Still Having Accel. Probs. ?????
10-05-02, 02:46 AM
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Still Having Accel. Probs. ?????
Ok If you haven't read my previous post I'm having accel. problems. I've changed plugs, fuel filter, & the pump, plus I got a Mazda guy to come out. He got it to idle smoother, plugged a hose (the shutter solenoid I think), adjusted the mixture screw, checked the compression, checked for vac. leaks, and set the timing. Unfortunately I don't have the money to pay him what he desrves, and he did this a mere $20. This of course didn't fix the problem. Which is, when I accelerate I have to floor it to get any serious power. Plus if while accelerating I let off the least bit I lose most all of my power. The only way to get it to gain the power back is to either let all the off and floor it again, or push in the clutch rev it up and then drop the clutch while staying on the gas. The only fuel thing I have yet to do is clean the primary jets. If thats not the problem is there any new suggestions, eg. exhaust, seals, and ect............... I'm just stumped.
10-05-02, 07:20 AM
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Nikki-Modder Rex-Rodder
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A carb rebuild is definitely in order. My guess is that your secondary diaphragm is as tough as old leather and needs replaceing; Or, there is a seal problem in the housing.
Here's how it works:
It's the box that's at the front passenger side of the carb. Inside is a big diaphragm. On the outside side of the diaphragm is a spring that keeps a constant bit of tension of the diaphragm. On the center of the diaphragm is a metal disc, and that's attached to the linkage that moves the secondary throttle shaft. It's the only thing that does move that shaft.
On the inside side of that diaphragm, the housing is connected to the carb - screwed on. But there is a a hole (circuit) that runs to the front primary ventury (barrel). If you look into the front small venturi of the carb, way down in you'll notice a hole where the other one does'nt have one.
When the engine is under alot of load, or when you rev it, there is alot of air flowing thru the carb. What it creates is reffered to as vacuum, and it sucks out the air in the that circuit going to the diaphragm housing. Sucks out that air, too, and the diaphragm begins to move against the tension of the spring - And your secondaries begin to open.
You can see that if the diaphragm is old and stale it would be like having a really strong spring in there - too strong. And you can see that if the gasket around the housing cover is leaking, than the diaphragm does'nt get 'sucked' inwards.
You should also check the linkage underneath to see if there is an obstruction.
There's another thing- in order for any of this business to work at all, the primaries need to be opened a certain amount. There is a spring wound around the secondary throttle shaft on the other side of the carb with linkages to prevent them from opening at all untill the primaries are opened up alot. That's when the spring tension on that shaft spring is loosened up.
And don't expect to see your secondaries open when you're reving it in the drive way.
Don't throw money that you already said you don't have at this yet. Check the vacuum diaphragm box. Try removing the spring. See if there is a good clean seal all the way around the box.
Read "Carb Crap...Nikki Mods" in the archives.
People say it's wordy, but it'll explain all of it.
Here's how it works:
It's the box that's at the front passenger side of the carb. Inside is a big diaphragm. On the outside side of the diaphragm is a spring that keeps a constant bit of tension of the diaphragm. On the center of the diaphragm is a metal disc, and that's attached to the linkage that moves the secondary throttle shaft. It's the only thing that does move that shaft.
On the inside side of that diaphragm, the housing is connected to the carb - screwed on. But there is a a hole (circuit) that runs to the front primary ventury (barrel). If you look into the front small venturi of the carb, way down in you'll notice a hole where the other one does'nt have one.
When the engine is under alot of load, or when you rev it, there is alot of air flowing thru the carb. What it creates is reffered to as vacuum, and it sucks out the air in the that circuit going to the diaphragm housing. Sucks out that air, too, and the diaphragm begins to move against the tension of the spring - And your secondaries begin to open.
You can see that if the diaphragm is old and stale it would be like having a really strong spring in there - too strong. And you can see that if the gasket around the housing cover is leaking, than the diaphragm does'nt get 'sucked' inwards.
You should also check the linkage underneath to see if there is an obstruction.
There's another thing- in order for any of this business to work at all, the primaries need to be opened a certain amount. There is a spring wound around the secondary throttle shaft on the other side of the carb with linkages to prevent them from opening at all untill the primaries are opened up alot. That's when the spring tension on that shaft spring is loosened up.
And don't expect to see your secondaries open when you're reving it in the drive way.
Don't throw money that you already said you don't have at this yet. Check the vacuum diaphragm box. Try removing the spring. See if there is a good clean seal all the way around the box.
Read "Carb Crap...Nikki Mods" in the archives.
People say it's wordy, but it'll explain all of it.
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