Project Swap..93 3.0LX Mercruiser swap to a 86 Mercruiser 140 (part 2)

[buckz6319]

I have decided to continue my project swap, after much encouragement from forum members and my wife...so here we go with Part 2

I'm starting with the wiring issues..

Question: Should I remove the wiring harness from this 86 Mercruiser 140, and replace it with the one from the 93, which would include all the updated electrical components that I know worked?... If it can be done with minimal modifications then disregard the rest of this post.... and i will start to the transplant

if it can't be done, then I will continue to work on the issues below...

I am now trying to figure out the wiring on this alternator. I have the wiring diagram from the Mercruiser FSM, and it doesn't show the blue wire coming off the Voltage regulator.

The alternator is vary hot to the touch, but is not making any bearing noise, and i have no juice going to the battery, so something is wrong.

I do have a purple wire that is not hook up to anything that is just sitting on top of alternator. The wiring diagram is showing it connects to the Ignition switch +12V, choke, and +Positive coil.

I'm not sure if this the correct alternator for this 140? the one that i took off the 3.0LX   

I also have two wires on the +Positive coil that are warm to the touch, not hot, but warm.
here are some pics



 

[Rich_V174SS]

Should I remove the wiring harness from this 86 Mercruiser 140, and replace it with the one from the 93, which would include all the updated electrical components that I know worked?...

I would use the newer harness if possible. I don't know if the older harness has the same pin-outs to connect with the main harness in the boat.

I also have two wires on the +Positive coil that are warm to the touch, not hot, but warm.

The two wires - one is the ballast or resistance wire. It probably connects between the electric choke heater and the coil. It's fine that it should get warm. The other wire should connect to the small left-hand lug on the starter. This is the bypass wire that circumvents the resistance wire when cranking the engine.

[buckz6319]

Should I remove the wiring harness from this 86 Mercruiser 140, and replace it with the one from the 93, which would include all the updated electrical components that I know worked?...

I would use the newer harness if possible. I don't know if the older harness has the same pin-outs to connect with the main harness in the boat.

I also have two wires on the +Positive coil that are warm to the touch, not hot, but warm.

The two wires - one is the ballast or resistance wire. It probably connects between the electric choke heater and the coil. It's fine that it should get warm. The other wire should connect to the small left-hand lug on the starter. This is the bypass wire that circumvents the resistance wire when cranking the engine.

yes, so I know that the wiring is correct for the coil
thanks!

[Rich_V174SS]

Why not use the alternator from the newer engine too? It should a piece-o-cake to hook up the wires if you're using the newer harness.

[buckz6319]

Why not use the alternator from the newer engine too? It should a piece-o-cake to hook up the wires if you're using the newer harness.

Rich, if the newer harness will work, then I will transplant it to the 86, but i didn;t know about the harness connector pins will be the same

[Rich_V174SS]

I would be looking at like like a long-block replacement - swap everything good from the 93 engine to the 86 engine to eliminate the possibility that something will not quite connect in the boat.

[buckz6319]

I would be looking at like like a long-block replacement - swap everything good from the 93 engine to the 86 engine to eliminate the possibility that something will not quite connect in the boat.

thanks! It looks like the harness pin numbers and placement are the same according to the 3.0LX EST Ignition Diagram, and the 3.0L

I will disconnect the wiring harness at the connector on the 86, and see if the 93 will plug in. I will do that tomorrow

[Jason]

I would be looking at like like a long-block replacement - swap everything good from the 93 engine to the 86 engine to eliminate the possibility that something will not quite connect in the boat.

I agree. I would go this route as well. Your newer engine has the better ignition system anyway.

[buckz6319]

I will be doing the transplant: )

I will also be removing the manifold and riser to have a look see, they are original to the engine, is what I was told, and if bad i change them

[buckz6319]

I have a few question that I would love to have the answers too.

Question 1. With a one piece rear main seal on the 86 140, and a two piece rear main seals on the 93 3.0, are the flywheels interchangeable?

Question 2. Does the 86 140 flywheel, have the 3 threaded holes that would allow the triangle coupler to bolt to?

Question 3. Can I use the 93 3.0 bell housing on the 86 140? if so is it a direct bolt on?

trying to plan ahead, and figuring things out as I go...

thanks for the help:)

[Rich_V174SS]

This might cover all your questions in one shot:

I know somewhere along the line Mercury changed the diameter of the flywheel, perhaps when they went Alpha One Gen 2 in 1991. That being the case the starter will be particular to the flywheel so the drive coupler may also be particular.

[buckz6319]

This might cover all your questions in one shot:

I know somewhere along the line Mercury changed the diameter of the flywheel, perhaps when they went Alpha One Gen 2 in 1991. That being the case the starter will be particular to the flywheel so the drive coupler may also be particular.

thanks rich!
so, I keep the flywheel, coupler and starter on the 86 140. 

do you or anyone else know if the bell housings are interchangeable?

[75starflight]

This might cover all your questions in one shot:

I know somewhere along the line Mercury changed the diameter of the flywheel, perhaps when they went Alpha One Gen 2 in 1991. That being the case the starter will be particular to the flywheel so the drive coupler may also be particular.

thanks rich!
so, I keep the flywheel, coupler and starter on the 86 140. 

do you or anyone else know if the bell housings are interchangeable?

From looking at parts breakdowns on line the flywheel housing between the 86 and 93 are the same part number and will interchange. So which ever one you send to me doesn't matter. 

[buckz6319]

This might cover all your questions in one shot:

I know somewhere along the line Mercury changed the diameter of the flywheel, perhaps when they went Alpha One Gen 2 in 1991. That being the case the starter will be particular to the flywheel so the drive coupler may also be particular.

thanks rich!
so, I keep the flywheel, coupler and starter on the 86 140. 

do you or anyone else know if the bell housings are interchangeable?

From looking at parts breakdowns on line the flywheel housing between the 86 and 93 are the same part number and will interchange. So which ever one you send to me doesn't matter. 

Thanks, Brandon
I will send you the one from the 93, it is aleady removed.

[75starflight]

This might cover all your questions in one shot:

I know somewhere along the line Mercury changed the diameter of the flywheel, perhaps when they went Alpha One Gen 2 in 1991. That being the case the starter will be particular to the flywheel so the drive coupler may also be particular.

thanks rich!
so, I keep the flywheel, coupler and starter on the 86 140. 

do you or anyone else know if the bell housings are interchangeable?

From looking at parts breakdowns on line the flywheel housing between the 86 and 93 are the same part number and will interchange. So which ever one you send to me doesn't matter. 

Thanks, Brandon
I will send you the one from the 93, it is aleady removed.

Your welcome Dwayne.
Just remember to remove everything you need before you send me any parts.

[buckz6319]

No problem, Brandon
I'm looking forward to pulling the engine tomorrow afternoon .

[buckz6319]

Got her out!
it is... HOT, HUMID, and HOT here to day...and I get tired of working in the dirt too. I think I have done this kinda stuff in the dirt for 8 years here, thought i would get use to it....NOPE! lol



and Brandon are a few pic of the 93 Flywheel housing I'll be sending you

[75starflight]

Looks good Dwayne! On both!

[buckz6319]

Looks good Dwayne! On both!

thanks! I sent you an email..

[buckz6319]

I will be swapping wring harness, and all components that i can tomorrow, if it don't rain.

I also plan on removing the intake/exhaust manifold, and riser. The riser is leaking, and that is not a good sign.

I am sure that I will find other issues, and will update as I go along...

thanks for all the hepl:)