12.9HP with exhaust fumes out in the cowl

MickLovin

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Feb 18, 2013
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I am having exhaust fumes coming through between the power head and where it is bolted to, letting exhaust come into the cowl and choking the engine, the engine runs fine without the cowl but as soon as you put it on it suffocates it, the only gasket I can see on the parts list of where it might be leaking is the cylinder mounting gasket?? Is it possible to just seal where the power head is bolted down, I have tightened those bolts but it hasn't reduced it much and the bolts got about 1/2 to 1 turn.:confused:
 

Big Fish Billy

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Dec 31, 2009
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301
Re: 12.9HP with exhaust fumes out in the cowl

What year and make is the engine...sounds from a distance, like the gasket between the powerhead and lower unit is blown and needs to be replaced....like it did on mine......
 

oldboat1

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Re: 12.9HP with exhaust fumes out in the cowl

might pull the lower unit, grab a flashlight and look up under there. You could have an exhaust blockage in the leg -- favorite place for wasp and mouse nests. Can run a wire up into the exhaust ports in the leg (rear of the leg on yours, I think, just under the powerhead?) And of course while you have the leg off, you can also switch out the impeller.
 

MickLovin

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Re: 12.9HP with exhaust fumes out in the cowl

PICT0008.jpgThanks guys I will endeavour to look at this today and get back to you, it did have a corrosion crack on the side which I repaired with automotive bog, maybe the hole in it was an exhaust port which I may have blocked up causing the exhaust to try and come through the top., The gasket between the head the leg was loose and I was able to tighten it up, but I still had exhaust fumes, so I will check my repair, open it up and see if I can repair around the exhaust, may have to see if someone could do a weld. I do have a picture of it when I bought it with the corrosion spot, I will post it but I think it will be too small
$_14.JPG
 
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MickLovin

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Re: 12.9HP with exhaust fumes out in the cowl

Oh well worst comes to worse, I have a 6hp Chrysler I am buying from a 88 year old gentleman for $120. Would be just a shame after clening this one up to just let it sit in the garage, it has a great power head.
 

oldboat1

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Re: 12.9HP with exhaust fumes out in the cowl

parts is parts. a year from now, you might have a needs for a parts motor -- or inherit a lower unit that needs a good powerhead. If you end up storing it for "future use," prep it (fogging oil, drain carb, etc.) and cover it up. It's all good fun.
 

MickLovin

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Re: 12.9HP with exhaust fumes out in the cowl

PICT0001.jpgPICT0002.jpgCould you tell me if it is worth repairing the 12.9hp, my thoughts were to pull the power head off and replace the gasket, then put a plate over the hole and bogged it, am I kidding myself or is this a viable option, the only other way I can think of is getting someone to weld it but I would still have to replace the cylinder mounting gasket I believe. The oil in the picture is of concern too but I think it may be the fuel I am using as it is leftover mix I had.
 
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pnwboat

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Oct 8, 2007
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Re: 12.9HP with exhaust fumes out in the cowl

It's up to you as far as whether or not it's worth it. I'm usually drawn towards this type of challenge, but that's just me....LOL!

Instead of welding the hole, you might try this Super Alloy 1. I've used similar rods and it works pretty good on unknown aluminum alloys. Kind of pricey though, but if you can find a similar product cheaper, they're all pretty similar. The super 1 alloy has a very low melting point though.

Muggy Weld Super Alloy 1 Pot Metal Repair Kit

I wouldn't worry too much about the oil at this point. It looks like the normal exhaust residue. Get the other issues taken care of first.

You can also use some high temperature epoxy too to fill the hole in. That's probably the cheapest easiest way to fix the hole.
 
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