Mike Markin Posted November 9, 2012 Share Posted November 9, 2012 We got my 23 Model 54 - 6 cylinder operating and took it for a drive. All gears work with good power to all except third gear. After shifting into third the car gets doggy and slows down. It isn't misfiring, just slows to a crawl requiring a downshift into second. Any ideas on what might cause this would be appreciated.ThanksMike Link to comment Share on other sites More sharing options...
Guest WEB 38 Posted November 9, 2012 Share Posted November 9, 2012 Are you using the right shift pattern? The early Buicks are a reverse H Pattern. Bill Link to comment Share on other sites More sharing options...
unimogjohn Posted November 9, 2012 Share Posted November 9, 2012 Mike, just went through the same thing. Mine turned out to be that the heat flap in the little exhaust section was full on. The exhaust could not escape. So I would check that. Also would check the advance to make sure that it full on, mine would gradually creep back to the retard position. And while you are in that area check to see that the points are set correctly. Link to comment Share on other sites More sharing options...
Leif Holmberg Posted November 9, 2012 Share Posted November 9, 2012 If you have the spark plug cover on place just check that the spark plugs not are to long,flash-over is common problem on 1920s Buicks,and that can cause flash-over problem inside the distributor too. Leif in Sweden. Link to comment Share on other sites More sharing options...
Mark Shaw Posted November 9, 2012 Share Posted November 9, 2012 Good suggetions here... I also suggest you check for fuel delivery. If your gas cap is not vented, and/or your fuel system has any air leaks, your vacuum tank will not be able to supply enough fuel to sustain the engine when pulling at higher speeds. Link to comment Share on other sites More sharing options...
dibarlaw Posted November 11, 2012 Share Posted November 11, 2012 Mike : Thanks for posting the question as my 1925-25 is doing the same thing.Larry Link to comment Share on other sites More sharing options...
Brian_Heil Posted November 11, 2012 Share Posted November 11, 2012 Check the fuel screens too in the fuel tank, Stewart tank and at the carb. inlet for being plugged / low flow. Float function too in carb., under high demand the float needs to drop and let lots of fuel in.Also, make sure the heat control valve stays where you want it / put it. It can move if the linkage is rigged wrong, loose or has a weak spring under gas pressure at speed. Link to comment Share on other sites More sharing options...
Leif Holmberg Posted November 11, 2012 Share Posted November 11, 2012 There is another problem with those Buicks too , and that`s the Riser assembly,this is conected to inlet and exhaust manifold as well as to the carburetor,inside this riser is a thin tube that can cause truble becuse of rust hole.And exhuset goes to the inlet manifold.Leif in Sweden. Link to comment Share on other sites More sharing options...
Brian_Heil Posted November 11, 2012 Share Posted November 11, 2012 Leif is 100% correct, but that inner, vertical tube design started in '24 on the six cylinder. I (and a whole bunch of other 'helpers')watched Mark Shaw fix this on his '24 on the show field in Minnesota at the National Meet a few years back. What was it, 102 F outside (39C)? Lord it was hot.But again, those with a '24, that would be the #1 thing to look at. Link to comment Share on other sites More sharing options...
Leif Holmberg Posted November 11, 2012 Share Posted November 11, 2012 Thanks Brian,i didn`t know that 23 6cyl.was different from later 20s.Leif in Sweden. Link to comment Share on other sites More sharing options...
Brian_Heil Posted November 12, 2012 Share Posted November 12, 2012 Ha, Leif. You make me chuckle. I live 18 miles South of Flint and you still know 1000% more than me about these old Buicks! And I'm pretty certain you have to read and translate everything too (which you also do very well). Link to comment Share on other sites More sharing options...
Mike Markin Posted November 13, 2012 Author Share Posted November 13, 2012 Thanks, everyone. Now I have a good punch list to go through. I hope to have this worked out before the snow flies, which is soon in Wisconsin.Mike Link to comment Share on other sites More sharing options...
dibarlaw Posted November 18, 2012 Share Posted November 18, 2012 Mike : I responded to your other post but I believed I solved my 25's "doggieness in 3rd". I could move the distributor about .060 from side to side also the shaft was just as sloppy. I bought a cast iron 1924 ? distributor at an auction last week and rebuilt it. Still had .003 tolerance on the shaft. When I pulled my die cast distributor there was a steel sleevepressed over the lower casting with no provision to lube the shaft or it's bearing. (The grease I put into the fitting prior went nowhere). Close to .015 side play. The lower shaft casting was broken from the body. Also the cetrifugal advance plate was missing a spring and one not connected! It is amazing that I could get it to run at all! Dropped the rebulit unit in and retimed and now all is well on the ignition side! Larry DiBarry Link to comment Share on other sites More sharing options...
Mark Shaw Posted November 19, 2012 Share Posted November 19, 2012 Mike, Brian is correct... I did replace the heat riser tube with a piece of exhaust tubing. We went to a local muffler shop where we removed the old rusted tube and pressed a piece of aluninized exhaust tubing into the heat riser casting. My buddy Rob S. did the same thing to his when he got home (just for peace of mind). Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now