300 V8 slow to start when sitting

Hey everyone,<P>I am a lover of old cars and a decent "do it yourself" type person, but my mechanical knowledge is rather limited so I was hoping to get some input from everyone. I'm gradually learning! <P>I've got a '65 Skylark with a 300ci V8. If it sits more than 24 hours or so, it takes a long time to start it. I have to crank the engine for about 10 seconds while pumping the gas pedal until I hear any gas at all hitting the engine (it starts to "catch"). Of course before cranking I put the pedal to the floor to set the choke. However it won't even start like this, I've got my system down now -- after the 10 seconds of pedal pumping and when it starts to catch, I stop. I set the auto choke again, and then I can get it running within a few seconds of cranking. Oh, I can also get it started very quickly if I take off the air cleaner and dump some gas directly in the carb!<P>Could it be the choke? How do I check/adjust the choke? My service manual is not very descriptive about this. I know it's on the carb but after that I'm lost!<P>Yet it doesn't seem like it is the choke. The engine will start okay when it has been run in the past 24 hours but still cold.<P>It only has the starting problem when it has been sitting for a couple days or more. So I'm thinking the gas is evaporating out of the carburetor and my pedal pumping is needed to get the gas back up to the carb. But should it take so long? Could it be a fuel line or fuel pump problem? I am going to check the fuel filter and such. How do I test for a faulty fuel pump?<P>Once the car is started and warmed up, it runs very well. The only other thing that I am wondering about is a slight delay when I give it some gas, usually from a stop. It seems to take a second for the engine to react to the gas pedal. Although it is much much more noticeable when the engine is not warmed up completely. Is this normal for a carburetored car (the only other one I've ever owned was a VW Beetle)? Or could this also be a fuel problem?<P>What about the ignition, any chance something there could be part of the problem? When I get a chance I'm going to examine all the sparkplugs, distributor, etc.<P>Anyone have any recommendation for good performance sparkplugs for my 300?<P>Thanks for reading this long post!<P>Carl

Hi Carl!<P>The *gasp* that you feel when hitting the throttle is familiar... my new (to me) '70 Skylark had the same problem.<P>This weekend I replaced the entire ignition system in my car:<P>Coil<BR>Distributor Cap<BR>Rotor<BR>Plug Wires<BR>Spark Plugs<P>I also installed a Pertronix Ignitor in place of the points and condenser.<P>After some initial minor trouble, the car runs like a different animal! The hesitation from idle is quite nearly gone, even though my carburetor is screaming for a rebuild kit. The car drives very well in the morning now, needing only a minute or two warm up before driving away.<P>Long ago someone gave me sage advice... always go after the ignition system first. Get it working perfectly, then go after the fuel system. By nature, carburetors are not prone to go out of adjustment. At the age of our cars however, gaskets can get brittle and leaky, and deposits can build inside the smallest passages, compromising fuel delivery. You probably need to rebuild your carburetor, as do I, but starting with the ignition might help your situation.<P>By the way, it sounds like your choke is working. Try this to be certain:<P>Remove the air cleaner and pull the throttle open to set the fast idle cam and get the choke butterfly closed. You should easily see the butterfly close on top of the carburetor body. If you observe this, the choke is working.<P>My two cents...<P>Matthew<p>[This message has been edited by 67GSCalif (edited 09-25-2000).]

It has all the qualities of an accelerator pump problem. That's in the carb. Get yourself a rebuilding kit and have at it. The kit should have all the new gaskets you require. Just read the instructions first. New plugs will probably help, but won't cure the problem. <P>------------------<BR>George C. Thomas<BR>70 GS 455 12.teens<BR>86 GN Low 13's/ high 12's

Your hesitation would be the "Accelerator Pump" in the Carb.<BR>Sounds like rebuild time.<BR>Your Choke and Ignition sound fine.<BR>The Fuel Pump must be OK since it does run.<BR>Try Rebuilding the Carb. and see if that doesn't fix both of your problems.<BR>The Gas must be leaking, boiling or evaporating out, leaking or boiling being the most plausible.<BR>Make sure the Carb. isn't cracked during the rebuild.<BR>Does your car run hot? Mabey Its boiling out after you shut it off.<BR>Good luck.<BR>Dale

[Wildcat65]

Another thing to check is your fuel line. I had the same problems or similar with my Special Wagon. I found out there was a pinhole in the line that allowed the gas in the line to drain out-1 drop at a time. Made it seem like forever turning the engine over to start. I never would have found it if I had not installed a electric fuel pump to drain the tank- all the pressure and the gas just came squirting out, and I had my moment of clarity! So, che hoses and lines, if you smell gas, be suspicious of leaky line! <P>------------------<BR>Ted Nagel<BR>65 WildcatConvSuperWcat<BR>65 WildcatAutoSuperWcat<BR>65 Wildcat4spdSuperWcat<BR>65 Riviera Wildcat 445<BR>65 Special Wagon 455<BR>70 GS Stage1 4speed

How abou....Don't pump the gas while cranking! That is an old rule, pump then hold that gas at about half or less then turn key. The comment on putting gas in the carb is a dead givaway to a fuel pump problem though. Forget the electronic ign stuff, the car worked in 1965, it should now. If it runs good and you want to improve it, by all means try electronic ign., but not when you are trying to find a problem. <P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.

Thanks for all the information, I will try:<BR><p><BR>-A different starting method (not pumping while cranking)<p><BR>-Checking the fuel line for leaks<p><BR>-Examination/overhaul of ignition system<p><BR>-Checking/rebuilding the carb/accelerator pump<P>MartinSr, I understand your feelings about electronic ignition. First of all, I don't expect that to fix the problem (this post is unrelated)... I am doing it for peace of mind and the slight mileage/performance increase. I am a guy who cringes at anything that isn't stock, but for some reason I think electronic ignition is probably the one component that makes sense. This is not a show car; if it was, I'd keep the points. I think for a potential daily driver, it is justified.

[GSMAG]

I agree with Martin Sr., sounds like the fuel pump is bad, allowing fuel to drain back down from the carb. Obviously it won't siphon out of the bowl, but if the line from the pump is dry, it'll take a few seconds to get fresh fuel to the carb.<P>Mike

carlivar, I have a '65 Skylark and the best thing I ever did to it as far as drivability is to add a hot air exchange off a later model. If you search the achives you may find my posts on the how-to. I believe in originality when it makes sense. On a daily driver you want everything that will make it perform and be safe. Not to say everything goes out the window, my '65 looks to all as an original, but I do have later finned aluminum drums, an HEI and the hot air exchange and I will tell you NOTHING made me happier than the Hot air exchange, It starts and runs great with out the "cold blooded" mornings they are famous for (imfamous?). <P>I didn't really mean ONLY a fuel pump problem, it is simply a fuel delivery problem. it could be the accelerator pump, just as easily as the fuel pump. <P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.

[YellowLark]

I solved my "hard starting after sitting for a week or more" problem by installing an elecric fuel pump in front of the tank to prime the carb.<P>However, I also have a noise problem with that pump, as noted in another thread.<P>My advice would be a install an electric pump and switch it on to the fill the carb before turnng the starter.<BR><P>------------------<BR>

[John Chapman]

YellowLark,<P>Sounds like a solution. Recip engine airplanes have been using the electric aux fuel pump solution for decades to solve the same set of problems (dry bowl, vapor lock, low pressure/volume at cranking speeds).<P>You might even consider using a momentary switch so you don't inadvertently leave the pump on for extended periods.<P>------------------<BR>John Chapman<BR>BCA 35894<BR>1965 Skylark Convertible (Some Assembly Required)<BR> jmchapman@aol.com