The dreaded knock. |
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The dreaded knock. |
atmadsen914 |
Dec 28 2008, 11:06 PM
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#1
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Am I sure I like old cars? Group: Members Posts: 45 Joined: 7-September 07 From: Carlinville IL Member No.: 8,087 Region Association: Upper MidWest |
I recently rebuilt a 2.0/4 motor and installed it in my 914. After getting many fuel system issues sorted out I finally was able to drive it a few times but after about 150 miles of driving. It developed a knock. I readjusted the valves and the knock seems to get better but never goes away. The knock is audible from idle to about 1500 rpm then smoothes out. When I roll the motor over by hand I can hear a knock on every cylinder.
The motor is basically stock with the exception of a web cam (73 grind). I am about to pull the motor and start disassembling as the sound does not seem good. However after many hours of tinkering has not gotten worse. Ideas? or do I just get to do it all over again? |
2-OH! |
Dec 30 2008, 10:35 PM
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#2
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Senior Member Group: Members Posts: 552 Joined: 17-October 03 From: Santa Clarita, Kalifornication Member No.: 1,253 |
OK, pull it if you want, but I had the same exact noise and problem...
Here's what I did to correct it: 1. Make certain the distributor is in correctly (which ever one you use)...Haynes manual...Mine wasn't 2. Make certain your spark plug wires are in the correct firing order..Mine weren't... These two things will produce the noise you have... 3. A 1.7 distributor will run it, but with the Webcam 73, it will ping and Octane knock under acceleration...2.0 works wonderful... 4. I am still experimenting with the timing but I estimate it will be perfect around 13 to 15 degrees @ 3500 RPM, red line (27 degrees BTDC), engine warm... 5. Webcam will make it hard to idle...I ended up with a small orfice to create a planned vacuum leak...She idles like a rock @ 1100 and has wonderful torque right up to red line...Love that cam... Good Luck !!! 2-OH! |
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