Diverter Valve Rebuild Source Needed,... I Think?

[musclecar fan]

I have a 69 SS 350 and need my smog diverter valve rebuilt, I think. On de-acceleration or between shifts I get backfire noises out of my exhaust. I never had this before, but since re-installing my A.I.R. smog equipment now I do. Any thoughts on what is causing this? maybe the gasket between the diveter valve and the tube where it attaches is bad....? Help..... Thanks

[CamarosRus]

Bill Hoedel has an exclusive arrangement with Don D. (ex from ASL)..... FYI

I myself would like to what the alternative is, at what quality and what price.

Pretty sure Don D is only rebuilder to ever R&R Yellow Zinc cover, and replate !!!!!!!

[Xplantdad]

[ QUOTE ]
I have a 69 SS 350 and need my smog diverter valve rebuilt, I think. On de-acceleration or between shifts I get backfire noises out of my exhaust. I never had this before, but since re-installing my A.I.R. smog equipment now I do. Any thoughts on what is causing this? maybe the gasket between the diveter valve and the tube where it attaches is bad....? Help..... Thanks

[/ QUOTE ]


On a working smog set up...I think that this is normal (which is one of the reasons why everyone took them off... http://www.yenko.net/ubbthreads/images/graemlins/tongue.gif )

I could be wrong though... http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[Charley Lillard]

What you are hearing is the smog system doing it's job. It is injecting air and allowing combustion of the unburnt fuel in the exhaust.

[mockingbird812]

Be proud that you are doing your little part in preserving our environment! http://www.yenko.net/ubbthreads/images/graemlins/laugh.gif http://www.yenko.net/ubbthreads/images/graemlins/smirk.gif http://www.yenko.net/ubbthreads/images/graemlins/hmmm.gif http://www.yenko.net/ubbthreads/images/graemlins/wink.gif http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

[MosportGreen66]

If the system does need rebuild, I unconditionally recommend Bill Hodel!

[Xplantdad]

[ QUOTE ]
What you are hearing is the smog system doing it's job. It is injecting air and allowing combustion of the unburnt fuel in the exhaust.

[/ QUOTE ]

Thanks Charley!

[Mr70]

How loud & routine is it?
You really shouldn't hear enough to be that noticeable all the time.
It could be the pressure relief valve inside the diverter sticking open,or not at all.Do you have manifold,(not ported),vacuum running into the Diverter valve itself?
Does the Smog system you put back on it have a working pump w/guts,or is it a dummy pump w/operating diverter valve?
Just for kicks,check your dwell & ignition timing with a timing light too.

[musclecar fan]

The system is stock with full functioning smog pump with the guts intact. I routed the 1/4 inch hose from the back of the diverter valve to the side nipple on the side of the quadrajet carb on the passenger side. The kit also came with a white "T" but I didn't know where that went. There is also a 1/4 hose that runs from the back of the intake to the distributor vacuum advance. Should I "T" off of that?

As to when it makes the back-fire/ popping noises, my car is a 4sp and when I wind out first and shift to second I hear the noise. Also if I'm going down a steep hill and coast in gear at speed down the hill I hear it as well.

[JIM]

I have been doing the rstoration of these valves for years in the correct cynadide cadiumn not the cheap alkalide cadiumn that everybody else uses!!!!!
Jim

[Johnny Horsepower]

[ QUOTE ]
The system is stock with full functioning smog pump with the guts intact. I routed the 1/4 inch hose from the back of the diverter valve to the side nipple on the side of the quadrajet carb on the passenger side. The kit also came with a white "T" but I didn't know where that went. There is also a 1/4 hose that runs from the back of the intake to the distributor vacuum advance. Should I "T" off of that?

As to when it makes the back-fire/ popping noises, my car is a 4sp and when I wind out first and shift to second I hear the noise. Also if I'm going down a steep hill and coast in gear at speed down the hill I hear it as well.

[/ QUOTE ]

I had the EXACT same issue with my 70 Z28 4spd. I tried timing etc. In the end we put it on the dyno, and tried some things. Here is what worked. Freeze plugs on both sides of the air unit.
Has been running great ever since.

John

['69Novajoe]

I remember having this problem on the Nova. And like Rick (mr70) mentioned, the vacuum hookup was my problem. Make sure it is manifold vacuum. I had switched the vacuum advance line with the diverter line. Problem solved!!
Joe

[CamarosRus]

JIM, May we SEE pictures of your divertor valve work and be quoted a price and contact info.

I have at least one 297 & 295 that need cosmetic and mechanical (???) attention.