67Rolla-Ken Posted March 23, 2014 Report Share Posted March 23, 2014 :( It never ends! Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 26, 2014 Author Report Share Posted March 26, 2014 (edited) Not sure quite how to word this update, so I'm just going to wing it. The hope that nothing is terminally wrong is getting stronger. Topped up the oil on Monday night & drove BT to work on Tuesday. Started first crank (on a cool morning too), idled fine, drove as per usual. Had a chat with several people wise to the ways of 4A-G's, including an hour-plus long phone call to kickn5k (Stu, love you long time man!) & it was on my way to borrow an inspection camera that I began to notice a few things about when & how the oil smoke was appearing. So here's my thoughts: Air:fuel mixtures are seriously rich at part-throttle (you know, sitting on 60km/h, 100km/h etc, that much throttle), which is where I do spend the majority of my time driving at, 13.0:1 (air:fuel) at best, 11.8:1 at worst. When coasting down a hill with no throttle applied, I saw 10.5:1 at worst. It is when I apply throttle after the engine has been running for a short period of time at these ratios that the smoke appears in volume. Rich mixtures will wash oil off the bores/burn it off, as well as dilute the oil, reducing the viscosity, As I was running a 10w-40 oil, it didn't take much for the oil to be able to seep past the rings into the combustion chamber & be burnt off. The used oil reeks of petrol. Going to do my best to lean the part-throttle mixture out & while I haven't yet had a look inside the bores to check for any glazing of the bores, it is next on the list of things to do. I have also changed to a Penrite HPR 50 oil, slightly thicker, the smoke clouds still appear as per the above circumstances, but less of it. I'm also taking the opportunity to 'load up' the rings as much as possible, so lots of throttle but keeping under 3,500rpm. Have been finding a few hills on my travels & putting them to good use. This is because I was enlightened that the chrome piston rings I'm using (instead of cast rings) take a wee bit more/are a little more finicky to bed in. BTs only done ~1,700kms at this point, so it's possible that they haven't yet bedded in properly yet, the fuel soaked oil/rich mixtures most likely wouldn't have helped them either. For the spark-plug-reading gurus, a photo of the spark plugs that are ~1,000kms old, cylinders 1 - 4 from left to right. 3 & 4 look okay (relatively), it's 1 & 2 that have me a little concerned. Enough of my rambling though, I've had bugger all sleep the last few days so I'm going to go pass out. The inspection camera will tell me more tomorrow. P.S - Finally got the T3 injector port plugs in the mail & installed them, very happy with the quality of the product. Edited March 26, 2014 by carbonboy Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 29, 2014 Author Report Share Posted March 29, 2014 From top left, cylinders 1 - 4. From what I can tell with the inspection camera, there is still evidence of cross-hatching on all the bores & no broken metal bits. That fluid on top of the pistons you see, is mainly petrol, with a little oil. Cylinders 3 & 4 look healthy, 1 & 2 not so much. Am going to lean out those carbs a touch & see how things go. On a side note, changed my driving style to load up the (chrome, not cast) piston rings a little more & the smoke production has reduced. Update again: Leaned out the idle mixtures on carbs 1 & 2, total air:fuel ratios leaned out 1.0 at idle & 0.5 at full noise. Also dropped the fuel pressure from 2.0psi to 0.5psi, the exhaust now smells less like an oil fire & more like burnt petrol! My 185 main jets may have to go though, will try the 160's instead & see how things go now a few bugs have been ironed out of the fuel system setup. Also stashing these links here for reference, they were a big help. http://www.keihincar.../tips/gate.html http://www.advrider....ad.php?t=624600 Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 29, 2014 Author Report Share Posted March 29, 2014 Feeling a little more optimistic about all of this! Cylinders 1 - 4 from top left, Cylinder 1 is the only 'moist' cylinder now (though it's looking better), the other 3 are looking okay. Going to lean out it's idle mixture screw & see how things go. Thinking I need to go smaller main jets, test-drive will confirm. Yay for data-logging! The shiny bits you see on the intake valve side of the number 3 piston aren't marks from contact with the valves, just carbon-free shiny bits. Checked out the valves with the mirror attachment & they look okay. Spark plug inspection Round 2, things are looking better. Cylinders 1 - 4 from left to right. Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 29, 2014 Author Report Share Posted March 29, 2014 A massive thankyou goes to EvanG for the use of the carb-synch gauge-set. He was right about the 'burble' noise when the throttle is just opened too, so out of synch! The bad news is that I snapped my idle control cable, so things are as good as they can get at the moment. Things sound better too, though number 3 still needs some love, cable ties/clamps on the hoses made no change to the flickering. :( Quote Link to comment Share on other sites More sharing options...
