Mystery device mounted to heat shield btw SU's

[RustyBucket]

So I'm finally getting around to restoring a "late" 69 SPL which has a strange electrical device bolted to the middle of heat shield plate between the SU's . It has two wires about 3.5 inches long hanging out of it, one Black the other is Black/White tracer.

There does not seem to be part of the wiring harness to which these wires are to "plug" in to..

The early '69 SPL I owned back in '73, I don't believe had this device. Is it some type of "smog" device and is it required to get my car running correctly ?? All the rest of the SMOG pump jazz is still mounted in the engine bay (taking up room)

Any ideas from you all since you've had to have seen one of these gizmo before ??

Also- can someone recommend a shop that can rebuild the SU's at a reasonable cost?
Many Thanks,
Cam

[keith0alan]

Emission control bit unique to the '70 1600.

[bakerjf]

Early flux capacitor. Keep it under 88mph.

[RustyBucket]

Well there has to be Documentation , SO WHERE for the this dodgy bit ! It was not on my first SPL, but this later model has the do-dad and the flat fuel vapor condenser tank bolt to the back of the trunk.. A "SPACE SAVING" location that is... (not)

Are there Docs on these gizmo? Does it just get triggered from the heat conducted from the shield ? There is no mechanical linkage. Just electrical connections..

Maybe it is a Flux Capacitor..after all ... ( Back to the Future is filmed in '85)

[keith0alan]

Documentation is a bit hard to find. The service manual does not cover it at all. It seems to consist of the solenoid valve on the manifold that has lines to the carbs and a switch on the transmission. The solenoid appears to allow a little extra fuel/air into the manifold when the transmission is in one or more gears. What could it's function be? My thoughts are that it is anti-backfire. With the bit of extra fuel/air under overrun conditions it would be less likely to backfire through the exhaust. Backfiring creates lots of unburned hydrocarbons and such things. The Z car had a vacuum driven bit that opened the throttle a little under high manifold vacuum performing this function. Some of the British SU carbs had a little spring loaded valve on the carb butterfly. There are several different wiring diagrams floating around. One of them might have the wiring for this. Anyway, that would be my guess.

[RustyBucket]

Many Thanks for that ... Your explanation appear to define a slight backfire issue with the car before it's 7 year nap in the garage. Odd though is that fact that there fail to be any mechanical linkage on the device. Only the two wire leads as I mention. Additionally the wiring harness has no dangling disconnected access points.

Your comment about BMC cars' SU carburetors with their spring loaded butterflies is interesting. I read that the British had sold the basic design of the inline 4 Morris engine to Japan back in the late 1930's - If I remember correctly. So the Japanese had an electrical/mechanical - solution where as the Brits went "spring Loaded" . Not a hard decision for the Brits as they had "Lucas -Prince of Darkness - electricals in their cars.."

Maybe trolling the Web will reveal the meaning of this gizmo.
Thanks Again,
Cam

[spl310]

It is covered in the separate emission control manual. It is often called a "gulp" valve.

[RustyBucket]

In this case a Big "gulp" ..
As it turns out, there are two electrical connections to the gulp valve, but no type of linkage. So how does it work?? Is it just a rely that closes when the engine gets to a certain temperature ?

[fj20spl311]

That is NOT a Glup Valve.
A Glup valve is part of the Air injection system into the exhaust and is vacuum controlled. The internet is your friend.

There were some cars that had a leaning mechanism for when the car was in higher gears or above something like 35 mph.

[fj20spl311]

The valve that Keith is talking about slowed the deceleration of the engine and held the idle high for a few second. The thinking was the exhaust byproducts were cleaner that way. I always considered it a trade off because they were more byproducts because the engine was going faster.

[RustyBucket]

Great typist - aye ! Washed my hands and can't do a thing with them.

I'm trolling the web for info on how to test the gizmo functionality ...

Thanks for the comment.
Cam

[Linda]

Are you trying to go stock or just interested in how it works?
Most owners just get rid of all the smog stuff and plug all the holes.

Linda

[RustyBucket]

FOUND the info on the Gulp Valve on the 510 web site..

http://community.ratsun.net/topic/50115 ... lve/page-2

Now to yank the smog gear off would be nice ...( Sorry Tree Huggers)

[RustyBucket]

The GULP Valve hose connections, 3 total. Two large diameter from the Air pump and a vent hose from both carbs. There is a small diameter hose that connects the GValve to a nib on the backside of the intake manifold

The mystery device a small diameter hose connection to the backside of the original air clearner housing and has the two black electrical leads.
shown in photos.

GULP Valve Hose connect to back of INTAKE Manifold.jpeg

GULP Valve btn Carbs and Airpump.jpg

[spl310]

Good thing that all of mine are pre smog cars. I don't have to learn the proper terminology