trigger assembly Mercury 240 efi

[spdbrd1998]

I found my trigger assembly wires are melted and broken I need to replace the trigger assembly How hard is this any write ups on how to do this ?

 

[Sportster-2001-951C-Stock]

I found my trigger assembly wires are melted and broken I need to replace the trigger assembly How hard is this any write ups on how to do this ?

Do you mean the crankshaft position sensor? If so, must be too much heat from engine parts? Is harness side damaged, or sensor side? If sensor side, then replace sensor and re-route wires, and find out why/what caused excessive heat, blocked cooling passages?

 

[spdbrd1998]

The harness side is melted close to the plug that goes to the ignition controller unit so I need to relace the trigger assembly now how hard is this thing to replace

 

[Sportster-2001-951C-Stock]

The harness side is melted close to the plug that goes to the ignition controller unit so I need to relace the trigger assembly now how hard is this thing to replace

Yeah sorry, I don't know on that one, I was thinking of a different motor. That trigger's under the flywheel, right?

 

[spdbrd1998]

Yeah it is under the flywheel

 

[Dr Honda]

Sorry.... I've been gone for 3 days....



Anyway... it's not hard. But, you need a flywheel puller, and a BIG breaker bar to remove, and re-install the nut on the end of the crank.


Once the flywheel is off.... remove the link on the throttle arm, and disconnect the wires. The trigger unit is (more or less) just sitting in the holder, under the flywheel.


Once it's all back together... check the timing, and adjust as needed.

 

[Sportster-2001-951C-Stock]

Assuming you have to disassemble some positioning linkage, try not to change the adjustment on any of the linkage pieces, otherwise the ignition timing will be off. The position of the parts in reference to the crankshaft and throttle is muy important.

So, just remove the linkage cotter pins or clips instead of unscrewing the adjusters, then you can reassemble in the same relative position.

 

[Dr Honda]

Assuming you have to disassemble some positioning linkage, try not to change the adjustment on any of the linkage pieces, otherwise the ignition timing will be off. The position of the parts in reference to the crankshaft and throttle is muy important.

So, just remove the linkage cotter pins or clips instead of unscrewing the adjusters, then you can reassemble in the same relative position.

You can't rely on that, when replacing the pickup. Since the HALL sensors are mounted in plastic... they can be off by several degrees. So... you MUST check the timing after.

If, you are taking the engine apart (for a rebuild) you can safely re-install the original pick-up, as long as you don't un-thread that ball link.

 

[Sportster-2001-951C-Stock]

You can't rely on that, when replacing the pickup. Since the HALL sensors are mounted in plastic... they can be off by several degrees. So... you MUST check the timing after.

If, you are taking the engine apart (for a rebuild) you can safely re-install the original pick-up, as long as you don't un-thread that ball link.

I would check the timing, yes, I see many motors where someone misadjusted the linkage. I think it's easy for the DIY guy to make this mistake, yet it's not mentioned!

I apologize, it was advised to check timing.

 

[spdbrd1998]

Ok I replaced the trigger assembly and I already have spark boat starts right up but how do I fix the timing now ? Just to make sure its correct I do have a timing light already but I never used one of this before

 

[Dr Honda]

It's outlined in the manual. But basically, you hook the light to the #1 plug, and check the timing angle at the flywheel. If has never been done on your engine before, you may have to put on the timing marks.

 

[spdbrd1998]

After I disconnect all the wires from the spark plugs exept 1 do I need to ground them ? How do I do this ?