# 2013 yamaha 4 stroke 70hp compression



## monte (Apr 8, 2013)

cold compression test done on a 2013 yamaha 4 stroke 70hp 
numbers are between 95- 105psi. does this seem right? around 150 hours. seems real low for such a new motor.


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## DuckNut (Apr 3, 2009)

I think compression should be checked on a warm engine. No idea what the compression should be.


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## Brett (Jul 16, 2008)

Make sure intake flap is wide open when testing compression.
With the butterfly closed it restricts airflow, giving lower readings.


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## cutrunner (Jun 8, 2010)

Its fine
Go find two other guages and see what they say. 
Guarante you they wil all be different. Possibly higher or lower


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## cutrunner (Jun 8, 2010)

But I will buy it off of you for a discounted sum ;D


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## Creek Runner (Sep 1, 2011)

Yamaha no longer recommends compression test on 4-stroke engines, A leak down test should be performed.


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## cutrunner (Jun 8, 2010)

Agreed. Its a little more work but if you know what your doing it can tell you ANYTHING you need to know


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## cutrunner (Jun 8, 2010)

Creek
I'm up here at yamaha right now. 
Need any parts?


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## monte (Apr 8, 2013)

its for a boat that im looking at picking up. boats not in my area and the owner took it to a dealer to for a check up. every thing else seems good. i may run my own when i see the boat in person.


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## Creek Runner (Sep 1, 2011)

> Creek
> I'm up here at yamaha right now.
> Need any parts?


All I need is a hole in my head for working on boats!


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