Oh I forgot its a 18 foot jetboat with thru-transom exhaust and a medium built 455 olds.
I changed my intake manifold. I changed my intake gasket,waterpump plate gasket,timing cover gasket and I still have water in my oil. I ran it tuesday to test it and I had no water in my oil for an hour. after that it had little water in it. I didnt hear any rod knocks or bearing spins. What should I do???? My dad is tearing it down this winter and redoing the whole enging. A couple of guys told me they always had a little water in thier oil and ran thier engines for a couple of years without problems. coul someone please help me out I stayed up straight for 2 days to fix it and I'm back to square one. I gat new interior a new floor and a new place diverter and I am scared to blow it up. I just want to enjoy it for only 2 months more. What should I do????????????
Oh I forgot its a 18 foot jetboat with thru-transom exhaust and a medium built 455 olds.
396 run a compresion test may show a bad head gasket. Do you know what the water preasure in the block is? If the water preasure is real high
you will never keep a gasket seal.
396, I believe WS meant a "leak down" test. When you do the test and apply pressure air to the cyl (tdc compression...every cyl), you need to pull a coolant hose and looks for bubbles or listen for air. If the leak is big you'll easily be able to find it, if it is small it will not be as apparent.
If you have other problems they will show up here also. Air coming through Exh = bad seal on the exh valve, air through carb = bad seal on intake valve, air in crankcase = bad head gasket.
Good luck, Mike
How much water is getting into the oil?
What kind of speeds are you getting? The reason is that a lot of speed can ram the water pickup, and overpressure the system. If you have a fast boat with a stock water pickup, put a pressure gave on the suction side, and see where it is going.
Do you have an oil cooler?
I will do a compression test tomorrow.
Not too much water is in the oil. I see it in the oil filler neck.
My speed is actually really good probably around 60 at wot.
No I dont have an oil cooler.
What do you mean by "a little water in the oil"? Does the oil level rise noticeably on the dipstick, or are you noticing a little water laying on the heads after you remove the valve covers or a little slime around the oil fill and on the underside of the valve covers. If the engine is not running at automotive temps it will have some traces of oil, if your headers are wet, necessitating more frequent oil changes than in an automotive application.
Do you have a shutoff valve on the inlet side on the water pickup (located between motor and pickup). If your engine temp is good you can try to shut the water supply off a little to decrease the possibility of over preasurizing the system. I would recommend doing a leak down over a compression test if possible. That way you can try and figure out where the leak is coming from if there is one.