Secondaries don't open in my '86 /w a Roch. Q-Jet

[Brown Betty]

Hey Folks,
I've had my baby for about 16 days now, with about 400km's that I've put on her. I had a couple of problems with the carb(stalling, choke), and I expect that with it having 220k on it. Though, I'm curious to why the secondaries aren't opening

I've read they only open under load, so I've gone 70km/h, and I'll tromp on it, and get nothing

These Q-Jets are foreign to me... There's a green rod, that connects to a vacuum diaphram. The rod's the "metering rod", and the diaphram's the "vacuum break"?

Any tips/ideas?

Here's a pic of my Betty(/w a 305 BTW)...


Thanks,
D

[bobs86silv]

The secondaries are operated manually. With the engine off, crawl on top of the motor, open the flaps on the back of the carb with your finger. Open the throttle all the way with your other hand. First the primaries will open, then you should feel extra resistance, and the secondary flaps at the bottom of the carb will open. If this is happening, they are opening when you drive. It sounds like you have some serious tuning issues that ought to be tended to first. There are lots of adjustments of quadrajets, and they can all adversly affect performance.

robert

[Brown Betty]

Originally Posted by bobs86silv

The secondaries are operated manually. With the engine off, crawl on top of the motor, open the flaps on the back of the carb with your finger. Open the throttle all the way with your other hand. First the primaries will open, then you should feel extra resistance, and the secondary flaps at the bottom of the carb will open. If this is happening, they are opening when you drive. It sounds like you have some serious tuning issues that ought to be tended to first. There are lots of adjustments of quadrajets, and they can all adversly affect performance.

robert

Hey Rob, thanks a lot for your reply.

I did what you said, and the butterflies didn't open up at first. I than looked beside the choke, and there's a "leg" that pivots and it was keeping them closed. With the "leg" out of the way, they opened up perfect

Now what's the purpose of this "leg"?

Thanks,
D

[SSC's76]

Originally Posted by Brown Betty

Hey Rob, thanks a lot for your reply.

I did what you said, and the butterflies didn't open up at first. I than looked beside the choke, and there's a "leg" that pivots and it was keeping them closed. With the "leg" out of the way, they opened up perfect

Now what's the purpose of this "leg"?

Thanks,
D

It's a choke pull off lever, it's supposed to keep the sec's closed when the choke it on/cold. If you can check and make sure the lever has realeased the secondaires when the engine is @ operating temp then they are working.

Idealy you shouldent feel them kick in when you romp the gas there supposed to work progressivly. If you smash the pedal going down the road and the engine get's louder then there working. If you want to feel them kick in you need to adjust the AV tension.

[Brown Betty]

Originally Posted by SSC's76

It's a choke pull off lever, it's supposed to keep the sec's closed when the choke it on/cold. If you can check and make sure the lever has realeased the secondaires when the engine is @ operating temp then they are working.

Idealy you shouldent feel them kick in when you romp the gas there supposed to work progressivly. If you smash the pedal going down the road and the engine get's louder then there working. If you want to feel them kick in you need to adjust the AV tension.

Evening

Thanks for clearing things up... I'll adjust the AV tension tomorrow

D

[Russell]

Welcome to the forum!

Where abouts are you from in Canada? I'm near Edmonton, Alberta

Yeah, I had some issues with my carb's linkage too. I solved it by going to tuned port injection, however, I did fix the no secondaries thing by adjusting the screw on top of the vac canister near the top of the carb. It has a rod that keeps the secondaries closed when its cold, but mine wasn't dissengaging later, so I backed the screw off, and suddenly both my kickdown, and secondaries worked. Caused for a rather large increase in power on the highway, and a rather large decrease in economy as I started to use em more regularly, lol

[Brown Betty]

Originally Posted by Russell

Welcome to the forum!

Where abouts are you from in Canada? I'm near Edmonton, Alberta

Yeah, I had some issues with my carb's linkage too. I solved it by going to tuned port injection, however, I did fix the no secondaries thing by adjusting the screw on top of the vac canister near the top of the carb. It has a rod that keeps the secondaries closed when its cold, but mine wasn't dissengaging later, so I backed the screw off, and suddenly both my kickdown, and secondaries worked. Caused for a rather large increase in power on the highway, and a rather large decrease in economy as I started to use em more regularly, lol

Hey Russell, I'm in Wpg

I know of this screw that you speak of! How much should I back it off?

See you,
D

[Russell]

I backed it off a turn or two I really never did figure out those q-jets. Everything I own is fuel injected now, lol