The cap on the main tank (the one with the big hoses from the engine) has the pressure cap, no argument there.
The expansion tank, has a hole in the neck, so if a regular pressure cap is uses there, then YES, this is incorrect, as there will be no way for the coolant to flow up or down.
But if a sealed cap is used (cap with round rubber piece) then that doesn't impede the coolant and air from flowing in and out through the vent tube on the expansion tank. Look at the diagram pic you posted (#21).
The issue arises when you put a regular radiator cap on the expansion tank, which makes a seal BELOW the hole in the neck of the expansion tank. This keeps the system completely sealed and may cause pressure problems I would assume.
quote:Originally posted by LF - TP 2511:quote:I recently called around to a few Pantera shops, and they said run it sealed.
Would that be the vendor that has sold Windsor thermostats for our Cleveland engines?
Perhaps the vendor that told me, with all sincerity, that it is not necessary to have the ZF ring and pinion bolts safety wired?
Maybe the vendor that sold Lord-knows-how-many reproduction, "bolt-in" clutch master cylinders that had such cheap o-rings that they tended to dissolve and fall apart, sometimes within days of installation?
Perhaps the vendor who told me there are only two versions of the left and right side marker lights? In truth, each side marker corner has its own, unique design and they are marked with different part numbers. I've got all four if anyone needs photographic proof.
Or maybe the vendor that sold, for years, fiberglass front "L" bumpers that were about 2" narrower than the factory original unit?
I could go on....
Bottom line, our vendors are vital to our marque, but they are not always correct.
My 2ยข
Larry
There are Ford Pantera manuals indicating the surge-pressure-shorter tank uses a 13# cap.
Those same manuals make no note of a pressure rating for the expansion tank, just calling it a cap.
The caps for the two tanks are listed with different part numbers.
The manual illustration clearly shows two different styles of caps.
Again, I am pleased your car runs fine with a pressure cap on the expansion tank.