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Adriel Rowley
Samba Member
Joined: October 12, 2006
Posts: 4876
Location: Mesa, Arizona
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 Posted: Fri Jun 17, 2011 6:03 pm Post subject: Cylinder Performance |
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Now that the Squareback can be driven (have turn signals but still odd wiring and no headlights or idiot lights. F.Y.I.) wanted to figure out why number three cylinder is not firing or poorly. To start off the day of diagnosing, there was debris between the head casting and the spark plug, so as I could not get the socket on the spark plug, so off came the runners. I tried a magnet, would not pick up but went to number four, and then ended up wedged in between the fins, so left it. Pulled number three and was fouled: black as coal. Wire wheeled it, and reinstalled. Checked four, and was clean as it was when I put it in less than 25 miles ago (unknown hours though). Therefor, figured number three must be getting too much fuel, and checked number three injector beside four. Got a bit of a stream rather than number four's fog. So, swapped to another injector but did not test, ASSuming it was fine. However, with engine running, still is not quite right. Pulled the number three spark plug wire from the distributor cap, I get about half the response as I do from the others. I do notice the spark is brighter than before, but hard to be sure in bright light. I am now thinking after all the sitting with gasoline the injector did in its life, might need cleaning. So sending out a set to be tested and cleaned, since I have heard this strong recommendation many times but thought all was fine. Lesson learned: prevent rather than fix.
My question is how much of an affect does variations in spray (already know what streaming does) have on cylinder performance, i.e. variations of fine atomization. Also, what about spark plug gap? I am using the disk gapper, so thinking I could be in the range of 28 to 30 thousandths, and do not know if this is something to be aware of.
_________________
Please consider I am Autistic, so I process information differently and still working on social skills. Thanks.
Dad's 1964 Beetle purchased September 1968.
https://www.thesamba.com/vw/forum/viewtopic.php?p=9252810#9252810
1971 Sunroof Squareback with Fuel Injection
http://www.thesamba.com/vw/forum/viewtopic.php?t=219811&highlight=squareback+rejuvenation |
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Bobnotch
Samba Member
Joined: July 06, 2003
Posts: 23552
Location: Kimball, Mi
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| Posted: Sat Jun 18, 2011 6:16 am Post subject: Re: Cylinder Performance |
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| Adriel Rowley wrote: |
| Now that the Squareback can be driven (have turn signals but still odd wiring and no headlights or idiot lights. F.Y.I.) wanted to figure out why number three cylinder is not firing or poorly.... Also, what about spark plug gap? I am using the disk gapper, so thinking I could be in the range of 28 to 30 thousandths, and do not know if this is something to be aware of. |
Yes, too large a plug gap can cause misfiring, hard starting, spark jump, and possible damage to other components. Try to get it back down to around .024 inch.
_________________
Bob 65 Notch S with Sunroof
71 Notch ...aka Krunchy; build pics here;
http://www.thesamba.com/vw/forum/viewtopic.php?t=249390 -been busy working
64 T-34 Ghia...aka Wolfie, under construction... http://www.thesamba.com/vw/forum/viewtopic.php?t=412120
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| Tram wrote: |
| People keep confusing "restored" and "restroyed". |
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Adriel Rowley
Samba Member
Joined: October 12, 2006
Posts: 4876
Location: Mesa, Arizona
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| Posted: Sat Jun 18, 2011 11:11 am Post subject: Re: Cylinder Performance |
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| Bobnotch wrote: |
| Adriel Rowley wrote: |
| Now that the Squareback can be driven (have turn signals but still odd wiring and no headlights or idiot lights. F.Y.I.) wanted to figure out why number three cylinder is not firing or poorly.... Also, what about spark plug gap? I am using the disk gapper, so thinking I could be in the range of 28 to 30 thousandths, and do not know if this is something to be aware of. |
Yes, too large a plug gap can cause misfiring, hard starting, spark jump, and possible damage to other components. Try to get it back down to around .024 inch. |
Bob, thank you for the help!  For some reason, I thought the gap was 0.028... Will close it down. What kind of damage could it do?
_________________
Please consider I am Autistic, so I process information differently and still working on social skills. Thanks.
Dad's 1964 Beetle purchased September 1968.
https://www.thesamba.com/vw/forum/viewtopic.php?p=9252810#9252810
1971 Sunroof Squareback with Fuel Injection
http://www.thesamba.com/vw/forum/viewtopic.php?t=219811&highlight=squareback+rejuvenation |
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Adriel Rowley
Samba Member
Joined: October 12, 2006
Posts: 4876
Location: Mesa, Arizona
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| Posted: Tue Jun 21, 2011 3:54 pm Post subject: |
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Finally made it out to the Squareback; work has been unpredictable. Installed the rebuilt spark plug wires and installed nicer than the new ones. They fit better in the holders and are tighter on the cap. Only concern was number one was a stretch. They should be loose right?
Started it up, and seemed a tad better, but number three was still week. Disappointed, so decided to take a drive up part of the coast as was not in the mood to deal with it.  Got onto the road, and was way better. Just as I got onto one of the larger roads leading out to the main drag, my right foot hit the floor. God was watching as was able to coast into the alley behind Jack's house. Turned out the throttle cable slipped out of the barrel nut, so fixed that, and went on around. This time, it started to fall flat on its face when I left the limit line. Went back around, thinking it felt like it was lugging. Then had the idea of trying to go back into first... it was in second gear!  Today been having blank moments; guess the stop sign came up too soon. Plus, third time I have driven it with the bushing replaced. Finnished going round and headed out. Felt good to not care and get out and enjoy it, especially on a good day for a sunroof. Only thing was it was hard to get it up to 50 M.P.H. as it run out of power to do it. When coming back was able to persuade it up to 53 M.P.H. but took feathering the throttle. This reminded my I had not checked the T.V.S.. When I got back, I tested it, which was a bit of a challenge with the warm engine. Idle circuit shows 0 Ohms along with the fourth test, and the second and third tests get odd results (Adney test). Seems that might be my problem?
Anyone have an extra four pin T.V.S.? Been using a five, but switched to this four pin thinking it worked; now need to remember where I put it.
_________________
Please consider I am Autistic, so I process information differently and still working on social skills. Thanks.
Dad's 1964 Beetle purchased September 1968.
https://www.thesamba.com/vw/forum/viewtopic.php?p=9252810#9252810
1971 Sunroof Squareback with Fuel Injection
http://www.thesamba.com/vw/forum/viewtopic.php?t=219811&highlight=squareback+rejuvenation |
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