Pulling powerhead

[Rayson1971]

I have an 87 200 BM and pulling the powerhead. Hasn't been off for a long long time. Seams to be frozen on. Any ideas? Rosebud torch?

 

[Crazyhippy]

Triple check you got ALL of the nuts off...
I have had good luck with a bit of time, penetrating oil, vibration and heat.

Spin 2-3 nuts back onto the threads, but not tight. Use your hoist to put tension on everything. Not picking the whole boat up, but enough to know the load on the studs is going up instead of gravity. Lots of penetrsting oil.let it sit overnight. That will get freshwater motors free most of the time.

An air hammer vibrates the studs and help break the corrosion free too. Using heat, i do a small tip, and just heat the stud, then spray with penetrating oil for a nice smokescreen. The heat pulls the oil up the stud nicely.

Lather, rinse and repeat as needed.

 

[sonicss31]

Looks like you missed 2. One on each side.

 

[Rayson1971]

Looks like you missed 2. One on each side.

View attachment 1432367

Where. I pulled every one i could see. The 2 in front the powerhead needs to be loose to get the nuts off. I loosened 5 on each side.

 

[Flying_Lavey]

Where. I pulled every one i could see. The 2 in front the powerhead needs to be loose to get the nuts off. I loosened 5 on each side.

There are 3 or 4 seams there. I suggest working your way down from the top seam first. I believe there are 1 or 2 nuts/bolts inside that isnt accessible until the layer above is removed. I am going off 15 year old memory though.

 

[HST4ME]

There is ten nuts total. The front two and the back four you can get a pry bar under and help it along

 

[Rayson1971]

Got the powerhead off. I have a lower unit shaft cut and mounted on a cart. Will it be ok to drop the powerhead on the shaft start disassembly. Or is there a better way to mount ?

 

[stingray11]

Rolling engine stand,just find the right bolts. Then you can spin it to disassemble it.

 

[lbhsbz]

I have some coupling nuts (long nuts) I keep on hand in most thread sizes....I cut them down to just tall enough to fit between the ends of the studs (on the rear studs) and the casting below it, and screw them on....then stick a piece of scrap metal in there and unscrew the nuts against your piece of scrap to jack the powerhead up from the exhaust adapter. Once it starts to break free...it'll all let go.

 

[Rayson1971]

Completely disassembled power head and

looks like 2 and 6 have some issues. I read the cylinder walls are chrome and can't be honed or bored. True. What's next?

 

[zhandfull]

Following! Would love to pick up an old 200 BM and bring it back to life.

Assuming the block is going to need some sleeves if they can’t be bored or honed.

 

[Rayson1971]

What's the best way to clean cylinder walls of aluminum from pistons to see how bad they are? I read toilet bowl cleaner that has murratic acid in it and a still bristle brush.

 

[n2otoofast4u]

Those cylinders look beyond muriatic acid fixable.

@HST4ME would know if you can have those re-plated or not.

 

[HST4ME]

It's not worth it money wise. Sleeve it or buy a 2.5.

That one is pretty well smeared and even with muriatic acid your going to be at that for awhile

 

[sonicss31]

2 and 6 need to be sleeved. Yes you can run with mix of steel and chrome cylinders. Just remember that different rings are needed for chrome vs steel.

 

[HST4ME]

Following! Would love to pick up an old 200 BM and bring it back to life.

Assuming the block is going to need some sleeves if they can’t be bored or honed.

A 2.5 is much more efficient.

 

[Rayson1971]

So the next question? Are the parts worth anything? Everything minus block.

 

[HST4ME]

I have a buddy that has a good block I think

 

[Rayson1971]

So let's say that's the way I go. Whats to going price for block and price for rebuild kit.?

 

[zhandfull]

A 2.5 is much more efficient.

So what pops up on marketplace? A wounded 200 BM. Yep, so I bought it. Figured I was good even if just for parts. Also had a nice cowl. #2 cylinder was sleeved in 2021 by Q&E out of Anaheim. Then rebuilt by owner. Said he only had a couple hours on it before having issues with #2 again. He ended up buying a used late model Merc instead of going down the rabbit hole again.

Quick inspection when I got home. Looks like a light bore and a new piston might be all that’s needed.

Fyi for OP:
Paperwork from Q&E showed a sleeve install at $200 and $50 for the bore plus some small misc. charges.

Previous owner said he was into rebuild approximately $2,400. Assuming that included sleeve work. He also mentioned new rod bolts, gaskets, piston, and rings.

 

[Rayson1971]

So I'm gonna box everything up and shelve it till I figure out if I want to fix at a later date. What's the best way to store the crank? Are the grooves in this area where my finger is normal?