Picked up a replacement 3.0 motor

[demian5]

I found a complete motor locally for my CVX16SS as mine broke a valve at speed and damaged the piston. This one is supposed to run. under the valve cover is really clean with fresh oil in the rockers still. I only need the long block as my boat is a mercruiser. I picked it up for a great price and less than a replacement head will cost.

My plan is to do a compression test, then pull the head and put at least stainless exhaust valves in it and get the head done. Ill also pull the pan and inspect a couple bearings and see if the timing gear was upgrades to aluminium.

On the OMC pan there is a oil drain tube that comes up and has a cap on it. This appears it can get the oil out at the lowest point using a siphon. However I may need to change my pan over to this one. And if I do, ill pick up one of the oil train hoses that you leave in the bilge.

Any other suggestions?

This also means the bolt on stuff like the manifold, mounts, bell housing, etc, are up for grabs if anyone needs anything.

[Jason]

You could hook a hose up to it.remove the hose to the manifold and cap it off. To make sure there are no obvious cracks in the cooling system. I also don't see any reason you couldn't use the OMC oil pan. May also not hurt to see if you can get it to fire or run before really tearing into it. Listen for knocks.

[demian5]

May also not hurt to see if you can get it to fire or run before really tearing into it. Listen for knocks.

Great advice. I was on the fence with that.

[demian5]

Oiled down the cylinders and hooked up a mechanical oil pressure gauge:

Engine was not frozen and cranked over right away with the starter.

Compression readings:
#1 160
#2 160
#3 160
#4 150

Oil pressure while cranking was 40 psi.

Added a gas can to the fuel pump, put some fuel down the carb and it fired right up. Idled OK and hit on all cylinders. Valve train seemed a little noisy but it was hard to tell with an open exhaust running in the bed of my truck. Definitely no knocks.

I'm still pulling the head, pan and timing cover. Maybe its been rebuilt and has a metal cam gear already.

And the OMC has a goofy oil drain tube that connected to the drain plug and comes up by the dipstick tube. Has a cap. I guess that the vacuum drain the oil more thoroughly.

[Jason]

That’s good!
I’d keep that oil pan. The mercruiser dip stick tube on my 140 doesn’t go all the way down so I installed a hose to the drain tube where the drain plug is that you put through the bilge drain on the boat.

[75starflight]

That’s good!
I’d keep that oil pan. The mercruiser dip stick tube on my 140 doesn’t go all the way down so I installed a hose to the drain tube where the drain plug is that you put through the bilge drain on the boat.

I second Jason. I did the same with my 140 and have a hose to run out the drain.

[demian5]

I second Jason. I did the same with my 140 and have a hose to run out the drain.

That's what I want to do. But this tube actually goes to the drain plug. It has a cap on it. Its at the bottom of this picture. Ill get a better picture as Im working on the motor, but it appears it is to vacuum suck it out from the lowest point.

[demian5]

Also, is the sierra engine gasket kit going to be good enough? Ill only be running in fresh water.
Do I coat the head gasket with copper or anything when installing? I figure the rest of the gaskets, I just install like a car, little to no silicone.
I have read that if the timing gear has been upgraded to aluminum from nylon, it makes the engine a bit noisier. Is this true?
Can I use a car replacement water pump for the motor?
Is it smart to upgrade to stainless exhaust valves?

[Jason]

Either way you go with the hose through the bilge or pump through the OMC dipstick will work fine. Both are better than the OEM mercuirser design.
I've had enough bad luck with Seierra parts that I won't use any of their parts. I'd use Merucry gaskets. All gaskets go in just like a car.  I don't understand the reasoning behind SS valves.

[75starflight]

Go with standard Valves. I spent the money and went with stainless valves when i built my 140, I won't do it again, it is not worth the expense.

Also to answer your timing gear question, yes a little more noise until the set is broke in then it settles down.

[demian5]

Update. I believe I got a really good rebuilt motor already...

[demian5]

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