470 mercruiser rebuilt engine install questions

mickyryan

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id say 19 gph if you flow anymore then that you would suck ya tank dry lol you will use at wot around 3 to 6 gph if that is any help
also I didn't do anything but put a t on my oil sensor to accept a secondary sensor then went from that to fuel pump if I crank boat more then say 5 revolutions I'm already tripping sensor and pump is running I do see added value in a relay but that also might be overkill since this seems to be way most folks have hooked theirs up over the years in auto industry
 

alldodge

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Do I need a 30 gph pump, or 19gph both are in psi range. 3-5 psi.

Either will work, the pump will not push more then the motor will use do to the internal regulator, but the 19 is plenty

Hope the 470 folks will answer your other questions
I know have another dilemma. I stumbled across some info about push rod lengths when checking out the merc head gaskets.

Said the rods can be different lengths. Well, I looked and one is longer than the rest and the some others seem to have very suttle length differences.

Im using rods from my parts 470 as the one I had built didn't have any when I bought it. Parts engine/head is from 1987. And like I said above my rebuilt head is a larger one.

1- so are the rods the same on the regular head as opposed to cobra jet head?

2- the rods must go in a certain orientation- if I can use the rods I have?
 

stonyloam

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On the Ford 460/Mercruiser 470 engines the valve lash is set by the pushrods length, because the rockers are non adjustable. You just put in a pushrod of the correct length and torque it down. As I understand it, to determine the correct length you drop in a rod, torque down the rocker with the valve closed and use a tool to collapse the lifter and measure the gap between the rod and rocker. If the gap is too large, drop in a longer pushrod etc. Your mechanic should know how to do it, and you can get the pushrods of various length from your Ford dealer. That is why it is important to know which hole each rod came out of in a normal rebuild. In your case you have no idea.

The 19 gah should be plenty.

Yeah the red wire would be used to activate the relay which would feed the pump directly from the battery. It will work without it, I just worry a little about the current draw through the pressure switch points.
 

mickyryan

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pushrods are varied length due to canted valve positions it should be very easy to figure out what pushrod goes into what hole longer ones will be on one bank and shorter ones will be on other if I recall in other words exaust are longer then intake for proper geometry of the valve train due to canted valves
 

aarons 470

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Ok will this switch work? (Link below) I think it's very common so I can get one at any auto parts store.

Also wondering if anyone has a link or part number to the relay I need?

I'm going to have more questions as I install my engine should I just keep using this thread or start a new one for different issues?

Link to pressure switch
https://www.amazon.com/Standard-Moto.../dp/B00153AZWY
 

aarons 470

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Looking at the diagram above- For the Solenoid and ignition switch wiring off of pressure switch.

can I tie them into something closer, (if so, what do you recomend) or do I need to run new wires all the way back to ignition and solenoid?

If I get a relay, where do I install it?
 

alldodge

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The oil switch listed in previous post will work.

Run a new wire from the starter solenoid small post with the Yellow/Red wire on it, and run to the NC post on the oil pressure switch.

The purple wire on the carburetor electric choke, run a wire from it to the NO post of the oil pressure switch.

I would keep using this same thread
 

stonyloam

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Sorry Dodgeman, it is a 470, ;) you need to run the wire from the SLAVE SOLENOID (small terminal) to the NC contact of the oil pressure switch to power the fuel pump during starting. I use a fuel pump relay to power my Petronix, and use a valve cover bolt through the tab on the relay socket to mount it. I get 12V from the large red wire on the slave solenoid.
 

alldodge

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Still think I have it right, The manual shows a starter solenoid mounted on the engine, and the starter does not have a solenoid mounted on the starter. The parts breakdown also confirms the same setup.
http://www.mercruiserparts.com/bam/subassembly/30928/1062/1

Now if the OP has the delco starter then it does have a slave and one mounted on the starter.

Now if the carb does not have an electric choke which the manual shows wiring for, the purple wire just needs to be found and used. If the wiring uses the BIA color coding, then using the main Red (direct battery connection) will not work, because it will keep the pump running with the engine off unless a relay is used.

