The Fishing Website : Discussion Forums : how to test outboard compression?

The Fishing Website : Discussion Forums : how to test outboard compression? https://www.fishing.net.nz/forum/ Sat, 30 May 2026 05:47:10 +0000 Sat, 03 Mar 2012 01:08:19 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 12.01 360 https://www.fishing.net.nz/forum/RSS_post_feed.asp?TID=76291 <![CDATA[The Fishing Website : Discussion Forums]]> https://www.fishing.net.nz/forum/forum_images/web_wiz_forums.png https://www.fishing.net.nz/forum/ <![CDATA[how to test outboard compression? : ^ You chaps do know that the phosphorescence...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1089231&title=how-to-test-outboard-compression#1089231 Author: Unclejake
Subject: 76291
Posted: 03 Mar 2012 at 1:08am

^ You chaps do know that the phosphorescence we often see when boating at night is left over sparks from guys with loose fitting engine covers?]]> Sat, 03 Mar 2012 01:08:19 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1089231&title=how-to-test-outboard-compression#1089231 <![CDATA[how to test outboard compression? : It's not as silly as it sounds...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1089182&title=how-to-test-outboard-compression#1089182 Author: smudge
Subject: 76291
Posted: 02 Mar 2012 at 9:57pm

It's not as silly as it sounds Tugboat..... if you put a fish in the bucket you could cook it at the same time Clown

]]> Fri, 02 Mar 2012 21:57:09 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1089182&title=how-to-test-outboard-compression#1089182 <![CDATA[how to test outboard compression? : Mullins wrote: You could...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1089062&title=how-to-test-outboard-compression#1089062 Author: tugboat
Subject: 76291
Posted: 02 Mar 2012 at 6:47pm

Mullins wrote:

You could put all the leads into a bucket to catch the sparks? A plastic one, obviously. Then you could tip a couple out whenever you wanted to light fires.

what you been smoken mullins!!

]]> Fri, 02 Mar 2012 18:47:28 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1089062&title=how-to-test-outboard-compression#1089062 <![CDATA[how to test outboard compression? : Onan old Johnson I hadturning...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088902&title=how-to-test-outboard-compression#1088902 Author: Kevin.S
Subject: 76291
Posted: 02 Mar 2012 at 12:18pm

On an old Johnson I had turning the engine over with the spark plugs out could destroy the ignition unit. I had a steel plate with three holes for the spark plugs to screw in to and this earthed to the engine. That way I could check the compression and that the sparks were good at the same time.

]]> Fri, 02 Mar 2012 12:18:52 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088902&title=how-to-test-outboard-compression#1088902 <![CDATA[how to test outboard compression? : Question...If some one turned...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088830&title=how-to-test-outboard-compression#1088830 Author: Jet_ski_fisher
Subject: 76291
Posted: 02 Mar 2012 at 9:29am

Question...If some one turned on the kill switch first on a 2 poke, then took off number 1 S/P lead and held it with a rubber glove and with the free hand inserted the compression tester into the number 1 cyl and cranked it 2 seconds to get compression would that do any damage even if it is not a efi engine.]]> Fri, 02 Mar 2012 09:29:12 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088830&title=how-to-test-outboard-compression#1088830 <![CDATA[how to test outboard compression? : On EFI motors we can disconnect...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088812&title=how-to-test-outboard-compression#1088812 Author: Outboard Performance
Subject: 76291
Posted: 02 Mar 2012 at 8:29am

On EFI motors we can disconnect crank position sensor so the motor doesnt think it is being cranked over, hence no spark generated.
We can have lanyard or kill switch off and crank motor which isolates spark.

You can have key turned off, then jump start starter solenoid with a wire to save getting in and out of boat to crank.

We also have a special tool to plug into HT spark plug leads that earths the spark, and makes the spark jump a pre set gap so we can test the ignition at the same time.
]]> Fri, 02 Mar 2012 08:29:28 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088812&title=how-to-test-outboard-compression#1088812 <![CDATA[how to test outboard compression? : I'm sure they would. ]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088735&title=how-to-test-outboard-compression#1088735 Author: smudge
Subject: 76291
Posted: 01 Mar 2012 at 10:35pm

I'm sure they would.]]> Thu, 01 Mar 2012 22:35:24 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088735&title=how-to-test-outboard-compression#1088735 <![CDATA[how to test outboard compression? : How do the boat dealers do there...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088705&title=how-to-test-outboard-compression#1088705 Author: Jet_ski_fisher
Subject: 76291
Posted: 01 Mar 2012 at 9:53pm

How do the boat dealers do there psi checks? wonder if they take precautions on the wiring as well?]]> Thu, 01 Mar 2012 21:53:17 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088705&title=how-to-test-outboard-compression#1088705 <![CDATA[how to test outboard compression? : Yes it does Chris, you should...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088661&title=how-to-test-outboard-compression#1088661 Author: smudge
Subject: 76291
Posted: 01 Mar 2012 at 8:52pm

Yes it does Chris, you should always operate the kill switch if you're cranking it over with the leads off for several reasons: a handy little fire is one of those reasons, a nasty shock is another. I know in the early days CDI ignitions didn't like an open circuit but not sure about modern systems - I'd play it safe, then there's the possibility of a big voltage hitting other electronic devices or even passing through the low voltage wiring. The insulation on the 12v stuff want stop kilovolts.

The best answer though comes from Mullins Big smile

]]> Thu, 01 Mar 2012 20:52:05 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088661&title=how-to-test-outboard-compression#1088661 <![CDATA[how to test outboard compression? : Blue Legend wrote:if you have...]]> https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088612&title=how-to-test-outboard-compression#1088612 Author: Dunwurkn
Subject: 76291
Posted: 01 Mar 2012 at 7:23pm

Blue Legend wrote:

if you have all the plugs out, and crank the engine, wouldn't the spark have nowhere to go? maybe fry the computer and/or coil pack? I don't know for sure thats why its a question.

Anyone 1 have any further info on this comment? Does unplugging the kill switch stop the spark from forming?]]> Thu, 01 Mar 2012 19:23:00 +0000 https://www.fishing.net.nz/forum/forum_posts.asp?TID=76291&PID=1088612&title=how-to-test-outboard-compression#1088612