Go Back  Offshoreonly.com > Technical > General Q & A
Crossover vs stock circulating pump >

Crossover vs stock circulating pump

Notices

Crossover vs stock circulating pump

Old 10-25-2011, 09:26 AM
  #11  
Registered
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default

You have something else going on.

For starters, I would not run the engines hard at 225* water temp. Thats pretty darn hot for a marine big block under tremendous load in a boat. Your oil temps must be very hot also if your water temps are that high.

You need a bypass hose, running from the crossover, to the thermostat housing. If you do not have this, you cannot run a thermostat. If you do have this, and the engine is still getting that hot, I would start looking for things like a lack of water flow. Such things as a clogged sea strainer, bad impeller, clogged oil cooler, collapsed hose, corroded water inlet at the transom if its a bravo, etc.

The reason your exhaust is probably steaming is its getting really hot, and the small amount of cold water they are getting is cooking in the manifolds and tails. I'd find the problem before you melt something.
MILD THUNDER is offline  
Old 10-25-2011, 07:20 PM
  #12  
Registered
 
Join Date: Oct 2005
Location: Millstadt, IL
Posts: 1,888
Received 18 Likes on 9 Posts
Default

There are a lot of myths about crossovers. Mine works perfect, to use a thermostat you must have the bypass hose. I used to use a standard thermostat and drilled two holes near the edge. I have more consistant temps now than with a water circulator. It also works better with a big oil cooler. This year I went with a high flow thermostat and drilled two holes in the center (looks like a cone) and they are even better now. I use a 160 degree thermostat and it runs about 160 deg at idle and about 150 running on plane. Good luck setting yours up, if you can post a pic or a link to one that would help.
jeffswav is offline  
Old 10-25-2011, 07:25 PM
  #13  
Registered
 
Join Date: Oct 2005
Location: Millstadt, IL
Posts: 1,888
Received 18 Likes on 9 Posts
Default

Originally Posted by MILD THUNDER
You have something else going on.

For starters, I would not run the engines hard at 225* water temp. Thats pretty darn hot for a marine big block under tremendous load in a boat. Your oil temps must be very hot also if your water temps are that high.

You need a bypass hose, running from the crossover, to the thermostat housing. If you do not have this, you cannot run a thermostat. If you do have this, and the engine is still getting that hot, I would start looking for things like a lack of water flow. Such things as a clogged sea strainer, bad impeller, clogged oil cooler, collapsed hose, corroded water inlet at the transom if its a bravo, etc.

The reason your exhaust is probably steaming is its getting really hot, and the small amount of cold water they are getting is cooking in the manifolds and tails. I'd find the problem before you melt something.
x2
jeffswav is offline  
Old 10-26-2011, 08:31 AM
  #14  
Registered
Thread Starter
 
Join Date: Aug 2006
Location: Gulf Shores, AL.
Posts: 87
Likes: 0
Received 0 Likes on 0 Posts
Default

Thanks to everyone for your responses and help with the heating problem. My Crossover has the intake side naturally and one hose leading directly up to the matching thermostat housing. Then there are two other larger ports, one for each exhaust manifold. I was using a 160 degree thermostat with 4 small holes drilled into the outer parameters of the stat itself, this did not seem to change anything. I noticed yesterday that the water when on the Mercury pin flushette I have always used and works fine, that the water sort of surges, it'll pick up and then fall off, like a pump that looses it's prime. Therefore I am pulling the impeller today and checking everything for restrictions and impeller damage. I will post what I find later today.
baja24outlaw is offline  
Old 10-26-2011, 09:27 AM
  #15  
Registered
Gold Member
 
Join Date: Dec 2004
Location: abell md
Posts: 545
Likes: 0
Received 1 Like on 1 Post
Default

Make sure u have the right thermostat gasket as well , if it has the square tip on the end your blocking water going to your risers
chuckels is offline  
Old 10-26-2011, 08:20 PM
  #16  
Registered
Thread Starter
 
Join Date: Aug 2006
Location: Gulf Shores, AL.
Posts: 87
Likes: 0
Received 0 Likes on 0 Posts
Smile

Problem solved!! after carefully checking everything, and replacing the impeller again, I found the cause, unbelievable but glad I found it. Restriction inside the oil cooler, some particles of plastic "not impeller material" got logged up and inside blocking the water flow. Cleaned it all out good and made damn sure it was clean, re-installed everything and now my good old 500 is running nice and very cool. About 120 degrees if that! Thanks to everyone whom responded and helped.
baja24outlaw is offline  
Old 10-27-2011, 04:32 PM
  #17  
Registered
 
Join Date: Oct 2005
Location: Millstadt, IL
Posts: 1,888
Received 18 Likes on 9 Posts
Default

Originally Posted by baja24outlaw
Problem solved!! after carefully checking everything, and replacing the impeller again, I found the cause, unbelievable but glad I found it. Restriction inside the oil cooler, some particles of plastic "not impeller material" got logged up and inside blocking the water flow. Cleaned it all out good and made damn sure it was clean, re-installed everything and now my good old 500 is running nice and very cool. About 120 degrees if that! Thanks to everyone whom responded and helped.
Glad you found the problem. Just noticed you are from Gulf Shores, went there last winter. Looked like a fun place to boat with the innercoastal waterway.
jeffswav is offline  

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 On
Pingbacks are On
Refbacks are On


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.