3.0L merc efi

[Blue197320]

i started my 23cc project. nothing special yet just taking out the wireing and stripping the console. ill have porn of that when i get started on the console. i bought this boat knowing the motor had a bad hole in it. well it was killing me to not know what it looked like in there so i took the head off last night.
what i want to know is, is it cost effective to rebuild a 3.0? whats the best way to do it? bore out all cylinders and put oversize pistons? (im leaning towards that.) i think this motor had an oil injection problem because all the cylinders have a problem. anyone who has taken this on please give me your opinion. im not afraid of rebuilding it and ive got the tools to do it.


this is the hole with 0 psi:


the rest of the holes have about 100 psi and look like this:


how much does it cost to get a block bored??
thanks for any input guys!!!

[eggsuckindog]

240 for boring all 6 .015 over as long as that 1 will clean up OK - just have it bored before you buy pistons, the guy will do it until its good - maybe .030 maybe not. Be sure and put Chris Carson Reeds in it best 120 you could spend - tell them i sent you, great guys to work with - their in Key Largo and will answer some rebuild questions too. I put a new oil pump and gear in just because of hours but thats optional about 250. The rest on the mains and seals are all minimal and you can get everything from Pro Marine and shipped to you via Mike@American Marine. I have a whole parts list with prices for a 2.5 but should be close, or go to Pro Marine on the net - those are list prices though not yours.

[Blue197320]

240 for all 6 is alot better than i was thinking. i was fearing 100 per hole. a set of pistons on promarines website was 700 with rings. so im thinking a little over 1200 to rebuild? what do you think about putting all new bearings in it? i probably should since im in there right?

[gofastsandman]

Evan,
I have to pull my powerhead as well as it seems the base gasket failed. Salt is hell and that area doesn`t get flushed.

What worries me is 0 compression. This means the piston is not moving. Maybe the rod broke into more than 3 pieces. Maybe not.

Machine cost is determined by what is found, and your goals.

Cheers,
GFS

[Blue197320]

the pistons moves sandy. i turned the flywheel to see all the cylinders and to check that the piston moves

[gofastsandman]

If your piston is moving why are you getting 0 comp?

[Blue197320]

im guessing because the cylinder wall is scored so badly. you cant see in the pics but that piston is destroyed. it seems to have a flat spot on it. thats why i think it was an oil injection failure. plus i know the previous owner started it with no water. i dont know how long he ran it for or anything.

[gofastsandman]

Even if it is scored badly you would see some compression.

[thehermit]

i bought this boat knowing the motor had a bad hole in it.

Hone one or do em all over?

[Blue197320]

i dont see any hole in the block. when i said "hole" i meant the cylinder. im hoping it just needs to be bored over and have new pistons and rings.