need help tearing down powerhead

awthacker · #1 01-15-2012, 12:02 PM

Because my motor seized up, I'm trying to disassemble it to find out where the corrosion was and how it got in. I have pulled my cylinder heads and the carbs and am now trying to pull the front section of the block off of the powerhead. Is there any secret to it? There is a shifting rod blocking me a bit. It's circled and pointed to in the pictures. Am I gonna have to drop the lower unit? I'm trying to leave as much intact as possible because it is already going to be a huge challenge for me to get this thing back together (if it ever happens).

THEFERMANATOR · #2 01-15-2012, 01:48 PM

The powerhead must come off to go any furthur. there are mounting studs and bolts that go in underneath there that also hold that front on as well as screws inside of the lower and upper bearing retainer. Pull the case half bolts back down and pull the powerhead.

awthacker · #3 01-17-2012, 01:34 PM

Thanks Ferm. Two of the six 1/2" bolts are locked up pretty good, so I soaked them and will try to rock them out tonight. Think I'll need a shop crane to lift this thing? What kinda weight should I expect to be lifting?

awthacker · #4 01-17-2012, 09:31 PM

Got all the bolts out today. Think I'll drag the boat to work and use the forklift to hoist it, then lower it into the truck bed.

THEFERMANATOR · #5 01-17-2012, 11:26 PM

I wouldn't reccomend trying to lift it off by hand unless you ate your wheeties and then some.

awthacker · #6 01-19-2012, 02:33 PM

Even with this cherry picker, I can't raise the powerhead. Not sure if these pics show it clearly, but something's holding it in the front and it seems to be the shaft. When I lift, the entire engine tilts. Bouncing on the lower unit doesn't seem to help.

awthacker · #7 01-20-2012, 01:29 PM

Dropping the lower unit was the key. It was the shift rod that was keeping the block from seperating, and it came out with the foot. Finally got into the crankshaft and it does have significant corrosion on it. Based on some previous posts and replies, this was the point I needed to reach to determine what the problem is and what to do next with the engine.

Based on the corroded cylinders and crankshaft, is it time to repower?
Is replacing just the powerhead an option?
How do I know if my lower unit is in good condition?

Orlando · #8 01-20-2012, 01:46 PM

im no expert, but i would pull the cylinder heads and check the cylinder walls see what condition everything else is in first, before deciding to rebuild/replace/repower. i would check condition of lower unit. also depends how much you are wanting to spend. rebuild kits for the power head are available on ebay for the do it yourselfer, so are rebuilt powerheads, but the other guys on here can probably give much better suggestions.

THEFERMANATOR · #9 01-20-2012, 02:27 PM

Get it fully torn down and inspect it and see where your at first. Right now you can't see any of the journals on the crank. Also you need to figure out how the saltwater got into the crankcase.

awthacker · #10 01-20-2012, 09:05 PM

Cylinder heads are off. I think the water got in around the bottom cylinder on the starboard side and/or the thermostat on the same side. There was pitting on the heads, but not on the block. My hope would be to clean and rebuild, I guess have the cylinder heads machined until smooth.

In the previous thread on this subject, someone suggested that if the crankshaft was rusted, I would be better off with a new powerhead.

http://www.wellcraftv20.com/communit...t=16993&page=3

Now that the lower unit is off, I'll try again to lift the powerhead tomorrow.