1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

dash pot question

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Old Feb 28, 2007 | 05:54 AM
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dash pot question

can a sticking dash pot cause hard starting and a rough idle? (yes i searched)
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Old Feb 28, 2007 | 06:11 AM
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From: St Joe MO
Dash pot slows the closing of the throttle plates on decel. Is it sticking and not allowing the plates to return to idle position, or is it just really slow? I suppose it could make staring harder, particularly when cold as it would lean out the mixture. Same might be said for rough idle, it would be leaner also. You could loosen the nut and back the dash pot off and see if that solves the problem. Be sure to count the # of turns so you can return the dash to it's original position.
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Old Feb 28, 2007 | 07:57 PM
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well, the dash pot melted...had an engine fire and that was one part of the carb that didn't make it. everything has been repaired or replaced except the dash pot. the rod does not move at all. i have excellent and smooth power in the upper rev range(3500rpm or above). the first time the car has ran in six years was less than a wek ago. i've never driven the car. i'm just trying to make my new gem road worthy. i changed one ignitor(leading), one coil(leading), newer plugs and wires(good shelf stock), and removed and cleaned the carb. the car sometimes starts right up and other times, it takes a good cranking. with the plugs out, i get three even pulses from each rotor and the engine feels very strong. i have a new fuel filter that needs to go on and new plugs that'll be in tomorrow at napa(NGK). i'm in hopes that after the new plugs and the fuel filter, the engine will start running better. once i bleed the brakes(new RR caliper and pads on both sides were put on today) i can get the car up to the gas station and put more gas in the tank. the gas in the tank is new(only two gallons worth). i got the old crap out of there. so, i'm wondering if the dash pot could play a factor in my problems. the rod is melted.
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Old Feb 28, 2007 | 09:03 PM
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From: St Joe MO
Yeah, it may be part of you problem. How hot did the rest of the carb get? It may have internal damage. You can remove the dash pot and run the carb with out it. PM me if you need a new DP.
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Old Feb 28, 2007 | 09:15 PM
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i'm not sure of the internal condition of the carb. i didnt have too much time to inspect it, as it was dark and everything was frozen and my fingers were numb. i've never rebuilt an rx-7 carb. i do have a carb rebuild kit in the GSL's passenger storage bin. i've thought about rebuilding the carb but i'm not sure when i'll have the time to get into it. i have the mazda carb service manual. its really a helpful tool. thank you for the offer on the dash pot. if i can't find one on one of my spare carbs i'll be sure to contact you!
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Old Feb 28, 2007 | 09:18 PM
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just rip it out, you dont need it. all it does is allows the car come back down to idle slower. which makes it sound bad, but if you have an unstable idle, the car may come down too fast, and stall. so weigh your choices...
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Old Feb 28, 2007 | 10:23 PM
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Considering everything that the car has been through my guess is the problem is something besides the dashpot.

If you're lucky some fresh gas and fuel system cleaner might get the carb working again, if you're not lucky something else probably melted in the heat.

Life is better without the dashpot anyway, your RPM will drop faster when you go to upshift and you'll be able to shift smoother. As a bonus, sometimes you'll backfire.
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Old Mar 1, 2007 | 04:57 AM
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i did repair or replace everything that was burnt with the exception of what looks to be two a/c wires the snake behind the carb and the reverse ligting wiring. the reverse lights still work just fine but i still want to get in there and cut the old wiring out and rewire any burnt sections of wire. i'll keep the dash pot for now because i want a 100% bone stock 7 to just cruise in. originally thats what my Leather Sport was for but i dont like racking up miles on it. thats why i bought this low mileage(85K) 82 GSL.
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Old Mar 1, 2007 | 05:39 AM
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From: St Joe MO
If you need the carb rebuilt and don't feel up to doing it yourself, PM me.
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Old Mar 3, 2007 | 05:29 AM
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thanks for the offer! i replaced the plugs with a set of new NGK's and replaced the fuel filter and she's running TONS better!! after i replace the front brakes(rear are done) and bleed the system, i'll take the ol' beast for a drive and finish working out the bugs.
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