225 ymis prime start problem

[livebaitdrifter]

Prime start not energizing solenoids.
I understand that the Plc energizes solenoids during cranking in conjunction with thermo sensor.
Thermo sensor working ok timing changes idle lowers after warm up.
Am I correct that voltage at solenoids constant and Plc switches low?
If then voltage should be?
Threw what wire is cranking voltage read byPLC(ymis)?
Thank you
Livebaitdrifter
Ps I changed the key switch, I scrapped a oem switch from a binnacle I had ,this is a remote controlled key, I switched wires from old switch but no blue wire on new switch, was that choke? Don't think this has anything to do with it because prime start didn't work from beginning of season after I rebuilt it.

 

[99yam40]

Re: 225 ymis prime start problem

Maybe this will tell you what color wires do what Wiring Color Codes for YAMAHA Outboard Motors.

Never heard of prime start solenoids, but have heard of prime start heater units that receive voltage only while motor is running, to heat up and close off the enrichment for cold start and warm up.

But I know nothing about a 225

 

[livebaitdrifter]

Re: 225 ymis prime start problem

I looked it up in diagram, they look like coils. I put some thought into it and the coils should have continuity threw them and they should energize if low side is grounded while key is on and should have continuity to ground while cranking and motor is cold. These things I will test tomorrow.

 

[99yam40]

Re: 225 ymis prime start problem

I would recommend getting a Yamaha service manual for your motor, it will have the testing procedures for all the systems and the specs

 

[Capt Ken]

Re: 225 ymis prime start problem

Would be nice to have a model number but I'm going to assume this is a carb'ed engine. You have six enrichment solenoids that is pressurized by the electric fuel pump. If you want to be sure it's that, there is a manual valve on the port side of the engine. Everything is governed by the temp sensor.

 

[livebaitdrifter]

Re: 225 ymis prime start problem

I'm very sorry for starting this thread without the model number or year.
It's a 1991 225. 90 deg, first year prime start.
My assumption was that the prime start wasn't working electrically because when I used the manual enrichment valve
It started, wrong. I tested yellow wire to PS, it had 12 volts, purple wire is ground or switched low, it had continuity to ground
During cranking, and the coils had 20 ohms.
Since everything electrically checked out I disassembled the pump and the diaphragm was wasted.
2 gaskets and an oring $42.50
I'll post again after I reinstall the pump.
Thanks to all who replyed
Ps the blue wire was choke, not used with prime start.