ArdWrknTrk Posted October 7, 2019 Share Posted October 7, 2019 Plugs look fine but the second looks a touch oily around the neck. Thank goodness we in the U.S. don't have MTBE any more. Plugs all looked bright orange (like flash rust) back then. Point an IR thermometer at each exhaust port and see if one is cooler that the rest if you're looking for a miss. Are you sure it isn't an exhaust noise you're hearing, Cory? Not exhaust noise, no...it's definitely a vibration, I just can't tell if it's normal or not. Pretty sure it isn't... Good idea on the exhaust port temp check. I may try that tonight before I do a compression test. So how does that oil get up around the plug anyway? I guess it works it's way up past the threads? The engine uses no oil and doesn't smoke or anything. It IS brand new, so it shouldn't...but anything is possible. I have no idea how it gets there. It's not like my ex's old Isuzu with plugs in the valve covers. Just an observation.... I hope that's not oil pushing up out of the cylinder! Maybe there was oil in your socket? Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 7, 2019 Author Share Posted October 7, 2019 The plugs look fine, although the mix might be a touch lean. Do you have EGR? If so, do you know if it is coming in? If not, has your dizzy been tuned to account for the lack of it? Cory - Don't miss my question about EGR. If your vibration is at part throttle you may have too much advance, which could be caused by having an EGR dizzy but no EGR. Link to comment Share on other sites More sharing options...
1986F150Six Posted October 7, 2019 Share Posted October 7, 2019 Cory - Don't miss my question about EGR. If your vibration is at part throttle you may have too much advance, which could be caused by having an EGR dizzy but no EGR. Cory, does the vibration exist at idle speed? If so, remove the v-belts and then see if the vibration goes away. If it does, check H2O pump, alternator, P/S pump, fan, etc. Link to comment Share on other sites More sharing options...
1986F150Six Posted October 7, 2019 Share Posted October 7, 2019 Cory, does the vibration exist at idle speed? If so, remove the v-belts and then see if the vibration goes away. If it does, check H2O pump, alternator, P/S pump, fan, etc. I drove my truck to work, this morning, and watched as the odometer revealed 213K miles. Go Ford! Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted October 7, 2019 Share Posted October 7, 2019 I drove my truck to work, this morning, and watched as the odometer revealed 213K miles. Go Ford! KEEP going Ford! Link to comment Share on other sites More sharing options...
grumpin Posted October 7, 2019 Share Posted October 7, 2019 I drove my truck to work, this morning, and watched as the odometer revealed 213K miles. Go Ford! My F250 has the least miles! Edit: I agree with Gary, those plugs look too good to me. Lean. Link to comment Share on other sites More sharing options...
Rembrant Posted October 7, 2019 Share Posted October 7, 2019 Edit: I agree with Gary, those plugs look too good to me. Lean. Ok, good to know. To correct this I'd want to change the main jets, yes? I'm running a new Holley 4160 600CFM 4bbl carb. When it was dyno tuned, the stock #66 jets were removed and #68 jets were installed. The dyno testing however was done with open long tube headers and mostly with an open carb. Also, the dyno tests were all 2800 RPM to redline. Maybe it's still running too lean down in the lower RPM's where I drive it. Link to comment Share on other sites More sharing options...
Rembrant Posted October 7, 2019 Share Posted October 7, 2019 Cory - Don't miss my question about EGR. If your vibration is at part throttle you may have too much advance, which could be caused by having an EGR dizzy but no EGR. Gary, sorry I did miss that. No EGR system at all. I am running my original distributor, but with modified advance. If I remember correctly, I have my base timing set at 12 degrees, and mechanical is 20 degrees. Vacuum advance if it's working correctly would be another 10 or 20 degrees above that? Great questions Gary. You're giving me more to think about here. Maybe a lean misfire? I will check over the timing again and see where it all is. Cory, does the vibration exist at idle speed? If so, remove the v-belts and then see if the vibration goes away. If it does, check H2O pump, alternator, P/S pump, fan, etc. More good questions. Since I have a bit of a lumpy cam in there, it has a bit of a lopey idle anyway, so it's hard to tell. Pulling the belts is easy to do though, I will give that a try also. Thanks Guys. Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 7, 2019 Author Share Posted October 7, 2019 Cory - Don't miss my question about EGR. If your vibration is at part throttle you may have too much advance, which could be caused by having an EGR dizzy but no EGR. Gary, sorry I did miss that. No EGR system at all. I am running my original distributor, but with modified advance. If I remember correctly, I have my base timing set at 12 degrees, and mechanical is 20 degrees. Vacuum advance if it's working correctly would be another 10 or 20 degrees above that? Great questions Gary. You're giving me more to think about here. Maybe a lean misfire? I will check over the timing again and see where it all is. Cory, does the vibration exist at idle speed? If so, remove the v-belts and then see if the vibration goes away. If it does, check H2O pump, alternator, P/S pump, fan, etc. More good questions. Since I have a bit of a lumpy cam in there, it has a bit of a lopey idle anyway, so it's hard to tell. Pulling the belts is easy to do though, I will give that a try also. Thanks Guys. The dyno testing was probably all done at WOT and with essentially no vacuum to the dizzy. So while the mix is probably right at WOT, it might be lean at cruise. And, while the dizzy has a modified advance, I doubt that they corrected the vacuum advance, which is where the extra timing comes from during EGR. And too much advance can cause roughness - especially with a lean mix. The test is simple - pull and plug the vacuum line to the dizzy. If the vibration goes away you've found at least part of the problem. Link to comment Share on other sites More sharing options...
Rembrant Posted October 7, 2019 Share Posted October 7, 2019 The dyno testing was probably all done at WOT and with essentially no vacuum to the dizzy. So while the mix is probably right at WOT, it might be lean at cruise. And, while the dizzy has a modified advance, I doubt that they corrected the vacuum advance, which is where the extra timing comes from during EGR. And too much advance can cause roughness - especially with a lean mix. The test is simple - pull and plug the vacuum line to the dizzy. If the vibration goes away you've found at least part of the problem. Gary, Yes, yes, and yes! The dyno pulls started at 2800 RPM and went to 5500 RPM if I recall correctly, so any fuel corrections made were in reference to those RPM's under load. I have the Crane adjustable vacuum advance kit installed, and I have it set for maximum advance (weakest springs). Truth be told, I meant to go back and play with this some more to check and/or adjust it if necessary. I did play with it initially after installing the engine, but never did go back to fine tune it. I will check on this for sure. One potential issue I had with the centrifugal advance was finding out exactly when it was advancing. I was having a tough time checking this stuff since I couldn't rev the engine and check the timing at the same time...or not very well at least. The centrifugal timing was supposed to be all in by 2800 RPM (I think), but it did not seem like it increased gradually like it was supposed to. It seemed like all of the advance was above maybe 2200 RPM. Again...going by fuzzy memory here, but it is all good because now I have a very good excuse to check all of this stuff over to get it dialed in. Link to comment Share on other sites More sharing options...
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