View Full Version : What is a timing jumper

08-17-2006, 10:51 PM
"Hi All,

I am the proud new owner of a 1993 yamaha stern drive with the 3 liter (181 CID) 130 horse in line 4 cylinder engine. I believe it is a general motors engine.

According to the owners manual, I need to use a "timing jumper" before I adjust the timing to 4degrees before top dead center.

I can not find any discussion about a timing jumper for this ignition system.

I would really appreciate it if you could tell me what I can use as a jumper (just a single strand of wire?) and what should I connect the jumper to.


08-18-2006, 08:09 AM
"The jumper is used to put the motor into a zero advance state, so you can time it. If not, the motor will be retarded since it tends to advance itself during some idling conditions (like a vacuum advance on cars does).


08-21-2006, 12:15 AM
"Thanks Jeff,

Do you know what I can use for a jumper and where should I connect it.

Even Yamaha has not been helpful."

08-23-2006, 09:39 PM
"That's cause you don't speak Japanese, I guess. You HAVE to locate a manual for it and see what they tell you.


12-07-2006, 10:18 PM

I found and purchased a manual written by Yamaha for my 3.0L stern drive. It shows the timing jumper and how to use it.<center><table border=1><tr><td>[img]http://www.marineengine.com/discus/icons/mime_pdf.gif""" align=left alt=""application/pdf"">timing jumper
timing jumper 4deg btdc.pdf ("") (46.8 k)</td></tr></table></center>"