timing

**rock** · 05-24-2019, 04:54 PM

Bought motor from local dealer about to close. 25 year or more tech/owner built rotating assembly 2.5 150 Merc with 6 new pistons but never finished. Trigger had crack in arm so replaced with new. Spin motor and at idle about 8* atdc. Move trigger and timing light fires at same spot ( 8* ) then at a point of advancement signal goes away completely. This is what the trigger with the broken arm did also. I have never had a flywheel failure but is it possible the inner mags went wonky? Black 75lb 40 amp. This is the wiring that was on the motor and it may all be junk. This is just where I am starting.

Rock

**H2Okie** · 05-24-2019, 05:48 PM

could be bad insulation on trigger wiring taking signal to ground though seems a longshot shot that all 3 would be bad at once . I have heard of trigger pick-ups being wiped out by screws coming loose and making contact with flywheel CDI resistance test for trigger shows 800-1400 ohms and 4vdc + at cranking speed with a DVA meter . You'll have to pull the flywheel to inspect the trigger for damage and you can check the imbedded trigger magnets in the flywheel hub at that time . Could trigger damage could have been caused by what whatever cracked the advance arm?

**Jay Smith** · 05-24-2019, 05:49 PM

Very possible Rock , I’ve never had one act that way but your start-stop firing magnets on the inner hub might be weak .
Call me and I’ll tell you how to confirm those magnets health ...
832 597 2603
Jay

**Motv18** · 05-24-2019, 10:13 PM

Given the broken arm, I would definitely suspect the mags. Or that with the timing issue it is the wrong or incorrect mag pattern for that trigger set up.

Might also pull the whole top end clean and inspect. Get a check on everything moving right.

**Dave S** · 05-25-2019, 12:05 PM

40 amp glued mags... could someone have put them in wrong? If you need stuff I have plenty.....

**HStream1** · 05-26-2019, 06:19 AM

Ive had that happen several times Randy and it was always the Hub. One time I indexed the Hub 180 degs so the key aligned with another North magnet and engine ran perfect. The other times I simply swapped the Hub. I always travel with Three Flywheels when i head to a race. The Hub key will only line up correctly with 4 magnets. 2 North Pole and 2 South Pole. The Key needs to align with a North Pole magnet. One will be correct for the factory timing marks the other will be 180 degs out. I use a small Compass to determine the North Magnets when ever i disassemble a flywheel to Powdercoat. Compass swings south Its on a North Pole magnet.

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**rock** · 05-27-2019, 05:22 PM

First off, thanks for the ideas. Decided to switch to a 16 amp system which is what I should have done in the first place cuz it's going on a Hydrostream and not a bass boat with a bunch of electronics. Motor runs like a top. Thanks again.

As far as the 40 amp goes I did try several different flywheels and all three worked the same. Dropped one of them and broke a magnet so we don't have to worry about that one anymore. Motor was not on a boat but instead on a stand I built several years ago. Harness was new when I built stand but today I noticed it would not turn engine and after a couple tries motor turned over. Could not duplicate the failure but due to the bizarre situation I had I have to think the switch may have been the issue by maybe somehow restricting the voltage. Anyway thanks for the help.

Rock

**H2Okie** · 05-27-2019, 10:03 PM

Thanks for the update Rock glad you got it working . I bought an older 200 EFI a while back and put it on a stand so I could go thru it and check everything out . I wanted to fire it up right away on a hose and check the compression numbers after warming the block up to verify the reads the seller advertised . I rigged up a battery and used clip jumpers to energize the Key sw. purple to the engine/ECU and used a remote starter switch to crank it over .My problem was not starting but rather shutting it off . I had neglected wiring a switch to ground out the Black /Yellow wire . I am assuming you've got a carb motor so the key in the "Off" position would be grounding out the switchboxes to kill the ignition . Does a carb motor have a purple wire that comes hot with the key in the "ON" position like the EFI motors?