft, I have no way to start the motor at the moment. I'll have to try some repairs or get a new crankshaft. Might be till next week that I can get the stuff I need to try it out.

Might have to come back to it later and make a new thread later if I have to replace/make a lot of seals and gaskets.

All great info though. I will see about making the tester box.
 
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Mc Tool

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If its only the top couple of threads I be trying to fix it with a thread file .
But I guess if you really do only have 65 odd psi compression its going to need to come apart anyway , but if it only needs rings and a hone Id still be looking to fix it .:)
 
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Dmknox98

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Mc Tool said:
If its only the top couple of threads I be trying to fix it with a thread file .
But I guess if you really do only have 65 odd psi compression its going to need to come apart anyway , but if it only needs rings and a hone Id still be looking to fix it .:)
Click to expand...
Okay, I guess that makes more sense than tearing everything apart. It's all epoxied together pretty well so Its going to be a real pain.
racerone said:
?????-----Just use a file to remove the top 2/3 threads.----Put the nut back on.
Click to expand...
I'll try to get a file for it this weekend. See what I can do. I'll post a video later in the week if all goes well.
 
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