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Best adhesive for PCV diaphragm?

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TR4A_IRS

TR4A_IRS

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Any suggestions for a good adhesive to attach a PCV diaphragm to the plunger? Mine have separated and I am planning to replace the diaphragm. I think I used RTV the last time I made this repair, and I think it lasted more than five years. However I feel like there must be a better adhesive out there for this task.
 
Ian,

I didn't think the diaphragm and plunger were supposed to be attached? Admittedly my experience has been limited since my original TR4A had the PCV removed so just going by ancient memory with my wife's 68 Spitfire which used the same PCV design and looking at the one on my second TR4A.

Scott
 
I have seen a couple of different types of diaphragms so I guess there may be some where the plunger attached... but I haven't seen them. RTV is probably as good as any adhesive in this environment since you need the joint to remain flexible. As with any glue joint, make sure the surface is clean and dry before proceeding and for the RTV give the assembly over-night to cure before use.
 
Yeah I'm with Scott on this one. The diaphragm isn't attached or adhered to the plunger - although after a time, a thin layer of oil will form between the two and the plunger will tend to briefly stick to the diaphragm when you go to take it out (typically falling down into the engine compartment before you can save it).
 
Well, there goes my theory. I thought I had found the vacuum leak I have been chasing...
 
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