aussiecowboy Posted June 5, 2015 Share Posted June 5, 2015 I have a 1935 Pontiac 6 cylinder with a W1 tagged as a 314S. This car was a barn find and hadn't been run since 1966. I got the car running without dramas including buying a kit and rebuilding the carb. It now starts fairly easily and feels good at low revs but in the mid and higher end of the rev range the car surges and bucks badly, pulling the choke on smooths it out again and it gets down the road quite well. I have pulled the carb down twice more and can't see anything wrong. Float is adjusted to 3/8" as per the factory manual and it doesn't have fuel inside the float as far as I can tell. I'm starting to think the main jet included with my kit is wrong and the metering rod is now way out of adjustment causing it to lean out. When I stripped the carb I was unable to remove the plug at the bottom of the accelerator pump passage, someone has glued it in place but the pump is delivering a good shot of fuel so I wasn't too concerned. It is also worth noting that the idle mixture screw can be turned all the way in without stalling the engine so I assume there is some leakage at the throttle shaft, but I wouldn't think it bad enough to lean the engine out that severely. Fuel pump isn't the issue, I installed an external pump running from a fuel can and it made no difference. Any advice here would be appreciated. I'd be happy to buy another kit if I can find one that is definitely correct and a metering rod gauge would be very handy indeed. I should mention that I'm in Australia. 1 Link to comment Share on other sites More sharing options...
robert b Posted June 5, 2015 Share Posted June 5, 2015 I will have a look tomorrow and see what specs are for the carb and what gauge rod it to be used and see if I have one . Bob Link to comment Share on other sites More sharing options...
carbking Posted June 5, 2015 Share Posted June 5, 2015 The metering jet is the two-stage type, with 3 number 67 constant feeds, and a number 44 main orifice. (Drill sizes). The metering rod is a three-stage. Low vacuum 0.040, mid-range 0.066, and high vacuum 0.074. The metering rod adjustment gauge is T109-26. While it is possible you have the wrong main jet, or metering rod, or the metering rod is out of adjustment; MUCH MORE LIKELY on a W-1 that there is wear in the linkage connecting the throttle with the metering rod. The round hole in the bracket wears to an oval shape, a groove wears in the rod, and this causes the geometry of the metering rod to be out of synchronization with the throttle EVEN WHEN THE METERING ROD IS PERFECTLY ADJUSTED. If this condition is present, the solution is to replace the bracket and throttle connecting rod. Jon. Link to comment Share on other sites More sharing options...
Guest Al Brass Posted June 5, 2015 Share Posted June 5, 2015 I too think the metering rod is likely to be the problem. Try lifting it a little and see if you can improve it. RegardsAl Link to comment Share on other sites More sharing options...
aussiecowboy Posted June 6, 2015 Author Share Posted June 6, 2015 Thanks for the replies gentlemen, great information and very much appreciated. I have a couple of "core" W1 carbs, I will check the brackets and connecting rods to find the best set and will also try to locate the correct gauge. Are the brackets and connecting rods the same for all W1 variants or do I need to obtain them from another 314? Also, the rebuild kit came with 2 float bowl cover gaskets and I can't work out why? Link to comment Share on other sites More sharing options...
carbking Posted June 6, 2015 Share Posted June 6, 2015 Cowboy - Carter made 128 different W-1 carbs. From memory (generally a very bad idea ) there are at least 4 different bowl cover gaskets, at least 3 different brackets, and at least 2 different throttle connector rods. Jon. Link to comment Share on other sites More sharing options...
aussiecowboy Posted June 6, 2015 Author Share Posted June 6, 2015 Fingers crossed that one of my core carbs has the right pieces then, otherwise it will be ebay time! Link to comment Share on other sites More sharing options...
Guest Al Brass Posted June 6, 2015 Share Posted June 6, 2015 Cowboy,The connecting rod can be bent to achieve the correct dimension during set-up. Interchanging them is not a good idea. The metering rod referred to is not a connecting rod. RegardsAl Link to comment Share on other sites More sharing options...
aussiecowboy Posted June 7, 2015 Author Share Posted June 7, 2015 I realise that the metering rod and connecting rod are different beasts. I can see how it would be easy to bend the connecting rod to the correct dimension, but that assumes it doesn't have grooves worn in it's ends. If this is the case then replacement is almost unavoidable, as carbking suggests above. Link to comment Share on other sites More sharing options...
philipj Posted December 30, 2020 Share Posted December 30, 2020 Does anyone know what is the correct metering rod gauge for a Carter W-1 (391-S)? Thank you. Link to comment Share on other sites More sharing options...
hwellens Posted December 31, 2020 Share Posted December 31, 2020 Some info: Due to size limits I will add 2 of the 4 pages and the other 2 later: Link to comment Share on other sites More sharing options...
hwellens Posted December 31, 2020 Share Posted December 31, 2020 Here are the other 2 pages: Link to comment Share on other sites More sharing options...
hwellens Posted December 31, 2020 Share Posted December 31, 2020 (edited) 2 hours ago, philipj said: Does anyone know what is the correct metering rod gauge for a Carter W-1 (391-S)? Thank you. If used on a 38 Chevy the metering rod Gauge is T109-25 Edited December 31, 2020 by hwellens (see edit history) Link to comment Share on other sites More sharing options...
philipj Posted February 3, 2021 Share Posted February 3, 2021 Hello there, thank you very much for information and the extra parts pages... Very useful! Link to comment Share on other sites More sharing options...
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