Go Back  Offshoreonly.com > Technical > General Q & A
Ignition timing retards >

Ignition timing retards

Like Tree0Likes

Ignition timing retards

Reply

Old 07-13-2010, 02:03 PM
  #1
Registered
Thread Starter
 
Join Date: Oct 2006
Posts: 104
Exclamation Ignition timing retards

why does my ignition timing retard from 10 degrees to 0 when i rev the engine to appprox 2000 rpm,i have tried 3 different ignition modules and 2 distrbutors , it is a carburated 502 Mercruiser
markku4444 is offline  
Reply With Quote
Old 07-13-2010, 02:12 PM
  #2
Registered
 
Join Date: Apr 2010
My Boat: 94 Powerquest Legend 257
Posts: 547
Default

Originally Posted by markku4444 View Post
why does my ignition timing retard from 10 degrees to 0 when i rev the engine to appprox 2000 rpm,i have tried 3 different ignition modules and 2 distrbutors , it is a carburated 502 Mercruiser
If it's a thunderbolt V ignition, they have ignition retard function built in. It is controlled by the knock deterctor system. If that malfunctions or the connections between it and the ignition module are loose, it will pull timing.

Putting a thunderbolt V module on a IV system will cause the same thing.
apollard is offline  
Reply With Quote
Old 07-13-2010, 02:48 PM
  #3
Registered
Thread Starter
 
Join Date: Oct 2006
Posts: 104
Default

Originally Posted by apollard View Post
If it's a thunderbolt V ignition, they have ignition retard function built in. It is controlled by the knock deterctor system. If that malfunctions or the connections between it and the ignition module are loose, it will pull timing.

Putting a thunderbolt V module on a IV system will cause the same thing.
I dont think my engine got a knock detector,i have a thunderbolt IV, can i use a thunderbolt V if the engine does not have the knock sensor?
markku4444 is offline  
Reply With Quote
Old 07-13-2010, 03:25 PM
  #4
Registered
 
Join Date: Apr 2010
My Boat: 94 Powerquest Legend 257
Posts: 547
Default

Originally Posted by markku4444 View Post
I dont think my engine got a knock detector,i have a thunderbolt IV, can i use a thunderbolt V if the engine does not have the knock sensor?
No, they are not interchangeable, the V will retard all the time w/o the knock module present.
apollard is offline  
Reply With Quote
Old 07-13-2010, 04:08 PM
  #5
Registered
Thread Starter
 
Join Date: Oct 2006
Posts: 104
Default

Originally Posted by apollard View Post
No, they are not interchangeable, the V will retard all the time w/o the knock module present.
Ok thanks i will try a complete MSD system and hope that will work
markku4444 is offline  
Reply With Quote
Old 07-14-2010, 08:34 AM
  #6
Registered
 
Join Date: Nov 2005
Location: Fredericksburg, Va
My Boat: Checkmate 251 Convincor(sold),Checkmate 253 Convincor(sold), 50 gibson, 21 Eliminator Daytona, 25 Sportcraft Center Console
Posts: 4,439
Default

put a HEI in it, run no vacume advance, set your total timing, simple works great...
ezstriper is offline  
Reply With Quote

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


OSO Sponsor
OSO Advertiser
OSO Advertiser
OSO Advertiser