1979 MCM 260 5.7L 350cid Slave Solenoid

1979 MCM 260 5.7L 350cid
Serial# 5424302

I am getting inconsistencies with part numbers and replacement with the vendors, not sure if it's my mistake or theirs. Does it matter which style of solenoid this has? The one I am replacing has the posts that are in a over/under pattern and the one they are trying to replace it with has the four posts in a row.

It may also be pertinent to mention that I want to add in an electric fuel pump, if you look at the attachment you will see my plan to wire it in, not 100% sure if that's how I should do it. The manual has the purple with yellow going to the slave solenoid, I planned to wire it to the starter along with the new pump. Also, I want to switch this from an amp gauge to a volt gauge.


Ok scratch that I can't seem to up the pics I had ready so hopefully you can decode what I am trying to say without them.

Re: 1979 MCM 260 5.7L 350cid Slave Solenoid

any slave solenoid will work as long as you can physically mount it and hook it up.

to eliminate amp gauge route charge wire (orange??) to batt+ in engine compartment (could be at solenoid)

I personally would NOT use an electric pump unless it was an ignition protected marine unit AND it was wired to only run when the engine had oil pressure.... you also would need a prime feature, could be as simple as a momentary switch to run the pump manually.

Re: 1979 MCM 260 5.7L 350cid Slave Solenoid

It is a Mercruiser fuel pump I pulled off a 4.3L, here it is http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=809969%2096&ivar=images/COMMON/14280.png&inbr=1937&bnbr=60&bdesc=FUEL+PUMP+AND+FUEL+FILTER

So previously it was wired Red & Yellow/R on the two big posts and yellow/r & purple/y on the small posts....black(ground) was just attached to solenoid bracket. Now would I want to wire the two big posts the same, the small yellow/r the same, but have black replace the purple/y, then route purple/y to the starter where it would also meet the fuel pump?

As per the charge wire, will that be running through the breaker on the engine before going to the batt now or just straight over?

Re: 1979 MCM 260 5.7L 350cid Slave Solenoid

Here is some wiring diagrams I put together for the engine and helm area to change over from an ammeter to a voltmeter. Nothing really hard to do, just hard to easily explain. It's a 5 meg file, I left it big so you could enlarge the pictures without them getting all blurry.
http://www.4shared.com/office/ooPZcrK_/Ammeter_to_Voltmeter.html?

Also, here is the wiring diagram of how Mercruiser wires in the electric fuel pumps.

Re: 1979 MCM 260 5.7L 350cid Slave Solenoid

Hey thanks Don. I couldn't get to the 4shared page though....it kept failing to open. I'll try back again later though, maybe just a temp glitch.

Re: 1979 MCM 260 5.7L 350cid Slave Solenoid

It doesn't open in 4 shared, you download it to your computer then open it.

Never mind, I just went there to get a link for another post and the whole site isn't working.