Turbo/Engine testing

[tommin]

Anyone know how to check if the turbo has a problem, like could it be cause of smoky engines? I did read it somewhere that you can disconnect turbo and see how the engine runs? I have not the foggiest idea..... but am not giving up just yet on the old engine.
Regards Tom

[123-jn]

Yes it could be the cause of a smoky engine but there are many reasons for this. What colour is the smoke and when does it appear? after having your foot of the throttle while slowing down when you plant your foot again? or as you accelerate hard? Is there any lack of power compared to normal? Take the inlet hose off the centre of the turbo (inlet) you will see the compressor wheel put your finger on the centre and give it a wiggle. There should be a small amount of play as it spins on a cushion of oil when running but if it is rattly the bearings may be caput, this usually leads to the oil seals being caput and you finding copious amounts of oil in your inlet trunking towards the engine and sometimes back to the air filter. This would cause blue smoke in the exhaust and high oil useage. (note there is always a small amount of oil on the pipe surfaces but not mega puddles.) Other possibilities would be whether there is enough turbo boost as you throttle up lack of this could be caused by a worn turbine wheel on the exhaust side or problems with the wastegate setting or operation. This would cause black smoke under acceleration and lack of power.(caused by unburnt fuel, not enough air to complete combustion). This is difficult to measure without the correct gadgets. (a boost gauge). If you disconnect the inlet trunking from the turbo it will run pretty much as if you have low boost. I once towed my caravan back up the M5 from cornwall after the inlet hose had split between the turbo and the manifold, 20 mph up hills and black smoke like you have never seen. I tried a repair with gaffer tape but the pressure ripped through that also and we were back to square 1. (LDV PIlot 1.9 TD)
Good luck

[tommin]

Thanks for the response and some valuable information. I put my issues on an earlier post, cut long story short. Vehicle died during a trip, got it started but smoking bluish black, not bad on tick over but as soon as you accelerate it pumps it out. Power is okay, drives okay just real bad smoke! I had an issue with the fuel pump way back, started to leak so replaced seals worked fine, then another leak came and decided to change pump. Done all the right timing etc... tdc pump aligned, set pump timing to 1 as advised tried everywhere between 0.8 and 1.2 to see if it would rid the smoking but no joy. Starts first turn runs but smoke is way off the charts? This is why I was question the turbo?
It is winter here with a ton of snow sitting on the van at the moment, so cannot do much until the thaw, except gather as much help advice or information that could help me. I appreciate any and all given.
Regards
Tom

[123-jn]

Does it smoke that bad even when revved out of gear? Usually with a turbo failure it smokes much worse under load and less if stationary? Sounds rather more like fuelling but If I am right it was doing this before and after the pump swap? Does it reduce as the engine warms up at all? I think I would start by looking for mega amounts of oil in the inlet and turbo (compression side) . If this is not the case I would find a friendly mechanic to attach a boost gauge to the turbo and check you have the right amount. I don't know the actual figure but would guess about 0.8-1bar. The wastegate could be stuck open if it is low. If this is all ok then as it starts straight up I would assume compression is at least ok and point my finger at the fuelling as long as you are sure the pump timing is ok. It is sometimes worth leaving the bolts for the pump loose and after starting the engine move the pump on its bracket to try the timing more advanced and see if the smoke disappears (is the belt definately on right and will all the timing pins go in?) If a bit of advance doesnt work you are left with taking the pump off to have it looked at before which I would pop the injectors out and clean the business end or entrust it to someone who knows how. (one little dribbly injector can cause untold smoke.)

[tommin]

It smokes not so much at ticker but it is still more than it used to be. I when i rev it smokes like heck and if i give it full throttle the blueish grey turns to black!!!! I pulled all the injectors, stripped down and cleaned all parts, there were some crud there but still the smoke persists?? No problem with pump and pins! I will try the loose pump method when I dig her out of the snow

[tommin]

Well winter finally passed, fishing season just started but am keen to get the old girl right. It started after a couple of turns which am happy to report, not bad after sitting since last October

To day I brought her round to the yard smokey as ever which put me back in a downer!!!!! So I got underneath and started to see where to next. I pulled the air intake off from the air filter to turbo and got covered in oil

A full mug full darn..... So with a few choice words and ripping my oil soaked work coat off and flinging it, decided to just clean up the mess and ponder the What the blithering heck is going on conundrum .... I tested the spindle and it is firm very very limited movement in any direction.. I think I need a cuppa and time to research this, so forgive my woes, just a bit of therapy putting my thoughts into words...