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1970 9.8 coil problems??

J

Jerry1234

New member
My old Merc(1970 or 71,Thunderbolt Ignition) doesn't want to start when it is wet. Leave the cowl off for a couple hours, starts great. Wires seem to be good, reading 0.0 to 0.1 ohms with meter set on 200 ohms. Both coil primary circuits show 0.1 ohms. I can't seem to get any ohms reading on the secondary circuit of either coil. Spec says secondary should be 800-1100 ohms. One coil is a 336-3950 and the other is a 336-4528 and both look good on the exterior. I have sprayed all wires and coils with ignition spray, but obviously it didn't help. Questions..1 Why am I getting no reading on the secondary circuit?..2 What can I get for replacement coils?..3 Is there something else causing this problem? I have had this engine for 25 years and it has always started and run great. My old fishing buddy,(R.I.P.), bought it new in '70 or '71. Any help would be greatly appreciated. Thanks, Jerry.
 
Jerry1234 said:
I am in Fredericton, New Brunswick, Canada
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More info.....The S/N is 7000026 and my old mechanic thought it was a '71 or '72 but he couldn't find it listed. The first coil number is 336-3955, not 50. It is a model 110. the part number on the coil mounting bracket is 56532.
 
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You need to check everything with a DVA meter--an ohm meter doesn't really do much. You present ohm meter can be used with a DVA adapter ($30) available from Amazon.

Jeff
 
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