What went wrong?, it was running great and then not at all |
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What went wrong?, it was running great and then not at all |
Type 47 |
Mar 15 2023, 03:59 PM
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#1
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Senior Member Group: Members Posts: 784 Joined: 1-June 10 From: St. Louis, MO Member No.: 11,790 Region Association: None |
so we put the original 62k engine back in that had not had the distributor removed. Adjusted the valves (again after we put about 10 miles on it) we rebuilt the Webbers and it fired up. We did some timing and tweaking on the carbs.
It ran OK but a little shy of perfect. I replaced the wires and it seemed to improve it but idled a little high around 1,200. My son came over to work on it the next day, but I wasn't home. All of a sudden, it won't even run. we swapped distributers (both 009's) with the parts car, then swapped points (adjusted to 0.016). no improvement. tested spark to all four cylinders. I seems like it's really out of timing but we didn't change it much. (except for the fact that we took the distributor out) my son says we have spark, too much fuel, and not enough air. What do we do next????? |
nditiz1 |
Mar 21 2023, 06:37 PM
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#2
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Senior Member Group: Members Posts: 1,202 Joined: 26-May 15 From: Mount Airy, Maryland Member No.: 18,763 Region Association: MidAtlantic Region |
There are definitely different levels of cleaning. Even to go as far as dipping them in Chem dip. The rebuild kit will break the carb down enough to get most areas clean. You need to pay attention to the passages and shoot brake cleaner and compressed air through them.
Did you perform the float adjustment procedure. Very key to setting carbs up? Ensure you have proper fuel pressure to the carbs (3psi) Dialing in carbs is not difficult, but it can be time consuming. You also need to make sure the the engine is warm. Since it will at least idle you already have a base. Pop off the linkage on side so it does not interfere with getting them to idle smoothly. Use the snail gauge to ensure the vac on both L and R are the same. Also ensure the the throats on the same carb are also in sync. The bypass screws should start all the way closed. These screws will be opened to increase the vac on that throat. In the perfect world all throats will be the same as the pull on each cylinder is perfectly matched, but I have yet to encounter this so minor adjustment is always needed. Now that all 4 carbs are in sync you can use the Idle speed screw to bring the idle to around 1000. When you do this your sync will be off so readjust L and R. Now you should be running ~1000 and the Land R are in sync. Start turning the mixture screws out from all the way in about 3 turns. Slowly screw it in until the engine starts to stumble. If the idle never drops you could have an issue (dirt) with that throat. The point at which the engine starts to stumble means it is going lean. I usually back the screw out a half turn or quarter depending on the jet size. This will get you close to best lean idle. If the engine is worn the same all 4 mixture screws should be within a quarter to half turn of each other. It is a good practice to perform this step a few times as it could increase you idle. This will make you move the speed screws out to lower idle which will change the mixture. It is a cycle to get everything into a harmonious balance. If you have made it this far the engine should be pretty smooth. If not you could have any number of issues, dirty carbs, intake leak, exhaust leak. The last step is to sync the carbs under throttle from linkage. You use the sync gauge again holding different RPM to ensure the L and R are the same. If one side is pulling more then adjust the linkage. You never need to touch mixture, idle speed, or bypass screws. The last step involves driving, getting a feel, and using a AFR meter to possibly rejet. |
Type 47 |
Mar 21 2023, 08:13 PM
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#3
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Senior Member Group: Members Posts: 784 Joined: 1-June 10 From: St. Louis, MO Member No.: 11,790 Region Association: None |
There are definitely different levels of cleaning. Even to go as far as dipping them in Chem dip. The rebuild kit will break the carb down enough to get most areas clean. You need to pay attention to the passages and shoot brake cleaner and compressed air through them. not chem dipped but carb cleaner and air (son thinks BC is to caustic) Did you perform the float adjustment procedure. Very key to setting carbs up? probably not, son's tech school taught nothing about carbs, we probably assumed carbs taken off properly running car was good for a baseline Ensure you have proper fuel pressure to the carbs (3psi) That's where the FPR is set will follow your tuning advise. I'm hoping this experience is teaching someone some patience and understanding. BTW, didn't work on the car today. Want to soak all this info in and move forward tomorrow. |
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