TFB3

Just a thought... might it be that your steering column lock hasn't been unlocked?

Mario, Your work is impressive! I've been told I may need to replace the venturi on my 1928 Buick Standard. It's got a T3 Marvel "10-103". The car is new to me, so this may be an obvious question, but how can I tell which venturi I need? Do I have to take it all apart and find a number stamped on it or is there an easier way? Thanks! Tom

Quick Update: I'm copying this update from another post I just made because it's relevant for this discussion too. I reduced the idle from 700 to 360 and retarded the timing a bit more. Now for the first time, the spark lever produces a noticeable RPM difference from top to bottom. Using a timing light, I can see that I'm at 22° / 460 rpm at full advance and 0° / 360 rpm at full retard. My vacuum has dropped three pounds to 16 lbs; undoubtedly the result of dropping the idle from the previous 700 rpm. The new lower idle definitely helps get into gear while stopped, but it still protests every so often when hot, so I'll probably try the 2:1 mix of Lucas 80/90 and Oil Stabilizer that everyone talks about. I've also dropped my shift points way down so I'm into 2nd at about 5mph and into 3rd at about 10mph; it's much more cooperative! I do still get the occasional engine burp while underway, but it's only when hot and it seems to go away when I increase the advance to maximum. I can also report that the hot idle now seems stable and smooth. For someone who's accustomed to listening to modern engines, it's amazing how much more of the mechanical sounds you can clearly hear in an old-fashioned, long stroke engine when it's running at 360 rpm. I'm definitely making progress. Thanks for all the help. I'm sure I'll have more to report in the coming days.

Quick Update: I reduced the idle from 700 to 360 and retarded the timing a bit more. Now for the first time, the spark lever produces a noticeable RPM difference from top to bottom. Using a timing light, I can see that I'm at 22° / 460 rpm at full advance and 0° / 360 rpm at full retard. My vacuum has dropped three pounds to 16 lbs; undoubtedly the result of dropping the idle from the previous 700 rpm. The new lower idle definitely helps get into gear while stopped, but it still protests every so often when hot, so I'll probably try the 2:1 mix of Lucas 80/90 and Oil Stabilizer that everyone talks about. I've also dropped my shift points way down so I'm into 2nd at about 5mph and into 3rd at about 10mph; it's much more cooperative! I do still get the occasional engine burp while underway, but it's only when hot and it seems to go away when I increase the advance to maximum. I can also report that the hot idle now seems stable and smooth. For someone who's accustomed to listening to modern engines, it's amazing how much more of the mechanical sounds you can clearly hear in an old-fashioned, long stroke engine when it's running at 360 rpm. I'm definitely making progress. Thanks for all the help. I'm sure I'll have more to report in the coming days.

Thanks Hugh, You’ve given me an idea. I have no idea what RPMs I’m running at idle but I’d guess I’m at least 800. Sounds like I need to drop the idle and see what happens.

Yes! It’s much worse when hot. I’m running Amsoil SAE 250 though. What’s heavier??? I could try asphalt I suppose LOL.

I'm fully aware that downshifting in a car this old is almost never going to work, but every so often I have an issue I wasn't expecting. On occasion, I have to shut the engine down to get it into first gear (or reverse). This doesn't happen all that often, but sometimes when I'm sitting at a stop sign with the clutch fully pressed to the floor, the transmission gears won't stop turning. Any attempt to get into gear is immediately met with the typical threat of grinding, so I try to wait it out. A few times I've waited well over a minute, but they just won't slow down. The only solution seems to be shut the engine down, slip it into first gear, restart the engine and go on as usual. Seems strange. Is this normal? Any suggestions if not?

Today I tried a few more things and the engine is running much better! The thing that made the most difference was adjusting the timing (again). A few days ago I had set it by-the-book, by watching the valves, finding the "17" mark on the flywheel, gently moving the distributor CCW until the opening-point was reached, etc.... By the book it was correct. But I remembered that my 1954 Lincoln doesn't run well when the timing is set to the original specifications, so maybe the Buick has a similar issue. Anyway, with the engine running, I just loosened the distributor and moved it ever so slowly back and forth to see where the engine ran best. The sweet spot ended up being about 1/4 inch clockwise from where it had been (measured at the outer circumference of the distributor base just beneath where the cap meets the base). I think that means I retarded it, but I'm really not 100% positive, nor do I have any idea if that's a large adjustment or a small one. I then re-adjusted the fuel and air knobs on the carburetor for best idle. Interestingly, even after achieving a smooth idle, I had to increase the fuel knob several times to get the car not to feel herkie-jerkie and starving under acceleration. I had to do similar with the air knob, but I think I've made some good progress to a better end at this point. The results: vacuum is up to 19 lbs (was 16 lbs) the herkie-jerky surge-cut-surge-cut-surge-cut behavior is gone the fuel knob is backed out 2.1 turns from fully seated the air knob is backed out 1.5 turns from "flush" with the marker the skipping while driving is drastically less, not entirely gone, but I can usually eliminate it by playing with the spark lever on the steering wheel (it seems to prefer more advance as it heats up) the car idles much better now, just a tiny bit of hunting, but I'm being a bit picky there, it's dramatically better now, I may get a video tomorrow for posting the engine is noticeably less loud during acceleration, I have no idea why this would be, but it used to make more of an exhaust growl under heavy throttle FUNNY - At one point during all my test driving today, after some very encouraging success, I thought all was for not.... the car suddenly lost all power and would barely maintain speed. When I opened the hood, I discovered that this little lever had fallen off. The PO had wrapped a paperclip around the bracket (clearly visible in this picture) to hold it onto the pivot point instead of simply sliding a cotter pin through the hole. Hmmmm... I quickly put it back on, this time with a proper cotter pin and the good behavior returned immediately. Can anyone tell me what this is? And maybe what it does? I'm going to guess it's the accelerator pump but I have no idea what the effect would be of having it fall off like this. .

