Mystery hole on floor below convertible piston - Pontiac GTO Forum
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post #1 of 6 (permalink) Old 01-15-2018, 09:42 PM Thread Starter
 
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Mystery hole on floor below convertible piston

I am preparing my convertible for paint and have found a hold in the rear floor below the convertible piston. The hole is rather large and on both sides (left and right), so it appears to be intentional. That said, it will allow water and dirt (as well as rodents) to easily enter the car.

Should there be a plug in these? Are they for drainage ? Thanks

Chris
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1965 GTO Convertible 3 speed tri-power drum brakes originally

Current setup:
400 cu in with tri-power
4 speed Muncie
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post #2 of 6 (permalink) Old 01-15-2018, 11:16 PM
 
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Originally Posted by cij911 View Post
I am preparing my convertible for paint and have found a hold in the rear floor below the convertible piston. The hole is rather large and on both sides (left and right), so it appears to be intentional. That said, it will allow water and dirt (as well as rodents) to easily enter the car.

Should there be a plug in these? Are they for drainage ? Thanks

Chris
My guess is that it is a drain for any hydraulic fluid that might leak from the cylinders.
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post #3 of 6 (permalink) Old 01-16-2018, 05:51 AM
 
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I think it would be a dual purpose, IIRC the pinchweld gutter is set up to direct water to those points as well.
I don't recall plugs but there likely should be.

GTO Jr. - A.K.A. SPRINT 6
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post #4 of 6 (permalink) Old 01-16-2018, 09:36 AM Thread Starter
 
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Thanks guys! Any idea what book might have detailed information on the purposes and whether there should be a rubber drain plug ? Thanks

-- Chris

1965 GTO Convertible 3 speed tri-power drum brakes originally

Current setup:
400 cu in with tri-power
4 speed Muncie
cij911 is online now  
post #5 of 6 (permalink) Old 01-16-2018, 08:18 PM
 
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slightly different - but maybe helpful?

I almost hesitated to post because It's not the same - but a few years later model. My thinking was that design solutions don't evolve that quickly unless the design is poor. Let's all agree the 65 is a great design. So my assumption is that what is design used my car is similar to the 65. I've been more active on this forum this winter - trying to learn like lots of us.


So I looked at photos taken early in the resto of my '68 - 24267. Mine does not have any tray shaped stampings as shown in your post. However, there ARE 4 plugged holes in the floor in the cabin side of the rear bulkhead. They are more or less equally spaced laterally along the transition of the flat floor and curved floor over the rear axle. They are light colored whiteish or cream colored and have been sealed (grey caulk) around the inside where the plug protrudes into the cabin space.

These would be under the seat - and clearly would not be left open to the elements from the factory.

I think these through holes should be plugged.

HTH

DK

<)))>><

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Last edited by integrity6987; 01-16-2018 at 08:21 PM. Reason: added comment
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post #6 of 6 (permalink) Old 01-16-2018, 10:39 PM Thread Starter
 
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Originally Posted by integrity6987 View Post
I almost hesitated to post because It's not the same - but a few years later model. My thinking was that design solutions don't evolve that quickly unless the design is poor. Let's all agree the 65 is a great design. So my assumption is that what is design used my car is similar to the 65. I've been more active on this forum this winter - trying to learn like lots of us.


So I looked at photos taken early in the resto of my '68 - 24267. Mine does not have any tray shaped stampings as shown in your post. However, there ARE 4 plugged holes in the floor in the cabin side of the rear bulkhead. They are more or less equally spaced laterally along the transition of the flat floor and curved floor over the rear axle. They are light colored whiteish or cream colored and have been sealed (grey caulk) around the inside where the plug protrudes into the cabin space.

These would be under the seat - and clearly would not be left open to the elements from the factory.

I think these through holes should be plugged.

HTH
Thanks!

1965 GTO Convertible 3 speed tri-power drum brakes originally

Current setup:
400 cu in with tri-power
4 speed Muncie
cij911 is online now  
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  Pontiac GTO Forum > The 1964-1974 Pontiac Tempest, Lemans & GTO > 1964-1974 Tempest, Lemans & GTO Convertible Top, Interior, Glass and Trunk

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