Hello All! Well it seems my C90 has been leaving a large oil spot after flying. I have been tracing it and there is a stream of oil down the middle of the tank that seems to be coming from the mounting flange. There has been some patching done to it apparently and it doesn't use a lot of oil but it's a mess and I want to fix it. Some have said it could be the gasket (seems to easy). So I have some questions:
Is there a type of gasket that would be better to use?
Is there any way to leak test it to find the crack?
Does anyone have a used one for sale?
I have a welder who hopefully can repair it and if anyone has had any experience with this or helpful comments, please let me know!
Thanks
John Sharkey
Leaky Oil sump tank
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6555
- Posts: 29
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- Name: John Shahkey
- Aircraft Type: c140
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6643
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Re: Leaky Oil sump tank
I made a steel plate to cover the big round hole on top and found a generic unvented gas cap (or was it an oil fill cap?) and put an air chuck in it. Not sure if I could lay my hands on it today: I know that at some point long ago someone had walked off with some or all of the kit, and I'm not sure if I got it back, or replaced the missing parts.
Cracks where the tank is welded to the flange are common. If you look at an O-200 tank you will see they added some braces between the tank and flange. If you decide to add some, be careful where you put them. Access to the mounting nuts is hard enough without them.
Cracks where the tank is welded to the flange are common. If you look at an O-200 tank you will see they added some braces between the tank and flange. If you decide to add some, be careful where you put them. Access to the mounting nuts is hard enough without them.
John Cooper
www.skyportservices.net
www.skyportservices.net
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Re: Leaky Oil sump tank
0-200 Oil tank for sale!
$900 plus shipping.
$900 plus shipping.
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6555
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- Joined: Sun Jul 15, 2018 7:32 pm
- Name: John Shahkey
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Re: Leaky Oil sump tank
Thanks for the info I will pull it this week!6643 wrote: ↑Fri Oct 24, 2025 6:31 pm I made a steel plate to cover the big round hole on top and found a generic unvented gas cap (or was it an oil fill cap?) and put an air chuck in it. Not sure if I could lay my hands on it today: I know that at some point long ago someone had walked off with some or all of the kit, and I'm not sure if I got it back, or replaced the missing parts.
Cracks where the tank is welded to the flange are common. If you look at an O-200 tank you will see they added some braces between the tank and flange. If you decide to add some, be careful where you put them. Access to the mounting nuts is hard enough without them.