Go Back  Offshoreonly.com > Technical > General Q & A
Rev engine to check plugs >

Rev engine to check plugs

Notices

Rev engine to check plugs

Old 10-22-2022, 04:13 PM
  #1  
Registered
Thread Starter
 
Join Date: Aug 2017
Location: Gold Coast OZ
Posts: 32
Likes: 0
Received 0 Likes on 0 Posts
Default Rev engine to check plugs

Hi guys, I'm trying to get an answer on when to check plugs. I know his may sound odd, but I want to know how well or not my engines are running.
After running I feel I have to idle too long to get a good read.
can I rev engine up to 3000 for a few mins and then check? or is this not wise. Can someone please tell me how you do it properly in a boat.
cheers
Waterlife is offline  
Old 10-22-2022, 05:42 PM
  #2  
Registered
 
Join Date: Aug 2007
Location: Merritt Island, FL
Posts: 1,270
Received 909 Likes on 419 Posts
Default

Increasing revs with no load will not be an accurate way to assess burn. Ideally you do "plug cuts" where you run at wide open throttle, then cut the throttle back to idle very quickly and kill the ignition. That allows you to see what the burn is like at wide open throttle without the effects of a prolonged idle changing the way the plugs look.
DrFeelgood is offline  
The following 5 users liked this post by DrFeelgood:
1983ScarabIII (10-22-2022), articfriends (10-24-2022), Bondo (10-23-2022), jeff32 (10-22-2022), speicher lane (10-22-2022)
Old 10-22-2022, 05:46 PM
  #3  
Platinum Member
Platinum Member
 
jeff32's Avatar
 
Join Date: Jun 2004
Location: St-Hyacinthe, quebec, canada
Posts: 7,476
Received 238 Likes on 168 Posts
Default

I second this method!
jeff32 is offline  
Old 10-22-2022, 06:44 PM
  #4  
Registered
Thread Starter
 
Join Date: Aug 2017
Location: Gold Coast OZ
Posts: 32
Likes: 0
Received 0 Likes on 0 Posts
Default

Thanks guys, How long do I need to run for at the desired rpm to get a good read?
Waterlife is offline  
Old 10-22-2022, 07:14 PM
  #5  
Registered
 
Join Date: Aug 2007
Location: Merritt Island, FL
Posts: 1,270
Received 909 Likes on 419 Posts
Default

Originally Posted by Waterlife View Post
Thanks guys, How long do I need to run for at the desired rpm to get a good read?
Maybe 60-90 seconds... should be adequate
DrFeelgood is offline  
Old 10-22-2022, 07:39 PM
  #6  
Registered
Thread Starter
 
Join Date: Aug 2017
Location: Gold Coast OZ
Posts: 32
Likes: 0
Received 0 Likes on 0 Posts
Default

Cheers
Waterlife is offline  
Old 10-22-2022, 09:34 PM
  #7  
Registered
 
Join Date: Mar 2020
Posts: 261
Received 121 Likes on 78 Posts
Default

You can do the same method at your cruise RPM also. Be careful. Completely chopping the throttle on some boats may cause it to hook one way or the other.
Smitty275 is offline  
Old 10-23-2022, 12:51 PM
  #8  
Platinum Member
Platinum Member
iTrader: (7)
 
getrdunn's Avatar
 
Join Date: Feb 2009
Location: NW Michigan
Posts: 7,967
Received 1,300 Likes on 676 Posts
Default

Id also start with a couple new plugs on the hotter cylinders like 7 & 8. As mentioned your cruising rpm is extremely important also as you spend most your time there. JMO
getrdunn is offline  
The following users liked this post:
articfriends (10-24-2022)
Old 10-23-2022, 05:00 PM
  #9  
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha/LOTO
Posts: 19,152
Received 1,409 Likes on 696 Posts
Default

Make sure you really know how to read the plugs as well. Its not just looking at the color on the porcelain.
Griff is offline  
Old 10-24-2022, 08:10 PM
  #10  
Registered
Thread Starter
 
Join Date: Aug 2017
Location: Gold Coast OZ
Posts: 32
Likes: 0
Received 0 Likes on 0 Posts
Default

As far as im aware, im looking for a brown/ grey colour!!! Not Black - too Rich or whitish - too lean....
Saying that - i have my setup on the richer side to start with, so most likely be black
Thanks to all for your help - will do as discussed and see how i get on...
Waterlife 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 - Do Not Sell or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.