looking for advice on where to begin.. the secondaries are not opening on my 85 GSL and because of this, the car is horribly slow and just not much fun t drive. the upside is that the engine runs very well and holds a good idle. i'm looking for some suggestions on what to check or where to begin to get these secondaries working. i recently rebuilt the carb and the secondaries were not opening then either. i can manually open them on the carb when the engine is running and they work just fine. any help would be most appreciated.

 

just wire them up to work manually. is it being slow ur only indication that they're not opening?

 

no..they are just not opening at all..

 

u do know that revving the **** out of it while watching for them to open doesn't work right? the diaphragm may have a small hole in it not allowing the vacuum signal to pull them open.

 

thats correct. they are not opening when i drive the car and depress the accelerator to the floor.

 

i'm considering that the solenoid may have failed. i don't seem to have any vacuum leaks..

 

there aren't any solenoids that would prevent them opening

as others said, you might as well just hook them up mechanically, remove the vacuum box and tie wire around the tabs like in that FAQ link

 

not sure that i want to go with the mechanical secondaries just yet...

 

Are you sure you put the gasket on properly? If it is upside down the secondaries will not get a vacuum signal.

 

alrighty, probably best to check out the vacuum box then, make sure the diaphragm isn't broken and works properly

 

i replaced the diaphram because the old one looked pretty rotten...thats not to say that its any better than the old one but it did sound like it made good vacuum when depressed manually. i'm pretty sure that i installed the gaskets correctly. if i didn't would it run as well as it does...secondaries not withstanding..

 

is the rod that opens up the secondaries connected? there's a picture illustrating what i'm talking about somewhere.

 

i'd like to think so but i'll be in the garage in a few so i'll double check that if anything just o rule it out as a possibility.

 

figured i'd post a video of the issue. in the video i removed the air cleaner lid and took the car around the block. i did this so that you can hear distinctly under load that the primaries are working fine but the secondaries are not. the secondary lever moves freely on both sides of the carb. ignore the maxed out oil pressure and coolant temp gauges. the capacitor wire broke today so the gauges are on the fritz.

 

here is a video of the car accelerating with the air cleaner lid on:

 

Are you familiar with the "teeter totter"? That's the spring loaded rod that sits up on a little perch, but if it is not in position may cause these issues.


Mech secondaries is something you might actually like. When you press down on the gas pedal, at about the halfway point you can feel the increase in spring resistance that let's you know that you are opening the secondaries. Really helps with fuel economy if you can resist the urge to floor it all the time.




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teeter totter, that's the name of that rod that i was talking about, thanks kentetsu

 

yeah i'm familiar with that rod. i'll check and adjust the rod.

 

If you have a hand-held vacuum pump, you can demount and test the secondary diaphragm in it's box pretty easily. Just butt the end of the vacuum hose flush over the second hole from the top.

There's a gasket that goes between it and the carb body, too, that a lot of people miss. Small, four holes in a row.

 

i replaced that gasket when i replaced the diaphram. the old diaphram had black liquid in it...so i snagged a good diaphram off of another carb i had laying around. when i rebuilt the carb, i used a mazda gasket set and replaced all of the gaskets applicable to the rebuild that i did. prob couldnt hurt to test the diaphram with my mityvac..

the rod with the adjuster that rests on an arm is not connected...i will connect it and screw around with the car and see what happens.

 

Be interesting to see the result, as several people of vast experience (including Stirling, IIRC) have held that the throttle sub-return (teeter-totter) has nothing to do with the secondaries opening or not.

Others have disagreed. Loudly.

 

no change when i hooked the teeter totter rod up..secondaries still not working. gonna rebuild another carb i have and try something completely new..i'm out of ideas..

 

You could go right to the master with your question...

www.sterlingmetalworks.com/bymc

 

^^i thought about that but i don;t want to bug the guy. if all else fails though...

 

i ran into something like this with a sterling carb, the idle circuit didn't work, all the passages were clear etc etc, but no fuel. swapping metering blocks fixed it.

so if all the parts to the secondary system work, but they still dont work, then i'd try another carb too