I am hearing about rubber degradation with the NAPA cap and apparent leakage on installs without a plug installed. There must be a compatibility problem with the NAPA rubber and the anti-freeze. Please accept my apology for not foreseeing this problem. The cap from NAPA is designed for this type of application.
My concern, with the first install, was the possibility of the cap coming off under pressure with the use of a light tension CT clamp. My thought process concluded a plug must be installed for safe measure. It may turn out to be a key piece to the install. I made the plug out of delrin. The kits from Rodgers Sport Center have them. If you make one be sure you put a shoulder on it so it doesn't migrate into the thermostat housing.
I'm on the road, and don't have the dimensions with me. Make sure it fits snug, needs to be pushed in.
My concern, with the first install, was the possibility of the cap coming off under pressure with the use of a light tension CT clamp. My thought process concluded a plug must be installed for safe measure. It may turn out to be a key piece to the install. I made the plug out of delrin. The kits from Rodgers Sport Center have them. If you make one be sure you put a shoulder on it so it doesn't migrate into the thermostat housing.
I'm on the road, and don't have the dimensions with me. Make sure it fits snug, needs to be pushed in.
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