welding a midsection

fireman57

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Aug 24, 2004
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Hit a log a few weeks back with my '91 25 horse and cracke the midsection from ear to ear. Clean break from the exhaust holes almost around the midsection to the front. Hasn't broken through the front yet. JB weld won't hold it because of the vibration that it has. Has anyone had any luck welding them. A new one is 500 bucks. Welding it would have to be cheaper but if someone has tried it and it didn't hold then I don't want to waste the money.
 

tashasdaddy

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Re: welding a midsection

depending on what a qualified welder thought and what he charged, i would think it might be worth a try. that was a pretty good log. if it didn't work, you could still have a good lower unit and powerhead to either park out, or find another midsection.
 

fireman57

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Re: welding a midsection

It was a pretty good log at 25 mph. Didn't notice the crack until the next time out when I throttled up and felt a vibration. Next thing I know my starter came loose. Upon further inspection the vibration had sheared the front bolt on the starter and caused the two side bolts to come loose. I can set a stud in where the front bolt was and be fine but I have to get rid of the vibration so it will hold. I'm calling a buddy of mine tonight who is a crackerjack welder of all kinds and see what he thinks. I know that he is going to make me grind the JB weld off that I put on. Only fair.
 

tashasdaddy

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Re: welding a midsection

check the prop shaft for being bent. that may be the vibration.
 

fireman57

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Re: welding a midsection

Checked it and it is fine. No seals were harmed in the mishap. Just cracked the bejeebers out of the top.
 

R.Johnson

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Re: welding a midsection

The problem would be if it hit hard enough to crack, it is also going to be sprung out of parallel. The tolerance on the older exhaust housing was .005 out of parallel. A sprung housing can cause drive shaft breakage, or at least, undo bearing, and seal stress.
 

kenmyfam

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Aug 10, 2006
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Re: welding a midsection

It is often easier to weld the crack after drilling a small hole at either end of it to stop the spread and then welding a plate over it. A good welding expert will and should evaluate this at the initial inspection.
 

fireman57

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Re: welding a midsection

I do some welding but just the basics. This guy is a pro. Thanks for the opinions fellas and I'll see what he says.
 
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