1500 Mercury Blue Band Cracked Block Watter Passage

[frankenmerc]

Guys ,I recently purchased another in line 6.I found this one and it looked rough and went against my better judgment after speaking to the owner quoting he was a Christian and would not steer me wrong after all the compression was 120 on all 6 . all said and done I purchased it cause I wanted a 150.
After getting it home and verifying the compression cleaned her up and pulled the power head to get started with the restoration, well after in it for a couple days and feeling pretty good about it I was pulling the front water jacket cover to replace it due to a hairline crack in it. After breaking all the bolts in it and getting them all out but 3 left to drill I noticed this crack in the block next to the #5 cylinder on the side of the block.:mad-new:
Comp test
#1-110
#2-110
#3-116
#4-116
#5-115
#6-115
I am posting pictures ,please tell me what are your thoughts on this one? Do I scrap it ? Can it be welded?
Should it be welded? not sure which way to go from here.
Cant blame the guy I got it from chances are he did not know, I want to believe that any how.
Any advise or input would be appreciated ,never had this to deal with.

 

[oldman570]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

It sure looks as tho that crack extenes down inside the block aways. Your best bet would be to take it to a good welding shop and see just what they think they can do to fix it. You might be looking at scrap and a parts motor. JMO
Oldman570

 

[Chris1956]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Agreed, Take it to a good welder, and see what he says. As for the water jacket cover bolts, a lot of times you can drill thru the block casting and install nuts on the 1/4" cover bolts, and thru bolt them. Earlier Mercs had this feature from the factory. later blocks had tapped holes, but could still be drilled thru. The lowest bolts were tapped on all blocks, if I remember correctly.

 

[frankenmerc]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Thanks old man 570 and chris 1956, after another look that crack goes down pretty far awfully close the cylinder,my concern is that if it is welded and not drilled the crack will continue to travel.
I am not sure i want to risk my time and money into it,i do have another block that is in ok shape but will need to be bored due to some scoring and is a 1150,would it be possible to use this one and take all internals and electronics and put on the other?woulld i have to change pistons and rings.
The serial# to the block i have is 3945429 (1150) and the on.
e that that has th crack 4257477 (1500)
Thanks

 

[Chris1956]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

As long as they are both distributor ignition models, the electronics, internals, crank and pistons will fit. After you bore the cylinder(s) on the 1150, you will need an oversize piston and ring set. If the 1500 already has oversize pistons, maybe you can match them up to the cylinders you are boring. Get new rings if you can.

 

[buzzm19]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Oldman, make sure that the bottom of the blocks are the same, the exhaust ports are different on some blocks as mercury used this for different horspower applications. I have a 1971 l6 135hp and 1972 l6 140hp and the exhaust ports on the bottom are different and the side cover is also different. Buz

 

[frankenmerc]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Thanks Buzzm 19 I will be sure to check that out as well ,it seems as though I have a task on my hands if I want to salvage this one.Another question in my mind is the block and bore are the same what is giving me 115/150 hp reeds/carbs?and thanks to all that replied sounds like great advise .
Merc#1

 

[buzzm19]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

merc#1, you can't make a 115 into a 150, by reeds or carbs, Mercury made the changes in hp's through exhaust porting and that can't be accomplished even by experts (exhaust castings are different). Your compression is on the low side, my 140l6 is in the range 130/140, as long as the compression readings are within 10% you should be ok. If you read up on MB's engine rebuild you will get a lot of info from what he has done. Buz

 

[Laddies]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Not all 115 blocks can be converted to a 150, the block must be one with the fingerporting in it

 

[frankenmerc]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

merc#1, you can't make a 115 into a 150, by reeds or carbs, Mercury made the changes in hp's through exhaust porting and that can't be accomplished even by experts (exhaust castings are different). Your compression is on the low side, my 140l6 is in the range 130/140, as long as the compression readings are within 10% you should be ok. If you read up on MB's engine rebuild you will get a lot of info from what he has done. Buz

Ok,so it is in the porting i got that,thanks for explaining.read up on MB's engine rebuild?compression low?it is within 5.5% that dont seem too bad to me but i am far from an expert.I have a very rare looking 90 i bought last summer that belonged to guy that he inherited from his grandfather that stayed in storage for many years that has only 120 on all 6 so the readings you have are great.

So if i am understanding right if i use the 115 block with the 150 internals i will have a 115?

 

[frankenmerc]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Darn, Wrong Photos sorry.
ladies,not sure what you mean by fingerporting an how can I determine this?
Thanks

 

[Chris1956]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

Yes, 150HP pistons rods etc, in a 115HP block will put out 115HP. The 150HP pistons may have a boost port, but your block will not have the porting to use it.

 

[Laddies]

Re: 1500 Mercury Blue Band Cracked Block Watter Passage

There are some 115s with the fingerports in the blocks out there, I used to have serial number group, the 115s just had 115 pistons and could not use the poet and the 150s used the finger ported piston also use the 150 reed cages as they have a extra petal in them. You can probably get the good block numbers from the scream and fly site.