Go Back   Maxum Boat Owners Club - Forum > Maxum General > Engines
Click Here to Login
Register FAQ Community Calendar Today's Posts Log in

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 04-29-2009, 11:52 PM   #1
Ensign
 
Join Date: Apr 2009
Posts: 1
Default Salt water getting into engine

Our boat is a 2001 3700SCR. Again I have a major engine problem with salt water from the exhaust cooling system getting in the engine. Work has been done by authorized Mercruiser mechanic who says may be a design problem. Risers and all components in excellent shape. Results in exhaust valve sticking, push rod bending, etc., etc. Ever hear of this? Getting very, very expensive.
__________________

tomshideler is offline   Reply With Quote
Old 04-30-2009, 03:11 AM   #2
Admiral

 
seapuppy's Avatar
 
Join Date: Nov 2005
Location: Everett Wa
Posts: 4,681
Default Re: Salt water getting into engine

yep...this happens from time to time..usually a riser leaking and sucking into the exhaust...


SP irate:
__________________

__________________
Don't compare your life to others. You have no idea what their journey is all about.
------------------------
SSN683 Association member
Par Excellence
------------------------------
2008 Bayliner 340 - "Wild Whim"
--------------------------------------
I live in my own little world....but it's okay-they know me here!!!

Avid practitioner of the martial art: KLIK-PAO.
Tap-Rack-Bang

Anyone that sez "Size doesn't matter" has never owned a boat!
seapuppy is offline   Reply With Quote
Old 04-30-2009, 05:52 AM   #3
Lt. Commander
 
Join Date: Feb 2008
Location: Notts UK
Posts: 186
Default Re: Salt water getting into engine

Its got to be a bad riser or manifold unless its down to head gaskets unless its coming back up the exhausts when you shut off the power but the little valves in the downpipes should stop that happening

But surly if work has been done before and its happened again, it wasn't fixed properly in the first place do you have any comeback with the boat yard?

I must say the standard manifolds and risers are a very poor design. I really didn't want to fit even new ones so I designed some new ones and had them made out of stainless.
__________________
Gaz
Gazjen is offline   Reply With Quote
Old 07-09-2009, 06:25 PM   #4
Moderator

 
shrew's Avatar
 
Join Date: Apr 2008
Posts: 5,682
Default Re: Salt water getting into engine

I know this is an old post, but it's worth posting for others. What Gazgen is describin sounds like 'Reversion', which can dump water back into the engine through the exhaust valve's, even when the manifolds and risers appear structurally sound. The actual term is 'Resonance Reversion'.

here is a good doc which describes this process:

http://www.michel-christen.com/ExhaustElbows.pdf

I've seen this happen with aftermarket manifolds which internally aren't designed quite the same internally as the OEM parts, such as Genuine Mercruser parts. There should be a small internal lip which should prevent reversion from allowing water to backlow into the exhaust manifolds. I had two friends who experienced this shortly after replacing Mercruiser Mainfolds and Risers with Osco manifolds and risers because (supposedly) the Osco manifolds and risers didn't have this lip or the lip isn't placed and /or sized correctly to completely prevent revesion. I've heard tell of a situation where the riser and elbow were not sized tall enough to prevent reversion as well. the doc above discusses this in detail and is worth reading by anyone who uses exhaust manifolds and risers.

This is just one man's opinion (FWIW) so for those who use and swear by aftermarket or Osco specifically may have a different opinion.
shrew is offline   Reply With Quote
Old 03-17-2014, 05:51 PM   #5
Ensign
 
Join Date: Mar 2014
Posts: 4
Default

I am in the process of remanufacturing the 8.2l engines on my 98 3700scr due to this reversion problem. My mechanic is suggesting 6 inch spacers instead of 3, along with turbulators and resonators to prevent water ingestion. Seems like a design flaw. Anyone else ?
khendra is offline   Reply With Quote
Old 03-17-2014, 10:06 PM   #6
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 10,606
Default

khendra welcome aboard. WOW you sure dug up an old thread.

Gonna have to see i others with the similar setup have anything to say here.
__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Old 03-18-2014, 02:32 PM   #7
Moderator

 
shrew's Avatar
 
Join Date: Apr 2008
Posts: 5,682
Default

3" risers seems too short. I thought 6" was standard.
__________________

shrew is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
2001 2700 SCR tune up cgheli Maxum Maintenance 4 09-24-2009 01:02 AM
electric head not getting power dsack Maxum Maintenance 3 09-11-2009 05:18 PM
Force engine 85 hp NH badboy1166 Engines 1 08-28-2009 05:40 PM
convertible top windows craigblue Maxum Owners General Discussions 2 06-23-2008 08:21 PM
What engine should I buy? hybris1 Engines 4 05-07-2008 03:03 AM

Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 06:46 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.