Re: Progress and Compression..Please help guys!!!
I've posted this very message over on the bigweek merc inlines forum also - <br /><br />Hello guys,<br /><br />Pretty gutted as I type this as I feel my my powerhead may be going in the <br />bin.<br /><br />To explain what has been done....This is a long haul, your patience <br />appreciated.<br /><br />I removed my powerhead as there was water coming out of the base of the <br />exhaust manifold cover plates at the bottom. There was also water coming <br />from around the plug holes. I ran a compression test and discovered 2 <br />cylinders were down dramatically.<br /><br />I managed to find another powerhead with compression results as follows.<br /><br />1 - 140psi<br />2 - 140psi<br />3 - 140psi<br />4 - 140psi<br />5 - 135psi<br />6 - 140psi<br /><br />However the crankcase cover plate was cracked and the starter motor mount <br />was broken off.<br /><br />I know it is a bit hit and miss but with the advice and help from folks on <br />iboats I swapped the crankcase covers to find that that the difference was <br />nearly nothing and in order to get an absolutely perfect fit I had to remove <br />one of the guide dowels and very carefully allow the reed blocks guide me <br />into place.<br /><br />All sealed up and rocking!<br /><br />Next I removed the exhaust manifold cover plate as it was missing a bolt in <br />the centre and I could not get another bolt to thread into it. When I <br />removed the plate I discovered that part of the alloy where the bolt threads <br />into was broken away. As an attempted solution to this I placed a broken <br />stainless steel bolt head in the cover plate and filled over the recess in <br />the plate with jb weld to stop any water coming out.<br /><br />I then used the correct gasket sealer kindly supplied by Wayne on all the <br />now scrupulously clean mating surfaces with new gaskets and torqued to <br />specification.(Having to now ignore the missing bolt filled with jb weld)<br /><br />Replaced the gasket on the spark plug side water cover and all the gaskets <br />on the fuel pump side of the head.<br /><br />Rebuilt all carbs to secification replacing everything including floats.<br /><br />Rebuilt the fuel pumps.<br /><br />Mounted the powerhead.<br /><br />Connected everything back following the instructions in the Mercury manual.<br /><br />At this point in time my lower unit is removed as there is water getting in <br />due the top driveshaft seal leaking so I connected a hose to the water pick <br />up pipe and run water through until water is pouring from the base of the <br />leg and I have a consistent pee stream. I notice at this point water leaking <br />slightly from some of the bolts in the exhaust cover plate however, not a <br />major amount...none the less dissapointing.<br /><br />Prime up the bulb and it goes hard as expected, I give it a birl on the <br />starter and after a little bit of choke and some throttle it kicks and runs, <br />with lots of vibration through the boat as though its not running on all <br />six. Then swifty cuts out and seems to kick back the way.<br /><br />I run it again, with absolutely no chance of it idling.... Take it to about <br />2k rpm and then it just fouls up and cuts out again...<br /><br />This is the bit that annoys me..... I remove the plugs and one by one they <br />are coated in a coffee like substance and what looks to be beads of water...<br /><br />Where I go from now will be with your guidance folks...<br /><br />Many Thanks...<br /><br /><br />A sincerely gutted Stan :-(