HI Ed, Thanks for offering, I may well take you up on it. That's a really great coil testing tool you've got too. I'm pretty sure the coil in my car is healthy because it throws a bright bluish-white spark and it'll easily jump at least 3/4 of an inch.

Hi Mario, Thanks for the details. If there's a reputable rebuild service, I'd definitely consider sending my carburetor to them and let a professional deal with it. This car had a total restoration back in 1996 and hasn't seen an actual road since (until I bought it that is); just on and off trailers to shows. My intention is to drive it to local shows, but all the time sitting with nothing more than 100 yard drives took it's toll. It's definitely in need of some fine tuning. That carburetor appears to be a 10-103.

Thanks Larry, A little more reading and I found a few write ups indicating that the pin-hole problem causes loss of vacuum. From what I've read, 18-19 lbs of vacuum is ideal and I'm pulling around 16 lbs with a regular blip down to 15.5. So it's not ideal, but I suppose it's not all that bad either. When I put in the new points, things seemed to get a bit worse. They're gapped properly at 0.018, but I wonder if I effected timing when I installed them. The car now idles quite a bit faster than before and it now prefers the advance lever at full advance. Before it didn't really make much difference where that lever was. I think I'll be adding a timing check to my to-do list along with the vacuum tank rebuild.

You may be onto something. Now that it's got new points, I've replaced everything in the ignition system that I can think of.... coil, points, condenser, rotor, cap, wires and plugs and it's not really any better. Interestingly, I pulled a plug wire to see what color the spark would be and it's perfect; bright bluish-white and it jumped almost an inch. (it packs a good whack too!) Seems to me the spark is good. On my test drive a few minutes ago, it was sputtering, then refused to go above 10mph. I pulled over a number of times to play with the fuel and air knobs and was able to see big changes, both bad and good..... after a few attempts was able to get the engine running well enough to get home. Here's another interesting clue: The engine idles alright, but when I'm driving, it really jerks back and forth as if I'm hitting and releasing the throttle rapidly...... but, if I just hold the throttle button to the floor, it runs smoothly without all the back and forth jerking. So I'm thinking maybe the carburetor could be worth looking into??? I'm also wondering if the fact that the engine runs smoother with the "pedal on the floor" is an indication that the intake tube has pin holes. Maybe the wide open throttle helps overcome an exhaust gas leak, where part-throttle can't? Then again, it could just be rotational inertia smoothing out the skipping underneath. Can anyone describe the symptoms of the pin hole problem? I haven't been able to find a description of what to look for.... just that it causes problems. No idea what problems though. I just bought the Marvell book from Bob's, along with their vacuum fuel tank repair kit. I just wish I had some experience to draw on with this process or even better, a good mechanic to bring the car to.... I'm not the guy I'd hire to troubleshoot this stuff. LOL

Good to know. You caught me before I tried it. The new points and condenser are in and there wasn't much change.

Thanks. I've verified good ground to the distributor.

Ah, it's a good move. My brother just moved to FL too. Any recommendations for a pre-war mechanic up this way? I'm going to need someone to rely on, because I like this car; it's going to be with me for a long time. As a last test for the night, I removed a condenser that was attached to the positive lead on the coil. Not sure why it was there, I've never seen one in such a place before, but I removed it to see if it had any effect. During another 6 mile test drive, it did seem to run a bit better. The skipping feeling was still there, but it seemed to be considerably less. The hot idle was just as bad as before though. Maybe I just had a lucky run?? Or maybe we're on to something?? Next, I'll see if removing the condenser in the distributor has any effect. And then, when my new condenser and points arrive Tuesday, I'll see if those have any effect. Thanks as always! I'm looking forward to laughing about this when it's all figured out.