you are right I could be wrong on this. The manifolds are always first to go out in a lot of cases. The only reason I said that is because I don't think you did not have this problem with water, Before the rebulid but I could be wrong. And If that is the case then maybe the manifolds are why you needed a rebulid in the frist place. I am just saying right now it is all guess work right now over the web and you need to look at everything that could go wrong even after a fresh rebulid job any thing can happen. Sorry I do not mean to scare you just help is all.:)

No worries, i can't be anymore scared than I already was....:eek:


When i first got this boat, and the breathers were hooked up according to mercruiser, other than having the short hose going to the arrester, and butted up to the eddie marine arrester, i was getting some of the same sort of gunk and snot from the breather line that was spurting out on different things. That could have been signs of things going south then, but i just got the boat, and didn't think anything of it. Hence I teed the lines, and put it up to the hose barb to be less messy. It's possible there was a problem then, or it could have been lack of oil temp too. Don't know. But, i do know the manifolds will be checked, riser gaskets will be rechecked, and riser flanges checked for warping. That's the first step the shop is going to take.

I have talked to the boat shop, and engine shop, two different places, same city. The engine shop i'm working with is Goodwin Competition. The main guy there doesn't think the exhaust is leaking water that i would actually burn when running, creating moisture in the breathers. He says, if it's that amount of water, it would start to hydro lock the motor. From the little bit of research i've done, it seems possible in my mind that the motor could be burning a small amount of water and then getting the breathing system restrictive with junk. The motor has never had any problems turning over or starting. Little bit of a ruff idle was apparent first start of the year, but that's about it. Any comments.

Well, i pulled the plugs out again tonight, and turned the motor over like the engine guy wanted. Water spray would come out of the middle two cylinders on the left side, looking at the engine from the front. Everything else seemed dry. Not alot of water, but noticeable, i could see water droplets on the top of those pistons as well.

Well, here's the latest. IMCO checked out my manifolds and said there are no problems with them or the risers. The marine shop and engine builder have spoken with the guys at IMCO, and IMCO is saying that the riser I'm currently using will not work with my cam. My engine is basically a 502 mpi, that has been brought up to HP 500 specs. The cam is a crane 226/236 .587 .610 112 hyd. roller. I have silent choice exhuast that is IMCO as well. Right now i have the 02-6108 risers for silent choice. http://imcomarine.com/ca_store/index...cPath=16_57_72
Mr. IMCO is saying that this particular riser would cause reversion with my engine setup. IMCO says i need to either run the 02-6096 (meaning no silent choice) or the 02-6109. I don't think i will have room under my hatch to go with any larger riser. My engine builer is not in total agreement, and says the cam is pretty mild. He is still theorizing himself. They are going to do pressure tests on the motor tomorrow. I'm not sure what to think at this point.

Keep on testing the engine just to be safe, But I will say the imco guys really know their stuff by trial and eare. They do LOTS of testing and inpesecting after almost if not every time they run a boat any where they go. They do put in 110% into all their stuff and work they do to try to get it right. Thay are one big :circle: that know what they are doing when it comes to boating.:):boat:

my experience is most of the time, everyone is right! the engine builder is right and is 100% sure he is not the cause of the problem. Then if there is a problem, the machine shop (if not done by the engine builder himself) says he did it right, it's the engine builder's fault, the your example, the exhaust guy that says something that may put the engine builder in problem... it's never someone's fault, but there is often a problem that needs to be solved...

Since 4 or 5 years, I go to a one stop shop, that does everything in house, EVEN drop the engine in and hook it up so if there is something not working, IT'S HIS FAULT!!!!

Early HP500's had reversion problems with a cam smaller than yours and with risers of a similar length.

So what's the solution if i don't have the hatch room to put on 3 inch risers? Eliminate the silent choice and go with mufflers straight out the back?

Hate to say it. All of this stuff costs so much. Rule out leaks or cracks everywhere else first.