Test run a Mercruiser 3.0 ltr 86 model in the garage

[totx]

How much support the engine need for a test run in the garage to be safe?
(Does it need to be bolted down to a pallet ore something)

Any easy trick for start and stop, wiring switch?
Minimum to not damage anything, and perform a safe stop of the engine.

I would just use a multimeter for oil pressure and cooling temp.

What is the violet wire in to the merc carb?
And how should this be wired for test start/running)

The starter was disabled when I got the engine, is the solenoid "m" terminal in use, and what color on this wire?
And what color on the solenoid "s" terminal.

Hard to read color on the old manual, and better safe than sorry

 

[JustJason]

Re: Test run a Mercruiser 3.0 ltr 86 model in the garage

Since 3.0's rock and roll at idle speeds, you need a fair amount of support. I wouldn't even try it on my 2000lb engine stand. Your going to need to buy/fabricate an engine cradle out of steel for that.

Any easy trick for start and stop, wiring switch?
Minimum to not damage anything, and perform a safe stop of the engine.

Ya... a remote start switch to start the sucker then a temporary inline toggle switch to power on/off the coil.

I would just use a multimeter for oil pressure and cooling temp.

I don't know about that... Fluke does make a pressure transducer for their own meters. It's fairly expensive and I have no idea if it will work for oil pressure... You need a set of mechanical gauges for that. For temp, an IR pyrometer is your best friend for that. But realistically... if your running the engine on a cradle you wont even come close to real world operating temperatures unless there is something really really wrong with the engine.

What is the violet wire in to the merc carb?
And how should this be wired for test start/running)

The starter was disabled when I got the engine, is the solenoid "m" terminal in use, and what color on this wire?
And what color on the solenoid "s" terminal.

No idea... and I don't care to explain the rest. But I will tell you in all honesty because this is my job (and hopefully you can take this with an ounce of humility) If you don't know how to hook up a remote starter button to the starter, or how a choke works, or need "colors" of wires to make a starting system work, your probably in over your head, and will most likely hurt yourself when this engine flips over on a stand/poorly made cradle. I would just hate to see anybody hurting themselves or their wallet on advice given on iboats.

 

[ken_23434]

Re: Test run a Mercruiser 3.0 ltr 86 model in the garage

I started my 3.0 sitting on the garage floor. I did not bolt it down to anything. The rear mount was sitting on a 2x6 or some similar sized block of wood to hold the engine level. I bought the engine used and that block was already there. I was not concerned with the engine just rolling over when I started it. If you are concerned, I would just use a 2x4 (or similar) about 4 feet wide or so on the front mount. But, I had nothing when I did mine. My only real concern was the exhaust just dumping right there and making sure I had a fan to blow the fumes away.

Make sure you run a garden hose to the raw water in hose. The water will dump out the exhaust port.

Check out the --Adults Only Sticky-- and download the manual for the engine. I think it is manual #10. It has wiring diagrams available.

An extra ignition switch, or taking the one out of your boat would be enough along with a few feet wire to get to the engine. Otherwise, you can purchase a "remote starter", but I think that is wasted money. An extra ignition switch might be needed someday anyways, and much cheaper.

The violet wire is the wire that energizes the choke coil to start heating it up. Per the drawing it is tied in with a few other violet wires in the engine wireing harness.

Are you missing the entire engine wiring harness?

Anyways, Manual 10 chapter 4 will have all your answers about the wires.

The multimeter idea for monitoring temperatures seems fine to me. Just make sure you have a cheat sheet with the meter values to actual monitored values. That info is available in the manual too. That way you know that XX ohms is bad instead of calculating it while the engine is overheating to find out it was bad.

 

[navis]

Re: Test run a Mercruiser 3.0 ltr 86 model in the garage

We have test run several marine engines on the ground. All we did is hook up a ground wire from somewhere on the engine, any bolt will work, to the negative terminal on the battery. Then the main positive lead on the starter is hooked up with another thick wire (0-2gauge). Then two aligator clips.... attach one clip to the positive on the coil, then to the positive on the battery (this is now the equivalent to the ignition in the 'run' position. Then attatch an aligator clip to the positive in on the solenoid and bump the other end onto the positive terminal on the battery, this will crank the engine over and start it.

We ran all the engines just sitting there with some blocking under them and still attatched to the lift. Make sure you have water going to the cooling system, even though it wont heat up very hot, you will still cook your impellers.

Here are a couple video's of our system:

http://www.youtube.com/watch?v=3QYMC76yodo&feature=related


http://www.youtube.com/watch?v=NWf2bwkBO18&feature=channel

 

[totx]

Re: Test run a Mercruiser 3.0 ltr 86 model in the garage

Thanks for all the excessive answers

And sorry for some off the stupid question ;-)

Think this should answer all my question.
And it was an easy cheap way to do it...

I have changed a engine block and the engine was not dismantled by me.
Should have everything needed and got the manual.

Would not start without cooling, and actually do the start outside the garage.

But not ready to test yet...