Idle RPMs

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Jim Beam
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Idle RPMs

#1 Post by Jim Beam » Mon Jul 09, 2018 7:24 pm

1963B Coupe Normal; running Weber 40s with Bosch 050 distributor. Suddenly the idle speed reduced itself to about 300 RPMs. Motor quits at that RPM. Wondering is there is a relatively simple adjustment to be made to increase the idle speed to around 750 RPMs?

Dick Weiss
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Re: Idle RPMs

#2 Post by Dick Weiss » Mon Jul 09, 2018 7:41 pm

Each carb has an stop screw which adjusts the carb's idle RPM; For an balanced idle, you must use a Unisyn, or Sychronometer (gage).

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Doug McDonnell
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Re: Idle RPMs

#3 Post by Doug McDonnell » Mon Jul 09, 2018 8:11 pm

But if everything was fine with stable idle and you suddenly developed this then there is a reason to be found. Distributor plate was sticking for a long time and finally went back to base? Doubt it. Maybe a partially clogged idle jet? More history would help.
1965 356C There is never enough time to do it right, but always enough time to do it over.

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neilbardsley
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Re: Idle RPMs

#4 Post by neilbardsley » Tue Jul 10, 2018 6:16 am


Tim Berardelli
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Re: Idle RPMs

#5 Post by Tim Berardelli » Tue Jul 10, 2018 8:21 am

Jim,

Check your dwell-as the rubbing block on the points wears the dwell increases and the timing becomes retarded-a .004 reduction in point gap will change the timing by 3 degrees.

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Ron LaDow
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Re: Idle RPMs

#6 Post by Ron LaDow » Tue Jul 10, 2018 9:36 am

I keep beating this horse, but it's sill not dead:
DO NOT adjust the carbs first.
Do a complete tune up in the proper sequence, and adjust the carbs to suit what the specific values (valves and ignition) want.
Ron LaDow
www.precisionmatters.biz

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neilbardsley
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Re: Idle RPMs

#7 Post by neilbardsley » Wed Jul 11, 2018 4:45 am

Ron LaDow wrote:I keep beating this horse, but it's sill not dead:
DO NOT adjust the carbs first.
Do a complete tune up in the proper sequence, and adjust the carbs to suit what the specific values (valves and ignition) want.
That is what the link I posted suggests :)

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Re: Idle RPMs

#8 Post by Tim Berardelli » Fri Jul 13, 2018 4:58 pm

Jim,

Did you ever solve your low idle problem?

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Re: Idle RPMs

#9 Post by Jim Beam » Sat Jul 14, 2018 7:42 pm

Thanks for the responses. Car has been sitting in the garage and I haven't had time to attend to it. I really do not have the skills and am attempting to get it into my wrench for a couple of issues, the low idle RPM being one of them. In the meantime, I am wondering whether I can adjust the carb linkage to accomplish a higher idle RPM? This would be only a temp fix until the issue can be addressed further. Thanks again.

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Ron LaDow
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Re: Idle RPMs

#10 Post by Ron LaDow » Sat Jul 14, 2018 10:06 pm

Jim,
If you bandaid it, it just makes the proper adjustments more difficult. Why not just get it to him and let him to the correct process?
Ron LaDow
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Wes Bender
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Re: Idle RPMs

#11 Post by Wes Bender » Sat Jul 14, 2018 10:18 pm

+1 on what Ron says. You would be adding a complication if you adjusted the linkage without knowing that it was the problem. You indicated the idle suddenly dropped to the 300 range. I'd let the wrench know everything you've told us and let him find out what took place. I'm assuming that your wrench is well qualified in these fine cars.
Some days it just isn’t worth the hassle of chewing through the restraints......

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