JLO/CUYUNA Spark Problems - Snowmobile Forum: Your #1 Snowmobile Forum
http://www.snowmobileforum.com
Go Back   Snowmobile Forum: Your #1 Snowmobile Forum > Specific Snowmobile Forums > Vintage Snowmobiles


» Sponsors





Reply
 
LinkBack Thread Tools Display Modes
Old 01-15-2013, 11:33 AM   #1 (permalink)
Registered User
 
Join Date: Oct 2012
Location: Saskatoon, SK. Canada
Posts: 5
JLO/CUYUNA Spark Problems

I am working on a '76 JLO/CUYUNA 440 engine with spark on #1 PTO cylinder only. I have changed points & condensors, then disconnected external coils. Then I hooked up a continuity light hooked from the blue wire leading from #1 points to the corresponding external coil & ground. As the #1 points start to open the light dims just as it should. When I try the same with #2 points blue wire and ground, there is no change at all. I have checked continuity on the 2black wires coming off of internal ignition coil to both points, no apparent break in circuit.

This is the typical BOSCH stator used on points type ignition of the '70's, with a heavy wire internal lighting coil on left and then 2 coils stacked on the right with ignition being the bottom coil and then a small lighting coil on top.

Can anyone let me know what could possibly be causing me so much grief in diagnosing why the #2 points/condensor won't generate a spark?
cmorlock is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 01-15-2013, 03:02 PM   #2 (permalink)
Super Moderator
 
RJ Gleason's Avatar
 
Join Date: Feb 2005
Location: Groton NY
Posts: 32,285
If you isolate the components, does it show proper function?
The other option is that the charge coil is shorted out.

The single large coil is the lights and the paired is the left and right cylinder charge coil.
Test each for continuity and resistance.
__________________
Old Cat Rider
'93 Wildcat 700EFI
w/ Comet 108 Pro-4 clutch & 01 ZR skid

'90 Wildcat Project in progress.

Vintage (sorta)
1980 Indy Trail 440 (for sale)
1980 AC Pantera (donor engine to the 90 wildcat)


http://www.dcdrifters.net/


Worshipful Master; F&AM Dryden Lodge# 472
http://www.masonicdryden472.org/

Rules of this forum are strictly enforced!
RJ Gleason is offline   Reply With Quote
Old 01-15-2013, 05:19 PM   #3 (permalink)
Registered User
 
Join Date: Oct 2012
Location: Saskatoon, SK. Canada
Posts: 5
From my manual the single coil on left is lighting 120 W, the top to the two paired on right is also a small lighting 30 W and then the lower coil on right is supposed to be ignition which makes sense as this is the only coil which has wires going to condensors and points. The others have yellow and green wires which are supposed to be for lights.

If what you are saying about the 2 coils on right being 1 for each cylinder then I have been tackling this all wrong.

If I have been correct in what I think each coil does:

Tell me this, if I unsolder both black wires coming off of the bottom internal ignition coil from the condensors and test for continuity and or resistance any idea what kind of values I should expect?

Also is it possible the lead coming off top end of this coil which goes to #1 could be good and the lead coming off bottom which goes to #2 could be bad? I guess what I am thinking is the actually 2 separate windings in the internal ignition coil 1 to service each coil and points? Or am I way out to lunch?

I have to go out tonight but I look forward to your thoughts on this set of questions.

Craig
cmorlock is offline   Reply With Quote
Old 01-16-2013, 07:11 AM   #4 (permalink)
Super Moderator
 
RJ Gleason's Avatar
 
Join Date: Feb 2005
Location: Groton NY
Posts: 32,285
I might be incorrect as to your particular system, but most are as I described.
I have seen a dual output coil be good on one end and bad on the other. A continuity check would show this as it would be open. I do not have any Ohms values for those.
__________________
Old Cat Rider
'93 Wildcat 700EFI
w/ Comet 108 Pro-4 clutch & 01 ZR skid

'90 Wildcat Project in progress.

Vintage (sorta)
1980 Indy Trail 440 (for sale)
1980 AC Pantera (donor engine to the 90 wildcat)


http://www.dcdrifters.net/


Worshipful Master; F&AM Dryden Lodge# 472
http://www.masonicdryden472.org/

Rules of this forum are strictly enforced!
RJ Gleason is offline   Reply With Quote
Old 01-16-2013, 08:59 AM   #5 (permalink)
Registered User
 
Old Man's Avatar
 
Join Date: Dec 2007
Location: Dinorwic Lake, Ontario
Posts: 452
I think RJ is right. This attached link to a JLO Service manual shows the magneto as he describes it.

http://www.vintagesnow.com/Engine_ma...F-440-3_SM.pdf
Old Man is offline   Reply With Quote
Old 01-16-2013, 05:02 PM   #6 (permalink)
Registered User
 
Join Date: Oct 2012
Location: Saskatoon, SK. Canada
Posts: 5
Could you fellows check out this manual:

http://www.vintagesnow.com/Engine_ma...F-400-6_PM.pdf in the CUYUNA/JLO/ROCKWELL list on Vintage Snow.

If you look at page 4 and the parts break down, you will see why I am confused. Item 6 is shown as 100 watt & 7 as 20 watt lighting coil. Item 8 is shown as ignition coil.

My engine is actually a 2F-440-7,8 or 9, but I am not at home right now to check for sure. I know from the manual I have (for '76 Massey Whirlwind made by Scorpion which this engine is from) the watt values of 6 & 7 are highter .

This leads to my current confusion about what items 6 & 7 actually do on my engine.

All thoughts and suggestions appreciated.

Craig
cmorlock is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Powered by vBadvanced CMPS v3.2.2

All times are GMT -5. The time now is 08:24 PM.



Copyright SnowmobileForum.com

Search Engine Friendly URLs by vBSEO 3.6.0