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UberElectricEagle |
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#1
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atomic ![]() Group: Members Posts: 43 Joined: 10-August 09 Member No.: 10,659 Region Association: None ![]() |
Greetings. I am new to the Porsche world and I purchased a 1972 914 1.7 about a month ago. It's a pretty nice car over all, but I think the motor, or part of the motor, might be toast.
When I purchased it, it badly needed a muffler. The knocking noise was harder to notice and sounded more like an exhaust leak over the horrible sound of the lack of a working muffler. The car seemed to run decent even with the poor exhaust and the price was good so I bought it. I just wanted a decent car over all that I could drive around for fun on sunny days before the winter gets here. It came with stainless heat exchangers I installed and I installed a really nice dual muffler from Dave at Triad. When I fired it up with the new muffler, I really noticed the knocking when I drove it since the all the exhaust leaks were now sealed up and I wasn't wearing ear plugs. At idle it's not too bad, but once I get going, the knocking is very noticeable. It's odd too, because it's not real consistent under power in motion. To me it sounds like the noise is coming from the #1 cylinder. I think the cylinder is providing no power, because when I take the wire off the cap, there is really no change in performance. (I put a video link of the horrible sound below.) Any advice on where to go from here would be great. My gut feeling is telling me the motor is going to have to come out. If I'm going to do all that, I might as well put a 2.0 liter in or ????? I'd even settle for just a solid running motor with some minor upgrades to make it a little quicker. Any advice on what route to take on a good used motor would be great. I guess A motor that runs on 4 cylinders would be an upgrade. Thanks for your help, a mildly depressed Sam http://www.youtube.com/watch?v=a5JhEd7SUH4...re=channel_page ![]() |
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Rod |
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#2
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Senior Member ![]() ![]() ![]() Group: Members Posts: 616 Joined: 1-January 08 From: Farnham UK Member No.: 8,526 Region Association: England ![]() |
Yes but it would be making a very different noise. This now has me stumped, you have compression, fuel and spark.. I have a feeling that fuel isn't getting through though..
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UberElectricEagle |
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#3
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atomic ![]() Group: Members Posts: 43 Joined: 10-August 09 Member No.: 10,659 Region Association: None ![]() |
Yes but it would be making a very different noise. This now has me stumped, you have compression, fuel and spark.. I have a feeling that fuel isn't getting through though.. This is my feeling, just a feeling because I am far from knowing the ins and outs of cars. I know just enough to screw myself over. I think there is so much oil in the combustion chamber that it's not able to do a proper fuel and air mixture and it will not fire properly. #1 is the only plug that has come out black. And it was black right after I put a new one in and ran it for 5 minutes. And not a burnt black , but just a soaked in oil looking black. If that makes sense. I would think too that spraying the carb cleaner down in there is also loosening up some of the old crud in that #1 and making a black half oil have carb cleaner like substance. It has to be really ugly looking in #1 if it hasn't been firing properly for some time. |
Rod |
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#4
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Senior Member ![]() ![]() ![]() Group: Members Posts: 616 Joined: 1-January 08 From: Farnham UK Member No.: 8,526 Region Association: England ![]() |
Yes but it would be making a very different noise. This now has me stumped, you have compression, fuel and spark.. I have a feeling that fuel isn't getting through though.. This is my feeling, just a feeling because I am far from knowing the ins and outs of cars. I know just enough to screw myself over. I think there is so much oil in the combustion chamber that it's not able to do a proper fuel and air mixture and it will not fire properly. #1 is the only plug that has come out black. And it was black right after I put a new one in and ran it for 5 minutes. And not a burnt black , but just a soaked in oil looking black. If that makes sense. I would think too that spraying the carb cleaner down in there is also loosening up some of the old crud in that #1 and making a black half oil have carb cleaner like substance. It has to be really ugly looking in #1 if it hasn't been firing properly for some time. Exactly my thoughts too.. The reason that piston may be making compression is that it is sooo full of crud that it's reducing the swirl area. It needs to be cleaned out - which running at tickover is not going to do, it needs to be revved under load to clean te sucker out, but is it getting fuel in the first place. With regards to the adjustment on your specific carb - sorry, but I have 0 idea. (IMG:style_emoticons/default/sad.gif) |
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