Vaccuum Secondaries...not opening????

[swervin ervin]

The port with the yellow cap is what normally went to the charcoal canister. It could be considered the bowl vent I guess, but it's not meant to be vented to the air. It does need to be open though. If you keep it capped off, it could cause problems with not being able to vent gas vapors.

I see his hose going to the PCV port. It's under the fuel inlet where they have always been. Look again at the second group of pics he posted. Look real close at the first pic in this group.

[TwinTurbo]

how does not having a PCV gum up your motor? Just breathers work fine, no brethers won't work because you will blow out your dipsstick because of blowby. PCV is nice to keep fumes from turning the oil acid but it also makes a mess of the intake manifold and the carb. EGR makes a mess of the intake too.

I like brethers or an exh. evac. system like I have on my other engine.

[Paso76GMCstepper]

My PCV valve is brand new and working properly. I even put a new Grommet in. I have a question about the line with the yellow cap. If not plugged and it should be able to vent what would I put there. Thanks for all the help I always learn something from you guys.

[swervin ervin]

The air valve dampener/choke pulloff is a critical part of the secondaries operating properly. The spring is a helper and controls them somewhat. I have my spring adjusted to 1/8 turn from zero tension, to where stock it is set to 7/8's of a turn. 1/8 is just enough to keep the AV's closed. Power comes from the dampener. If this is not working properly or even hooked up, they will slam open and you will have the infamous bog. The dampener lets them come in in a more controlled or slower manner to help catch up with the fuel. Something the spring won't do. Of course you have to tune the secondary hanger and rods too. In order to have a lot of air, you have to increase the amount of fuel.

On the vent port, I think just leaving it open would be OK. I've never tried it, but I doubt any gas would come out. Maybe if you off roaded or made a lot of real hard stops. But, it does need some kind of bowl vent or else vapors will probably increase fuel level and may seep raw gas into the intake. It might even go as far as to cause vapor lock. We all know a hot carb/fuel mix is not a good thing. When the fuel percolates it needs a way to let the rising pressure to escape.

[Destructo]

It seems to be pretty dang common that these carbs don't have those linkages on them, I wonder why they are removed or maybe they just fall off? I know I have 3 Q-Jets laying around and none of them have the rod on them, I don't understand why somebody would want to remove them. Oh well.

[swervin ervin]

I believe why you see so many missing is clueless folks thinking they cause problems. Not knowing any better they think if they take the linkage off it will let the secondaries open faster. This is true, but at the cost of a big bog. Then they find out there is an adjustable AV spring and overtighten it to overcome the mess they've made by removing the linkage. Another thing is going to the junkyard to get used Q-jets. A ton of these things have had the linkage rods removed because folks like us need them to replace the ones somebody else took off.

[screwballl]

that sounds like a similiar problem that i am having with my 76GMC c1500 w/ 350, stock rochester 4bbl carb... when i floor it it doesnt seem to get that extra boost from the secondaries and sometimes bogs... i will have to go through mine and see what i can see and do based on the info here.

edit: ok i got 2 pix, nothing strange on the drivers side, but on the passengers side, the vacuum advance only pushes forward and seems to operate the primary whereas in order for the secondary to open, it turns to the back and the vacuum only travels in one direction (pulls to the front)... theres no other links or vacuum connections connected to the secondary that i have found unless it is internal. it doesnt matter if the engine is warm cold or ignored, the secondary does not seem to have a working link...

[Destructo]

Mine runs pretty good until I get to the secondaries then I have some bogging and it tends to run rich for a little bit. If from a stop I wanna go fast it works better not to floor it instantly, works better if I just open primaries but not secondaries and slowly roll into the seondaries, mine doesn't have the rod to control the plate at the top.

[screwballl]

yeah i have to start with about 1/2 throttle then slowly floor it to get decent acceleration, otherwise it just feels like its holding back....

[SanitysBane]

i don't have the butterfly on for the choke, i have no problems gunning it from a stand still, unless its cold

[screwballl]

ok i took mine for a test drive since last post(s)...
i took the air cleaner off so i could hear the secondary opening up...
i drove it 10 miles or so to pay a bill, several times gunned it from 30-45 mph up to at least 60mph and the secondary would not open up...
shut of truck, ran inside for less than 5 minutes, when i came back out and on my way home, did the exact same thing and several times they opened up with their loud throaty roar, so i decided try something else. Stopped at the gas station to get something to drink and talked with a friend for 10-15 minutes, then drove it back home and they opened up again both times that i gassed it. So they are opening up but it still feels like theres some hesitation at first...

as a side note, on the way home some little tricked out Accord thought he would race me at the front of the pack of cars, they opened up nicely and went from 30mph to 70 in no time while the ricer sounded like he was about to blow somehting trying to keep up with me his loud ass muffler gave it away that his car was wrapped up well past 6k rpm... when he finally caught up with me a few miles down the road he was just looking at my truck with a puzzled look




this is the side he saw for a short while:



it may not be the best looking truck and may not always run the best but for a worn out tired stock 350, he still holds up when i want him to

[Destructo]

I bet you wouldn't be able to keep up with my daily driver, and its all stock. MMM, 1.8L Turbo! My beetle does 0-60 in 7.6 seconds stock, I think that is with an automatic, mine is a 5 spd, pulls a lot harder than my truck ever has hehe.

[screwballl]

maybe not Destructo but for a tired truck he does damn well

[TwinTurbo]

Is that a turbo S 1.8? I thought they only came with a 6 speed manual, no auto available on the turbo. As for the 0-60 time, you sure you're not a second off?? Should be somewhere around 8,5 secs.

[Destructo]

no, mine is a normal turbo 1.8Tm 150HP, 163 torque stock. 0-60 on a stock 1.8T (non s-model) is 7.6 seconds from what I have seen. I have a G-tech so maybe when I get it back from the dealer i'll try it out. It pulls pretty damn hard though.

And VW makes (or did) a normal 1.8 turbo (5 speed), turbo s model (6 speed, 6 speed auto available soon I believe), and of course the wimpy 2.0 N/A model and a Turbo Diesel model. This is in the states anyway, if your in another country I don't know, and I don't know what models are available in 2004 only.

[screwballl]

yes he is in Netherlands, Dest and i have seen cases of low elevation your car getting low sevens

[TwinTurbo]

A 150 hp beetle will not do 0-60 in 7.6

The Netherlands is about the lowest elevatoin you will find anywhere, we're mostly BELOW sealevel and I can assure you it will not do 0-60 in that time

I know someone who has one and my coupe fiat is faster and it's not 8 sec fast