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| Thread ID: 118745 | 2011-06-19 02:17:00 | Any Mechanics here? | hueybot3000 (3646) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 1210503 | 2011-06-19 11:00:00 | Yes if id known what I found out today earlier I wouldnt have gone to the extents I have in disassembling the engine bay! But I will give everything a clean up anyway while its apart, and hopefully find some rubbish valve seals | hueybot3000 (3646) | ||
| 1210504 | 2011-06-19 11:18:00 | Yes if id known what I found out today earlier I wouldnt have gone to the extents I have in disassembling the engine bay! But I will give everything a clean up anyway while its apart, and hopefully find some rubbish valve seals No product will clean the intake up properly, it's best to take it apart and give it a good clean anyway. And they have a metal head gasket don't they? So no problem with pulling the head off (no need to replace the gasket). |
ryanjames.powell (13554) | ||
| 1210505 | 2011-06-19 11:26:00 | If it is valve guide seals it will smoke on start but once running the smoke will stop. In the old days they didnt even try to seal the valves for leakage just accepted some oil would statically drip down inside the head. No need to clean the soot or oil in the manifold just fix its root cause. There is no such thing as mechanic in a can these things do more harm than good. You might have a cracked head not sure if that sort of motor you have is prone to cracking. Its good that you are investigating the cause of the smoking and misfiring an inquiring mind is a good thing and will hold you in good stead thru out life. |
prefect (6291) | ||
| 1210506 | 2011-06-19 11:40:00 | Sounds like time to try some of that Wynns stuff, if they still sell it. Cleans the bore and combustion chamber etc. What the heck, sometimes simple solutions work. Or run some avgas through it just to run up the rev range. :D Actually the carbon can act as an oil seal and if you remove it will smoke worse. |
prefect (6291) | ||
| 1210507 | 2011-06-21 08:38:00 | If it is valve guide seals it will smoke on start but once running the smoke will stop. In the old days they didnt even try to seal the valves for leakage just accepted some oil would statically drip down inside the head. No need to clean the soot or oil in the manifold just fix its root cause. There is no such thing as mechanic in a can these things do more harm than good. You might have a cracked head not sure if that sort of motor you have is prone to cracking. Its good that you are investigating the cause of the smoking and misfiring an inquiring mind is a good thing and will hold you in good stead thru out life. Mine didn't stop smoking until it was well and truly warmed up (100km/h for half an hour or so). And if it idled for a while it would then start smoking again. Also, the soot in these things actually builds up to the point where it noticably inhibits performance due to air intake restriction, so cleaning it out is a good idea. |
ryanjames.powell (13554) | ||
| 1210508 | 2011-06-21 09:51:00 | Those symtoms are almost an exact description I got from the guy. Idling was definitely something he mentioned again and again. I actually wish Id kept the car together longer and looked more into now | hueybot3000 (3646) | ||
| 1210509 | 2011-06-21 10:46:00 | Just wandering if the throttle body is dirty as well, might need a clean. Maybe the ventilation valve (EGR I think it's called) system as well. Maybe the air flow sensor. This has caused missing at Idle from cars I fixed. Cleaned it's filament with electrical cleaner, which was dirty with oil mist/gunge. Other missing problem was from dirty contact/cam angle sensor in the distributor - oil got through past the shaft seal. But generally on engines over 15 years use or higher than your 170, 000 K's. Then again, if engine has not been serviced routinely... | kahawai chaser (3545) | ||
| 1210510 | 2011-06-21 11:26:00 | Engine has been serviced regularly by the same mechanic for the 8 years the previous owner had it. The throttle body is very sooty on the out side of it. The miss was over the entire rev range, almost like a coil was dying. But the plugs were also very oiled up so that wouldnt help. The whole thing is a bit hard to diagnose when u have no experience with japas haha And everything will get a very good clean before it goes back together! Will know more when I pull the head off in the morning Cheers guys |
hueybot3000 (3646) | ||
| 1210511 | 2011-06-21 15:29:00 | Ya know it's pretty easy to tell if it's guides/seals or rings - right? No gauges, compression tests or other diagnostics involved - but you smell the exhaust. Oil going through combustion by getting into the cylinder before the fuel is ignited, will smell sweet and rather pleasant even. Oil going down the valve stems past the seals - and this is almost always on the exhaust valves - will smell sharp, acrid, and even make your eyes water if it's concentrate enough. Not sure on your Mitsubishi, but some use precombustion chambers and those valve stem seals are notorious for leaking and causing excessive blue exhaust smoke. PC Chambers are rather old school though and not so prevalent in the US - so I'm out on a limb here with whatever you might have in Upsidedown Land. Is it turbo'd? Turbo chargers can also have internal seal failures and they can pass oil into the engine in quantities enough to smoke out the tailpipe and also at the same time coat the inside of the plenum to cause such deposits to collect there too. Then either with or without a turbo, the EGR picks up the exhaust and redirects it back into the plenum to get consumed inside the cylinders to quench cylinder stoichemetric temperatures to keep NOX from forming. Use you nose first and you might not have to tear the whole engine apart. |
SurferJoe46 (51) | ||
| 1210512 | 2011-06-22 00:29:00 | Might also want to see exactly when smoke occurs for a cold start - right after fire-up - or say 30s to a minute after. This might indicate (should not really on 170 k) worn oil control rings that have lost their springiness and also might be a bit rigid with gunge on them. I think the bore might expand faster than worn rings or rings not expanding fast enough. Hence no smoke directly after cold start, but shortly after -since a gap occurs (rings not fully expanding/releasing properly or fast enough) - thus smoke becomes evident because of a gap. Then when fully warmed or when cruising, the rings then gradually take up the gap - hence no smoke. Then compare when smoke occurs (if any) on warm start up. Not sure what happens, why smoke occurs during warm idle - this could point to worn seals. But worn seals as noted by prefect, can cause smoke on start up. This might occur instantly after fire-up. For engine miss, perhaps do resistance tests (need specs to compare) on the coil. Also resistance test the power transistor (ignition module), which connects to coil from ECU. After standard plugs/lead cleaning/resistance tests. Of course a diagnostic scan will show codes and any ignition faults, if not cleared, e.g. by battery removal, or number of start cycles, etc. |
kahawai chaser (3545) | ||
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