1.7 with Weber 34s - timing & running issues, Hard starts, sputters, backfires.... |
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1.7 with Weber 34s - timing & running issues, Hard starts, sputters, backfires.... |
Boomingbeetle |
Nov 1 2016, 09:58 PM
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#1
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Member Group: Members Posts: 118 Joined: 1-November 16 From: Orange County Member No.: 20,556 Region Association: Southern California |
I recently got back into the 914 world with the purchase of a nice '71 with sideshift trans and a 1.7L, now I need some help and suggestions.... SO I have officially become a registered user instead of just lurking and searching.
My motor runs for the most part, but it had a hell of a time starting up after a week, and it does spit and sputter a bit. After getting it to my workshop I adjusted the valves, I replaced the cap and rotor which were badly corroded. Plugs are in great shape, gaps are good, but when I went to set timing I noticed the distributor pinion was 180-deg off and the #1 plug wire was actually pointed toward the #1 cylinder. I moved the pinion to the correct "12-degrees" at TDC and corrently arranged the wires. I could not get it to fire up. I had to leave until this weekend but when I went back I checked a few more items. The distributor is a 009 with electronic ignition, not sure what brand. Coil shows 4-Ohms and I have good 12V to the coil. It started- but I had to baby it and hold the throttle until it was warmed up. Now I was finally able to check timing, but I cannot get it to rev to 3500 rpms. I can get to about 25-28 deg BTDC between 2500 and 3000, but it seems to fall flat and pop/sputter above 3000 and advancing the timing any further doesn't seem to make a difference. Weird because I was generally driving the car between 2500-4500 rpms before parking it to do this work. At first I thought there was a voltage drop at the ignition, now I'm beginning to think my carbs are not jetted correctly, but why could I drive it 70-80mph in midrange RPMs? Any ideas? I'll be heading back to the shop Friday to do some more troubleshooting but any feedback is appreciated. I can take pics if any further info is needed... Thanks! |
Boomingbeetle |
Nov 4 2016, 12:53 PM
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#2
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Member Group: Members Posts: 118 Joined: 1-November 16 From: Orange County Member No.: 20,556 Region Association: Southern California |
This week I was able to start, no problem! I still had to blip the throttle and keep pressing the peddle for a minute or 2. After letting the engine warm up I was even able to set the timing above 3000 RPMs. Know what I did? I replaced the crappy "Duralast" ignition rotor with an Echlin unit from NAPA (no one had Bosch in stock)!
The car runs much better, BUT I get a lot of popping through the carbs above 3000rpm, regardless of total timing advance, I played with it between 20-33 BTDC and still pops. Looks like the carbs are straight out of the box - .52 idle jets, .160 air, .130 mains. Suggestions? |
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