Re: should i clean it up are not ????
I am kind of suprized you had to remove the powerhead to get at the impeller,Gerke. I've never had the "pleasure" of werkin on one of those,but it sounds like I'll pass
<br /><br />But anyway, now would be a great time to inspect the lower unit for leaks,and gear lube condition.<br /><br />That chalk is iether corrosion (aluminum oxide), or crystalized salt, and should be carefully removed. If the exaust port and manifold are full of this stuff, you can bet the entire cooling system is, also. Remove the head,and get as much of it out as you can,without letting any of it loose in the engine's water jacket. I've heard of marinas using an acid flush for this stuff,that works great. I think it's the same acid used in radiator shops,so you may be able to have it cooked out there too (re-assembled,and a pump hooked up to the intake and circulated thru the water jacket).<br />The black soot is carbon. This is normal for all 2cycle engines, but can build up to engine-ruining levels. It can completely plug exaust ports, get behind the ring lands, causing the rings to swell-up in the jug, wearing your engine out way before it's time,and loosing compression in the process..<br />It can foul plugs, but then, the plugs only last about 80hours on them.<br />Frequent decarbing (about every 60-80 hours of operation,and more frequently,if you idle a bunch),will keep it under control. There are fuel additives, like Seafoam, and there are spray type treatments, like Powertune,and Valv-Tect. I personally like the spray types, as additives tend to make my Force and Merc engines run lousey while the stuff is in there.<br />Be prepared for an embarassing amount of smoke durring,and for about 20minutes after decarbing.<br />Hope this helps ya.