I would find the White wire going to the positive side of the coil. This same wire will need to be found to energize the relay IF a relay is used.
 

stonyloam

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Yeah the early models did not technically have a SLAVE solenoid, the engine mounted solenoid was the starter solenoid, it became a slave when Mercruiser changed to a starter with a starting solenoid. The solenoid is the same, and the resistance wire bypass to the coil comes off of the engine mounted (slave) solenoid rather than the starter (as in most other Merc engines) and while attaching the wire to the starter solenoid (if he has one) would work, attaching to the slave would be the technically correct way to do it. If you decide to use a relay you can pick up both 12v and starting power from the slave making the instillation a little neater and easier.
 

aarons 470

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Ok, so the starter that came with my 82 glasply I'm going to use. It has nothing attached to it and doesn't appear to be missing anything.

My parts engine serial number c327066 has a starter with it, and it has a smaller unit mounted to it. So this would be the slave?

The older starter appears to be in better shape. So my plan is to use it. And the boat will be wired for it I'm assuming, it's all stock wiring.

So on my 82, is the slave the smaller solenoid attached to the block? Or is it
Just a selonoid?

So that being said, dodge your first post on this is correct, on how I should wire it up?

I bought a carb, it has an electric choke.not sure if boat is wired for it, but if it isn't I'll probably add a wire. I'll look tonight for a small purple wire.

Not much progress over weekend, buddy couldn't make it, and we had some snow.
 

aarons 470

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I noticed a switch that's sits behind engine. I think it's a safety switch when putting into gear? Should I replace it now, are they prone to failing?
Looks like it will be hard to get to once engine is in.
 

stonyloam

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If that switch has a little roller on it, it is the shift interrupt switch, that lets you take the boat OUT of gear by causing the engine to stumble a bit and reduce the pressure on the gears allowing you to shift into neutral. Read about it in the adults only section.
 

stonyloam

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OK. About the starter. On a boat there can be a long run from the ignition switch to the starter which can cause the voltage to drop due to resistance Of the wire. To overcome this potential problem most Mercruisers use a slave solinoid, which is a relay activated by the ignition switch (start) which feeds full voltage to the starter solenoid. EXCEPT of course the 470. On the early versions there was no starter mounted solenoid, there was only the engine mounted solenoid, which is apparently what you have on your earlier engine. On later models they went to a starter with a solenoid, but they kept the block mounted solenoid and that became the slave which fed voltage to the starter solenoid rather than directly to the starter motor, as in your older starter. That, by the way is why the 470 slave solenoid is different from most other Merc slaves, and why the resistance wire comes off of the slave rather than the starter. Problem is when the engine mounted solenoid is used to power the starter motor directly it is putting a huge current draw through relatively small contacts and starter wire. I would suggest that you use the starter with the solenoid and use the engine solenoid as a slave. Even if you have to get the starter rebuilt, IMHO it will be the more reliable setup.
 

aarons 470

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Ok thanks Terry. The newer starter did work it was in a boat that I stripped. Problem is it saw a lot of weather for a couple months, after pulling that engine I forgot it was still in the boat exposed. It looks pretty rusty now. But as you say I'll go with that one, I want the best setup I can get at this point, I want it dependable. It should fit just fine?
My setups have different flywheel housings, only thing really different. The engine mount centers are wider on the older setup which I'm using for the glasply.

So since I'm using the newer starter, can u give me another rundown on the pump wiring? Appreciate it.

Yes it is the roller switch I'll read up on it.

And I'll need to figure out the wiring with the different starter, (more to come on that) lol I apologize

Thanks
 
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alldodge

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Connect jumper cables to 12V battery.
Connect Ground of jumper cable to case on starter
Connect Positive of jumper cable to top large post
Use a screw drive or another large jumper wire and cross between the small terminal and the positive cable, it should engage the starter.

Make sure your hanging on to the starter tight or better yet put it in a vise
start.jpg
 

stonyloam

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All of the starters should be interchangeable, however depending on the year, the mounting bolts (or studs) may be different.
 

aarons 470

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Thanks as always guys. I'll test starter tonight, then hopefully can wire wheel and paint If it works. All my other pieces are painted up. Been using wire wheel and brake cleaner.
I warm up the cans of rustoleum in water, sprays well. And looks good, kind of has that old car laquer look.

I like the diagram, I can do that!
On the relay power, Can just run straight from battery with a fuse inline instead of going to a bus? Or is there a recommend spot off of the bus on the transom etc?

Do I use the fuel pumps fuse recommendation, or will this one off battery be larger and one right before pump be smaller? (If there is one there)

What's the older starter without helper worth to sell quickly? Appears to be in really good shape. I'll have to test it of course.
 
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