coln72 Posted March 29, 2014 Report Share Posted March 29, 2014 What happened to a piece of hose and you ears.... ;) Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 29, 2014 Author Report Share Posted March 29, 2014 My ears have no clue what is meant to sound good & what is bad, nor what effect turning the screws have exactly. Thus, gauges. :P For example, I thought the burble was a good thing...nope, that was carbs out of sync. :( Fuel figures are getting better, so close to that elusive single-figure mark! Though the throttle feels SSOOOO much better, hauls arse on an on-ramp too. :yes: Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 30, 2014 Author Report Share Posted March 30, 2014 In other good news, haven't seen any oil smoke since yesterdays tuning efforts. Plenty of dust though. Loving the dust, all of the dust! Quote Link to comment Share on other sites More sharing options...
carbonboy Posted March 31, 2014 Author Report Share Posted March 31, 2014 I forgot all about picking up the castor bushes from Fulcrum, they delivered some gear to work today & they were kind enough to drop them off as well. I'll get photos tomorrow, but the standard rear bush for the front control arms has the bolt hole in the centre of it, in these the hole is offset, giving slightly more castor. Probably better for the people with power-steering but *meh* I'll live. When I get the time, going to swap the Main Jets in the carbs as well, these 185-ish jets are just too big, will put the 160's in & see how things go. Managed to track down a replacement idle adjustment cable so that I can finish getting the carbs in sync. Quote Link to comment Share on other sites More sharing options...
carbonboy Posted April 3, 2014 Author Report Share Posted April 3, 2014 I should have just left the ʞ©$ɟing thing alone... Swapped the main jets from 185 to 160, hooked everything back up, after a bit of farting around she started & would idle, but would idle rich as hell (like 10.0:1 rich) & the fuel pressure always read 0 despite any & all adjustment. Not only this, but would rev to about 4,500rpm, then would lean right out out & die. Figuring it was something I touched, I pulled the carbs back off, put the 185 jets back in & hooked them back up. Have 2psi of fuel pressure again, but the same symptoms. Fuel bowl floats operate/seal properly so I don't think I've done something to them. Attempted to get the carbs properly in sync today since it would at least idle for me, not only are they worse than when I started, BT's now blowing a metric shit-ton of smoke. Oil based smoke to boot. Quote Link to comment Share on other sites More sharing options...
carbonboy Posted April 4, 2014 Author Report Share Posted April 4, 2014 For the seventh time in four days, suffice to say I'm getting plenty of practice. Well, buggered o-rings on the fuel bowl inlets sure won't help matters much. Hoping that cleaning the filters out & replacing the o-rings will solve the dramas. Quote Link to comment Share on other sites More sharing options...
carbonboy Posted May 4, 2014 Author Report Share Posted May 4, 2014 One month later.....she works again. So happy right now, may have teared up a little during the test drive. Quote Link to comment Share on other sites More sharing options...
67Rolla-Ken Posted May 4, 2014 Report Share Posted May 4, 2014 Well done! Glad to hear she's back up and running. Quote Link to comment Share on other sites More sharing options...
carbonboy Posted May 5, 2014 Author Report Share Posted May 5, 2014 (edited) Thanks mate, on one hand it's been a PITA, on the other it's been a helpful learning experience. Hoorah for learning! Speaking of running, no more Subaru-burble after getting the carbs in sync-ish but the throttle response is nice. Back to daily-driver duties at last. Edited May 5, 2014 by carbonboy Quote Link to comment Share on other sites More sharing options...
coln72 Posted May 5, 2014 Report Share Posted May 5, 2014 Great to hear your back up and running again :) Quote Link to comment Share on other sites More sharing options...
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