Heater knob removal

[DavidApp]

I am starting to work on the donor dash for my 74 MG Midget. I can't get the knob off the heater manual valve shaft. The book mentioned a pin that needs to be depressed but I have looked in the hole in the knob aligned with "Low" and do not see a pin. The knob turns a bit on the shaft and I have turned it as far as possible in both directions with no sight of a pin??

David

 

[Jim_Gruber]

On a Bugeye the PIn is on the bottom of the knob, Between the H on the underside. The Knob is designed to rotate with the knob pushed in to turn on the heater fun. I can't remember how Temps are controlled on a 74, but if there is a big H Knob there will be a tiny hole on the bottom of the knob where you depress the lock button to remove the knob.

 

[Madflyer]

Even with the pin pushed in still a good pull to remove knob.

 

[DavidApp]

Thank you for the info.
Got it off with some difficulty. Nothing was damaged in the process. Seems the small pin and spring were displaced by the knob being turned while the mechanism behind was frozen. Some penetrating oil last night, a small screw driver in the hole and one applying some outward pressure the knob came off.
The small spring that pushes on the pin is almost broken so if I reuse the mechanism I will have to come up with a way of holding the knob.

 

[Nelson]

Thank you for the info.
Got it off with some difficulty. Nothing was damaged in the process. Seems the small pin and spring were displaced by the knob being turned while the mechanism behind was frozen. Some penetrating oil last night, a small screw driver in the hole and one applying some outward pressure the knob came off.
The small spring that pushes on the pin is almost broken so if I reuse the mechanism I will have to come up with a way of holding the knob.

How about using a small tap and a set screw?

 

[DavidApp]

That is what I was thinking of doing. I have a good assortment of suitable screws, Metric and standard even BA.

Moving on with the dash the donor dash I have has direction indicator lights with a chrome arrow but unfortunately both have broken off where the green plastic screws into the bulb holder. Does anyone have a source for replacement plastic pieces with the chrome arrow. Someone has very kindly sent me an orphan spare one they had. I was thinking I could get some green plexiglass rod and make a new stem if I had to.

David

 

[DrEntropy]

This makes for more advantages for 3D additive manufacturing. Rare bits like the plastic insert could be made "one off" to order. The only real problem/issue would be finding an OEM part for each one, to use to make the CAD drawings. Initially costly, but ~somebody~ is bound to do it.