Stuck Power Head Merc V-150

[AndyL]

Re: Stuck Power Head Merc V-150

Working on the thread of super cooling you can buy aerosols in UK that freeze pipes for plumbing repairs so that you do not have to drain down the system, Also Chewing gum remover is a freezing agent that solidifies gum so that it can be "cracked" off carpet.<br />I am not sure how successful it would be as the temperature drop/coefficient of contraction at the temps concerned would be pretty small against the holding power of the corrosive agents.<br />Still hoping for your suceess.<br />Andy

 

[chrysleroutboard]

Re: Stuck Power Head Merc V-150

In theory both methods will work but metal has more expansion ratio than contraction ratio. Therefore it works much better with heating than freezing. Practically heating is easy to achieve than freezing.

 

[RICKRICK1]

Re: Stuck Power Head Merc V-150

Outrage-- not sure if any one has mentioned it but if you are going to try and heat the stud only, get some thick card board the compressed kind and cut a hole that will fit over the stud. then all you need do is saturate the cardboard prior to heating if it drys up just add water. the card board will burn before your alloy melts. this also deflects heat away from the alloy.<br /><br />just my .02

 

[Tinkerer]

Re: Stuck Power Head Merc V-150

Outrage<br /><br />Heating then cooling probably not a good idea. The greater the difference between the high and low temps and the more sudden the drop in temp, the more likely you are to fracture or damage metal. e.g. putting cold water into a car cooling system after you've cooked it and lost coolant will often crack the head.

 

[Outrage-19]

Re: Stuck Power Head Merc V-150

What about trying to freeze the stud with AndyL’s pipe freezer using the saturated cardboard to shield the alloy. Then heating the alloy with the cardboard in place to keep the stud from getting hot?

 

[Tinkerer]

Re: Stuck Power Head Merc V-150

Outrage<br /><br />Physics ain't my strong point, but if you freeze the stud it should contract away from the alloy housing. If you heat the alloy, will the hole expand towards the stud or contract away from it? If it goes towards the stud, it just cancels out what you're trying to do.<br /><br />Over to anyone who understands this better than I do.

 

[jim dozier]

Re: Stuck Power Head Merc V-150

Remember it is the differential expansion/contraction of different metals closer or further to the temp change that counts towards breaking the bonds of corrosion between the 2 metals. Metals expand in three dimensions when you heat them and not necessarily equally in the 3 directions when you're lookin at a long bolt in a drilled out hole. What you're looking for is movement. Even if it got tighter when you heated it that would be OK because when it cooled back down it would be less tight and the movement might have broken some of the bonding from the corrosion. Heat is simply easier to apply than cold. You might try heating the bolt and then spraying it with water or WD40 or penetrating oil to cool it down fast. Ultimately I think there's going to be a lot of banging and cussing to get this sucker moving.

 

[Outrage-19]

Re: Stuck Power Head Merc V-150

Ok so just keep heating, banging, cursing, maybe a little black magic like swing a cat in a burlap sack over my head three times on a full moon, bring in the pope in to bless it, and on the second Tuesday of next week it might come loose. Seriously thanks a lot for all the help. I’ll keep at it I can’t afford to replace it. This Sunday is my wife’s birthday so I’ll only have a couple of hours on Saturday to work on it. I’ll let you know the out come on Monday.

 

[jim dozier]

Re: Stuck Power Head Merc V-150

What more could your wife want on her birthday than to watch you curse and bang on your disassembled OB? It doesn't get any better than that.

 

[macojoe]

Re: Stuck Power Head Merc V-150

Hi there I am not a macanhic but I have had problems like this before. First Heat works great. The trick is to get it cherry hot and the wait till it completely cools!! Then you can try a impact wrench. Also I don't no if this is your problem but on my Yamaha the studs are tapered. So they canot go thur the holes in the casing!! You need to unscrew the studs to get them out or drill, cut them so the studs will pull thur.<br />Good Luck

 

[chumbucket]

Re: Stuck Power Head Merc V-150

You can have the birthday party out at the powerhead. Everybody can pull up on PH.Or give everybody a hammer.

 

[Outrage-19]

Re: Stuck Power Head Merc V-150

Will going out to the boat on Saturday went over like a lead balloon so nothing got done this weekend. If everyone who showed up at the party on Sunday went out to the boat we definitely had enough testosterone and beer that it would have come off one-way or another. As usual the guys were all out at the bonfire drinking beer and the women were all in the house gabbing. Not a total loss though one of my wife’s friends husband has an oxy acetylene set and he is willing to bring it over to heat this thing up. Keep you posted.

 

[Hooty]

Re: Stuck Power Head Merc V-150

Now you're "cookin'". Don' over-het anything. Use a wet rag on the aluminum.<br /><br />c/6<br /><br />Hooty

 

[AndyL]

Re: Stuck Power Head Merc V-150

Powerhead will feel acetylene heat you say. May the force be with you.<br />Yoda.

 

[Outrage-19]

Re: Stuck Power Head Merc V-150

bump

 

[Outrage 19]

Re: Stuck Power Head Merc V-150

bump

 

[Outrage 19]

Re: Stuck Power Head Merc V-150

I tell ya I’m not going to make it in the water for Memorial Day Weekend. This Saturday we have a wedding to go to, and Sunday is Mother’s Day. Like Jimd said “Its a bummer when life gets in the way of your boating”. Maybe I’ll catch the second half of Rockfish season.

 

[jim dozier]

Re: Stuck Power Head Merc V-150

Dang, I've been watchin and I thought you'd have that sucker off by now, or at least have a "new anchor"!

 

[AndyL]

Re: Stuck Power Head Merc V-150

Take a day off and really go for it.... I am losing sleep for you.

 

[Outrage 19]

Re: Stuck Power Head Merc V-150

I might just have to do that Andy. I’m getting antsy myself. My dad gave the boat to me last year in exchange for some work I did on his new house. It had been sitting for about two years. I got the engine started but it wouldn’t idle without working the enricher so I rebuilt the carbs. I ran it for about 2 hours after the rebuild and it started to slow down, and seized up. I let it cool down and started it back up hoping to limp back to the dock but in about 15 minutes it seized up again. This time when I got it started there was something knocking inside it. A compression test showed no compression in # 6 cylinder but all other cylinders were 125 lbs. I pulled the head and found the # 6 piston was chewed up to the point where the rings had failed. The cylinder walls were not scratched or scored so I decided to rebuild, hence the need to pull the power head. I have already bought the replacement piston and gasket set so once I have the power head off it should not take that long to rebuild and get running. After a couple of shake down cruses it’s off to the Chesapeake Bay for some rockfish. Well that’s the plan lets hope the stuck power head is the only snag I run into. Any way thanks to everyone for all the help and support we’ll get this thing off, rebuilt, back on, and running before long.