Runs rough - spark plug doctors? |
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Runs rough - spark plug doctors? |
torakki |
Apr 17 2021, 07:31 PM
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#1
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Newbie Group: Members Posts: 43 Joined: 5-October 18 From: Nor Cal Member No.: 22,545 Region Association: Northern California |
On my '74 2.0, I can't get it to run right. It's gone through a restoration and put aside for 2 years. Now, back on it and it's almost done but[b] number 1 and 4 spark plugs are clean/wet and 2 and 3 are black, (after 10 seconds of running). What I've done so far: Rebuilt MPS, gapped points, static timing, set fuel pressure at around 27 lbs. Compession between 90 and 110. Plugs are sparking. All injectors spray (not sure of pattern). I believe plugs were new 2 years ago. They look new. It runs really rough, white smoke out exhaust and some mild popping. I though, maybe injector triggers but all are working from my, spray in the cup, test. Dizzy backwards? Any ideas to what's going on??
Thanks for any suggestions. |
Tom_T |
Apr 18 2021, 11:55 AM
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#2
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TMI.... Group: Members Posts: 8,318 Joined: 19-March 09 From: Orange, CA Member No.: 10,181 Region Association: Southern California |
On my '74 2.0, I can't get it to run right. It's gone through a restoration and put aside for 2 years. Now, back on it and it's almost done but[b] number 1 and 4 spark plugs are clean/wet and 2 and 3 are black, (after 10 seconds of running). What I've done so far: Rebuilt MPS, gapped points, static timing, set fuel pressure at around 27 lbs. Compession between 90 and 110. Plugs are sparking. All injectors spray (not sure of pattern). I believe plugs were new 2 years ago. They look new. It runs really rough, white smoke out exhaust and some mild popping. I though, maybe injector triggers but all are working from my, spray in the cup, test. Dizzy backwards? Any ideas to what's going on?? Thanks for any suggestions. There are all sorts of plug condition charts out there if you google for it, & this one is from Champion: https://www.austincc.edu/wkibbe/plugchart.pdf The 2 marked 2 & 3 look to be carbon fouled if dry or oil fouled if wet - & you said 1 & 4 were "wet" - is that H2O moisture or fuel? White smoke is either moisture (H2O) if it dissipates in the air, or oil if not. 90 - 110 lbs seems low at the 90s one(s) - but correlate those to which plug. It could just be that the engine wasn't warm enough yet to get the rings to seat properly, & therefore also allowing some oil blow-by to cause the white smoke. Popping sounds like a misfire. Sitting for 2 years then run for 10 seconds - it's not going to get to operating temperatures, won't have time to burn off whatever collected in there, etc. First - what's your fuel condition? Is it Unleaded left to sit for 2 years? Did you add stabilizer before storing it? Does it have water separation in the tank & now in the lines & injectors, etc. after running? You may have to drain & clean the tank & refill with fresh fuel, maybe lines too. Then maybe clean off the plugs, get them back into the original cylinders, then let 'er run a bit longer for several minutes. Then assess by each on plug condition, exhaust & running - but correlate to the proper position & cyl. # & compression readings - as JamesM noted above. If you get stuck on this & are close to the Bay Area part of NoCal, then there's HPH in Redwood City & a couple of other shops who know our 914s to get it running properly again. Good Luck! (IMG:style_emoticons/default/beerchug.gif) Tom /////// |
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