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CaptRandy

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When 66 Sprite has warmed up to 170 and taking out for a ride I have a hesitation in acceleration. Am thinking of accelerator pumps but not sure if this is place to start. Pump pedal a few times and the car accelerates fine but just a sort of hesitation when I first let clutch out. Any other ideas of start place? Do not know if and when the carbs were ever rebuilt.
 
66 sprite should have SU's. No actual accelerator pump. That function (transient fuel/air enrichment during initial phase of acceleration) is carried out by the dampers. Do you have oil in the dampers of appropriate weight and level?
 
Make sure there is oil in the carb dampers. Little Black Cap on top of the SU's. Lots of things that can be used anyhing from ATF to 3 in One oil. Viscosity affects how quickly carbs open up.
 
Do you have the standard SU carbs? If so, they don't have accelerator pumps. I'd suggest you first check ignition timing, plugs and points and then make sure your carburetter dashpots have oil in them.
 
Thanks guys, Have the SU's but used to GM cars that is where accelerator pumps idea came from. Will check to be sure that the "sump"of each carb is full. I do have some 3 in 1 and will add as needed. Any problem if the PO used a different oil? I was about 40 degrees out on Sunday when I went out.
Will pull out timing light to check as well as dwell meter. Thanks again for some direction. 1971 was last year had a AH. Too much travel in USCG to have kept it.
 
Randy, Not knowing what is in there you might consider sucking out the old but usually the oil gets sucked into the engine over time that's why they need to be topped up on a regular basis. Good luck with standing on your head to read the timing light. Advanced Distributors (NFI) sells a remote timing pointer kit for 1275's. Something like $20.
 
The higher the viscosity the richer the mixture on acceleration
Try 30 wt motor oil if ignition timing and points are good (and no vacuum leaks)
 
This is admittedly a little off the wall--but 170 degrees strikes me as a little cool, especially for a 1275 where the temperature (if I remember correctly) is measured at the head. If you are using a 165 degree thermostat, you might want to try a 185.

Even here in SoCal, I had problems with hesitation in my Bugeye on cool days. I had a 165F thermostat and an electric fan, running continuously, installed by the PO. I removed the fan and all was well. As a former PA resident (grew up in Philadelphia), I can attest that winters there are indeed a tad cooler than here.

Beyond that, check the usual suspects--carb damper oil, carb adjustment, distributor timing and advance, even valve adjustment--just about anything that's off can give you hesitation problems.
 
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