higler
Well-Known Member
I Put a post on here a while back when I had an experience with sump pressure dumping the oil out from the sump pump and then losing oil pressure on refill and retrying to run it again. I am grateful for all the input I got from forumites who gave me a lot of information that was useful and were just as I was, almost there, but something just wouldnt add up. As the engine had only run for 65 hours some things dont spring to mind straight away, and that was the case in this scenario. After stripping everything down and checking and measuring all the mechanical parts I eventually decided to strip the breather valve in the rocker cover--I'd had people telling me that could have been stuck and would cause the pressure, but i'd already checked to see if it were free and it was, but once I checked it out and saw how it worked, it then led me to the air intake on the inlet manifold. As it was an angled fin type arrangement with a plate bolted to the front it wasnt possible to check it properly without dismantling. Once apart it was clear what had caused the pressure to build up, the fins were blocked with oil and particles and once the company who marinised the engine had sprayed it there was not enough air to supply the engines air intake. Someone must have guessed it wasnt quite right and had drilled 5 small holes in the front plate, but as it would have only given a hole of about 1/2 inch round it wasnt enough. Once the engine revs built up the inlet manifold was sucking like mad to get air and was sucking the valve closed in the rocker cover so it couldnt release the pressure from the sump, so it pushed the oil out of the sump pump the easiest route for it. I cleaned and respaced the fins and drilled many holes in the front plate and now shes up and running and hopefully without any more troubles. Oil pressure sender was faulty, renewed and all is well. I had bought this boat ashore which had lain in a yard for 4 years when the owner moved to spain he told me it had an oil leak what turned out to be from the sump gasket that was poking out, by what I now feel was due to sump pressure, he thought it was the front oil seal, but as this engine was new with second hand parts from his previous engine put on by the engineers --obviously they hadnt checked the units before they rebuilt it, It didnt occur to me as I thought it was all new so this trouble really threw me for a while. End result problem solved and A great big thanks to all who gave me the benefit of their knowledge and time, maybe this may be of assistance to someone in the future. THANKS AGAIN Norman.
