1969 Proportioning valve question

[Greg R.]

Hi:
I have a question regarding my 1969 Proportioning valve that needs replacement.
My '69 is an early car (11/5/1968). Would I need to order a 1969 or 1968 valve as I know my car shares alot of '68 parts due to its early production ? Thanks in advance.

[Joe L.]

Re: 1969 Proportioning valve question

Greg-----

NO 1969 Corvette ever used a brake proportioning valve. Absolutely none.

If you are talking about the brake distribution block and pressure differential warning switch, the 1969 unit was unique to the 1969 model year. As far as I know, the 67-68 part was not used for any 1969s. I've never seen the 67-68 part on a 1969.

[Greg R.]

Re: 1969 Proportioning valve question *NM*

[Greg R.]

Re: 1969 Proportioning valve question

Thank you Joe...The mechanic who works on my car called me today and told me to pick up a new "proportioning valve", so I wanted to inquire first.
Thanks again.
Greg

[Joe L.]

Re: 1969 Proportioning valve question

Greg------

Many people THINK that these devices are "proportioning valves", but they are not. Also, they do not often fail in any way that affects brake system operation. The 1969 valve may now be available in reproduction or, at least, rebuilt. Save the old one in case you need it for a core.

The only Corvettes that ever had a brake proportioning valve were 1966-68 with J-56 and 1978-82. The 66-68 J-56 valve was adjustable; the 78-82 valve, which was part of the brake distribution and pressure differential sensing switch, was of fixed calibration.

[Jeffrey S.]

Re: 1969 Proportioning valve question

What generally fails is the switch that warns of unequal brake fluid pressure. Are these available anywhere to replace defective ones?
Jeff

[Joe L.]

Re: 1969 Proportioning valve question

Jeff-----

Yes, that's the part that usually fails. I don't know of a source for them, but I'll bet there is such a source. I have a feeling that this electrical component has wider applications, automotive and non-automotive.

[Verle R.]

Re: 1969 Proportioning valve question

" I've never seen the 67-68 part on a 1969. "

Joe,

I have to disagree with you in picky detail.
Early 69s came with the 68 grill. That is, the front edge was silver. Most 69s had black (unpainted) front edges.

Verle

[Joe L.]

Re: 1969 Proportioning valve question

Verle-----

There's no disagreement. I was talking only about the 67-68 brake fluid distribution and pressure differential warning switch. There are quite a few parts that would be considered 1968 that appear on early 69's. In fact, there are MANY parts common to 67-68 which are also used for 1969 (and, much later, too).