SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: riverjunky on March 20, 2011, 11:53:45 AM

Title: Need Advice
Post by: riverjunky on March 20, 2011, 11:53:45 AM
I have a jetboat with a 427 w/ bassett wet headers, I replaced cam, hydrolic lifters, new timing chain belt. What I am getting at is when I run water through my motor without it running it begins to pee out #3 exhaust hole of the wet header of the drivers side? I did replaced the head gasket yesterday and put it all back together and the same thing is still happening?  Is it possible that the aluminum intake manifold has a crack? Please help me to get this figured out, I have ran it by my many motorhead friends and I am at a loss.... :banghead:

***Thanks everyone for the advice, I found the problem with all of your help***
Title: Re: Need Advice
Post by: 75 fantasy on March 20, 2011, 12:53:21 PM
Welcome to SCJB  ;D
if I'm reading your symptom correctly i think water would be coming out of all 8 weep holes but in my experience if you run water through an engine and pipes without motor running it will fill up each header tube and cylinder with water and leak out of the exhaust holes. may i ask why are you running water without a running motor? are you checking for leaks? maybe close off the water to the pipes only and see if you get the same symptom but be careful if you run the motor with the water turned off to the pipes they will get hot and blue the chrome.
Title: Re: Need Advice
Post by: GT Jets on March 20, 2011, 02:18:29 PM
Never ever run water through the engine without it running....

As it stands you could have a couple of issues....A stuck basset valve (depends on how much water pressure you were pushing into the motor)...

Or the dump line you have is undersized (again depends on the water pressure utilized)...

My recommendation for troubleshooting would be to block off all water passages and put 15 to 20 pounds of air to it, it should hold for a while.... ;)

GT
Title: Re: Need Advice
Post by: riverjunky on March 20, 2011, 07:55:59 PM
I have a shut off valve to my wet bassett headers that will not allow water to get into my headers, I have had the shut off valve closed off, it still leaks through the #3? Whats up???

I have owned jetboats for 20 years and never had one water problem until now. Has anyone else had this problem before?

P.s. I never run water through my motor with out starting it. I was in the process of starting the motor when I noticed the problem....
Title: Re: Need Advice
Post by: propless on March 20, 2011, 08:17:30 PM
 Pull the headers off and plug the water lines to them.  Then run the water through the motor again just to be sure its coming out of the exhaust port.  If it is, pull that head and have it pressure checked. Sounds like you have a crack/hole in the exhaust port somewhere.  Sounds odd, but I had that problem with a set of ported heads that went a bit to far. The port wall got thin and developed a small hole that injected water into the port.
Title: Re: Need Advice
Post by: SS-201 on March 21, 2011, 01:35:05 AM
I have had the same problem and it is a small crack in the manifold. To test plug the exhaust end and put a little air pressure and a guage and you can see.
SMFPacks CMS 1.0.3 © 2026