I did a leakdown test on my 2001 KDX 200 this afternoon.
I've never done one before and used a homemade tester that I put together.
I pressurized it to 5.5 lbs psi and it lost .75 lb over 10 minutes.
My question is is this an acceptable loss rate or does it indicate the engine has a problem that requires attention?
interpretting leakdown test results
-
- Gold Member
- Posts: 165
- Joined: 09:30 pm Mar 15 2015
- Country:
- KDXGarage
- KDXRider.net
- Posts: 14047
- Joined: 06:45 am Nov 01 2004
- Country: United States of America
- Location: AL, USA
- Contact:
Re: interpretting leakdown test results
From what I have read, that is very good.
Thank you for participating on kdxrider.net.
To post pictures from a device: viewtopic.php?f=88&t=24128
To post pictures from a device: viewtopic.php?f=88&t=24128
-
- Gold Member
- Posts: 165
- Joined: 09:30 pm Mar 15 2015
- Country:
Re: interpretting leakdown test results
I think I'll need to re-do the test.
I read last night that the piston should be at BDC.
I missed that step.
I read last night that the piston should be at BDC.
I missed that step.
- Julien D
- KDXRider.net
- Posts: 5858
- Joined: 07:53 pm Nov 07 2008
- Country: USA
- Contact:
Re: interpretting leakdown test results
I would think at BDC you'd be checking only for head gasket and rings, IE: top end leak. At or close to TDC will pressurize the crankcase and test the crank seals.
-
- Gold Member
- Posts: 875
- Joined: 06:59 am Jan 27 2017
- Country: US
- Location: Florida
Re: interpretting leakdown test results
I've always heard the opposite. It had something to do with the transfer ports not being blocked by the piston when the piston is at BDC.
Edit: Motion Pro's website says that the leakdown is done with the piston at BDC. It also says that 1psi per minute of loss is acceptable. I don't know about all that. If i pumped up an engine to 6psi and 6 minutes later it was at zero, I would fix the leak. If you retest and it barely loses any psi like your last test I would say its good to go.
I've also read but forget where that you should have your radiator cap removed during a leak down test to make sure no air is being pushed into the cooling system. Keeping the cap on could mask an issue.
-
- Gold Member
- Posts: 165
- Joined: 09:30 pm Mar 15 2015
- Country:
Re: interpretting leakdown test results
Thank you, John. This is good information.John_S wrote: ↑08:37 am Mar 04 2019
I've always heard the opposite. It had something to do with the transfer ports not being blocked by the piston when the piston is at BDC.
Edit: Motion Pro's website says that the leakdown is done with the piston at BDC. It also says that 1psi per minute of loss is acceptable. I don't know about all that. If i pumped up an engine to 6psi and 6 minutes later it was at zero, I would fix the leak. If you retest and it barely loses any psi like your last test I would say its good to go.
I've also read but forget where that you should have your radiator cap removed during a leak down test to make sure no air is being pushed into the cooling system. Keeping the cap on could mask an issue.
- Julien D
- KDXRider.net
- Posts: 5858
- Joined: 07:53 pm Nov 07 2008
- Country: USA
- Contact:
Re: interpretting leakdown test results
Wasn't thinking of the transfer ports, as long as they are open when the test is run, then yes you are good.