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awthacker
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
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
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
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
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
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.

Skools Out
01-19-2012, 03:16 PM
not good the last pics show the powerhead adapter is coming off with the powerhead and it looks to be bad. by the way why did you tear down the motor first? you may have had a locked up lower unit. just a thought, always remove the lower unit first.

awthacker
01-19-2012, 04:00 PM
Thanks Todd, but not very helpful at this point. What is the powerhead adapter? Should I soak the shaft with anti-seize or do I just need to use more force?

phatdaddy
01-19-2012, 10:09 PM
might want to run a couple of the bolts back down and remove the lower unit first. the drive shaft might be frozen to the crank. have you pulled the foot lately?

awthacker
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
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
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
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/community/showthread.php?t=16993&page=3

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

awthacker
01-23-2012, 02:40 PM
Still can't lift the powerhead. I do see two 3/4" bolts run into some rubber seats in the midsection from the mounting bracket. Do these need to come out, too?

phatdaddy
01-23-2012, 05:03 PM
i think those are the mounts for the transom bracket to the mid section. they run horizonal, i think all the bolt you need to remove power head are vertical.

hang on though, wiser heads will come along.

awthacker
01-23-2012, 06:56 PM
I jack up the powerhead and it seperates nearly 1/2", but won't lift off. The whole boat lifted off the trailer.

I don't see anything other than the 3/4" bolts, and I can't get them out.