Need help with Mercruiser 140 Exhaust manifold leak and replacement!

2101394sam

Cadet
Joined
May 17, 2012
Messages
26
Hey guys. I looked around for a while and couldn't find any other posts that could help me so hopefully I can get some info for my current situation. I just installed a new lower shift cable on my mercruiser 140 and I want to run through some of the more important parts before I take her out on the water for the first time.

Anyway.. I noticed I have an exhaust manifold leak. I had cleaned up the carb and changed fluids after sitting. and once I had it running I heard a little hissing sound in timing with the motor. I looked under the big exhaust tube thing and whala. there is a dark blackish spot from the carbon that was on the side of the block. I believe it was spraying out against the block from the gasket leak. So I am going to remove the carb(unless I don't have to) and replace the gasket and clean out that portion of the water/exhaust tube thing. I'm going to buy this kit for the job

http://www.ebay.com/itm/Mercruiser-...ar&hash=item35be97f81c&vxp=mtr#ht_1918wt_1396

Are there any helpful tips for this job? Will this kit be all I need? and I'm confused. I'm 19 and I'm a do it myselfer kinda guy loll. But I'm just wondering Doesn't water flow through this water/exhaust tube and mix together and then spit out from the propeller? when my engine is running why doesn't water also spit from this leak? How does this system work?

Also I was looking into blowing out the crap in the engine water jackets. how do I do this? or how do I perform an engine flush? to blast out any rust or debris that may be built up in there. I'm wondering this because I removed one of the hoses at the front of the engine going into the thermostat and I was kinda worried because the inside of the metal was rusted on the inside. it is still solid and sturdy. but there was still rust on the inside. I replaced both hoses on the front but I can't help what is inside the exhaust manifold/water mixerthing!?1<-- or whatever the hell its called. Hope I can get some info from one of you boat pro's!
 

2101394sam

Cadet
Joined
May 17, 2012
Messages
26
Re: Need help with Mercruiser 140 Exhaust manifold leak and replacement!

Found the solution. After pulling the manifold I found that the little tube that goes up to the choke through the exhaust pipe had moved upwards and exposed a hole at the bottom of the manifold
 
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