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TOPIC: Early CIS O-Ring Issues

Early CIS O-Ring Issues 15 Feb 2021 08:40 #21765


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Now that I have gone through my '79's CIS system and that it seems to be running fairly well, I wanted to ask if others have reoccurring issues with the fuel distributor O-rings, particularly the two with the pressure regulator. Those two O-Rings appear to really take a beating.
CISFlowTech point to ethanol in the fuel.
I'm sure that's right and also lack of use that allows them to dry out.
I'm just wondering if people have any magic bullets, like a Viton O-Ring supplier!
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Early CIS O-Ring Issues 22 Feb 2021 12:48 #21784


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joejabq wrote:
Now that I have gone through my '79's CIS system and that it seems to be running fairly well, I wanted to ask if others have reoccurring issues with the fuel distributor O-rings, particularly the two with the pressure regulator. Those two O-Rings appear to really take a beating.
CISFlowTech point to ethanol in the fuel.
I'm sure that's right and also lack of use that allows them to dry out.
I'm just wondering if people have any magic bullets, like a Viton O-Ring supplier!

After consulting with Rich and others with early model year cars, I’m now thinking that 10% ethanol is not an issue. I’m starting to think that letting the o-rings dry out, either from lack of use or having a system that doesn’t retain residual fuel pressure (I had both of these) is the more important factor.
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