Go Back  The Hull Truth - Boating and Fishing Forum > BOATING FORUMS > Marine Electronics Forum
Reload this Page >

Heading sensor and Bilge pump interference

Notices

Heading sensor and Bilge pump interference

Old 07-13-2019, 09:24 AM
  #1  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: May 2006
Location:
Posts: 455
Default Heading sensor and Bilge pump interference

On a friendís 25í Parker Outboard the "Precision 9" heading-sensor could never be calibrated to have the AP function properly, a long standing issue. By using a small handheld compass to find a possible magnetic interference it pointed to the small Attwood 500 GPH permanent magnet bilge pump in close proximity. After removing the pump the calibration was successful and the AP works now perfect.

The Precision 9 and the pump are in an ideal location individuality but not while located in the same area. The pump is in the lowest place in the cabin bilge and the Precision 9 is mounted on the bulkhead separating the cabin from the cockpit above the pump.

Best solution, move the Precision 9 but it's hard to find a good spot, itís all a compromise. Someone on the dock mentioned a brushless pump so I went to west marine with my handheld compass and found the Attwood definitely produced a stronger magnetic field then some other pumps but they all showed some interference.

Does anyone know of a small bilge pump that may work in this area?

Was looking at a Rule-Mate 500 model 19298413 that looked promising, but maybe someone has experience with better pumps in that respect.

Abbor, if you are reading this, in a prior post you told the poster that you had a post on heading sensor but I couldn't find it. If you could point me to it I would appreciate it.
BajaFeeling is offline  
Old 07-13-2019, 09:46 AM
  #2  
Senior Member
 
Join Date: Oct 2018
Location: Puerto Rico
Posts: 134
Default

The bilge pump is far more important than the flux gate sensor. Move it
jwelk is offline  
Old 07-13-2019, 11:08 AM
  #3  
Senior Member
 
Join Date: Mar 2015
Posts: 416
Default

Do they make a diaphragm pump that could do 500gph? If so you could mount the pump away and a suction hose to the low point.
ole_blue is offline  
Old 07-13-2019, 12:14 PM
  #4  
Senior MemberCaptains Club Member
 
Join Date: Feb 2003
Location: M.Vineyard, MA
Posts: 14,083
Default

It's more expensive, but switching to a HS-60 GPS antenna//compass- heading sensor would solve that problem as it does not determine heading by detecting magnetic fields, and is unaffected by them and ferrous objects.
https://www.simrad-yachting.com/simr...0-gps-compass/ ( A quick search will find them for $100s less.)

(And FWIW, .... IMO, a 500 GPH bilge pump in that area is way too small on that boat even assuming you have an add'l one by the transom And due to discharge head height actual output would be considerably less. )
TTaxi is offline  
Old 07-13-2019, 01:04 PM
  #5  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: May 2006
Location:
Posts: 455
Default

TTaxi , I realize 500 GPH isn't much they describe it as a nuisance pump to keep the bilge in front dry, wouldn't do much if there is leek of any proportion . The aft pump is more substantial. Factory installed minimum.
BajaFeeling is offline  
Old 07-14-2019, 10:01 AM
  #6  
Senior MemberCaptains Club Member
Thread Starter
 
Join Date: May 2006
Location:
Posts: 455
Default

Thank you for all your constructive replies, all good options. The HS-60 GPS would certainly be a great way for a new install. At this time now that the P9 is actually working for the first time I would hate to recommend throwing that $600.- unit out and spending $900.- to replace it but it would solve the issue once and for all if it actually works as well as described.
We probably will move the P9 under the floor in the cockpit, there is a hatch and a bulkhead far enough away from the Pump.
No one addressed the magnetic affect between a brushless pump vs a permanent magnet pump like the Attwood. On my boat I have the KVH Autocomp 100 and a Rule 750 in the same cabin area without an issue, the Autocomp may not be as sensitive as the P9 and I donít have an AP. Donít know?

BajaFeeling 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 Off
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread