Thread: Diesel engine problems

You reminded me of another mod I did to the Trytoo.That pcv valve,firstly I just let the hose hang down the engine bay.It was creating a mess so I plumbed it into the chassis rail.Never seemed to drip excessively,BUT we lived at the end of a 15km gravel road Guessing the dust stuck to it,got washed out in winter/after beach fishing chassis cleans.
Andrew

Hello again. just a sigestion here before spending any more money. Take a step back, and think about what's going on.. There's a reason the thing stopped in the first place. Thats where you start. The second turbo is now toast... The engine is running hot, and lacking power.. You don't need a turbo on that engine to make it run. Loose the turbo for now, cap the oil supply and return, and look to why its not running correctly. Oil pressure.. Put a mechanical gauge on it. What's the PSI reading when cranking, when running cold, when running hot? As someone else said, is the oil PRV jammed. Too much pressure can do harm too... Turbo seals, hydraulic followers forced open too far causing valves not to close etc (bends valves causing misfire and marks the top of the piston)... If the oil pressure is normal, move on. If not, find out why.... Timing... Start again with this, as per book. All marks must line up. Crank to cam, fuel injection pump etc.. This is critical to a diesel. Once done, check it again having rotated the engine at least 360 deg by hand first. Moving on.. If it is holding its coolant and not loosing any, great. No cracks! Good to hear. It still got hot.. So we now continue looking for the cause... Viscous fan.. Is it loose and does it spin freely? It shouldn't . There should be resistance... If its loose its knackered. Thermostat... Remove it and check it in a saucepan of water. Record its opening temp and see if it matches the number stamped on it. Do NOT leave it out! Next, radiator.. Check the core. Remove the rad if you have to and flush it properly.. Good flow? Great. Next.. Water pump. How's it driven? Cam belt or fan belt? Does it feel ok? Is it actually working? Has the impeller fallen off??? (Stranger things have happened..). All good? Hoses.. Has one collapsed internally? Is the heater supply ok or air locked? Moving on.. If the cooling system is good, the next heat cause is over fuelling or lack of air.. Is the air inlet clean? Intercooler pipes? Any rags left in there? Sounds silly, but follow the path the air takes and make sure there are no delaminated hoses or obstructions. This brings us back to timing and fuel amounts.. Have you had the injectors out? If not, do so. Remove them, invert them and reconnect the high pressure line to each injector.. Stand back and get someone to crank the engine. What are the spray patterns like? Should be a uniform spray from all.. A very fine mist (atomised fuel). Any drips, jets or squirts? If so they're knackered. (Take heed here. Atomised diesel under high pressure is very dangerous. Can't empathise this enough. You are viewing spray patterns only, from at least a few meters away. This is not the ideal way to test, but it does mean you can do it and don't have to pay someone to do it and then tell you that they're shagged). Injectors ok? Cool. Refit. So, now we've covered fuel, timing, cooling, air supply, oil pressure, there's not too much left. If you have done all of the above correctly, it should fire up. Crank it over with the fuel pump wire off. Does it sound even? If not then there's a compression issue. If it does, great. Reconect the fuel pump wire. Does it now fire up? If yes, what does it sound like? Smooth? Rough? Misfire? Colour and amount of smoke out of the manifold? If its running, and running nicely, monitor the coolant levels and pressures. Monitor the oil pressure. Let it idle, bring it up to temp. That'll keep u busy for a while..

Cheers. The only part of that i dont understand is the injector test you've described. Ill start ticking through that list over the next week or so. Thanks for the advice

A while back when I still lived in the UK, if we were working on a tractor 'on site' that had a fuel problem.. Knock, misfire, overheating etc, one of the things that was checked was the injectors. We used to undo and remove the high pressure line to the injectors, then remove the injector (two nuts on studs with Perkins etc). Once out and after a visual check, the injector was then reconnected to its high pressure supply line, but facing out of the engine not into it. The engine was cranked and each injector watched to see that it was atomising and spraying correctly. Its not the ideal way of testing them, nor is it normally recommended, as high pressure atomised diesel is dangerous in close contact, and very flammable. It is however a way of testing the injectors without having to send them away and spend money... especially when working on an engine with an unknown problem. Be mindful that the tip of an injector is very finely engineered , and should be treated like a halogen globe.. Not touched, not dropped, not rested against anything etc etc. have a look on YouTube at diesel injector testing, spray patterns etc. you're looking for a very fine spray, no jets of fuel, no dribbles etc..

I understand now. When you said invert them it confused me. All makes sense though.

Car has low oil pressure, so I decided to bin it. An oil pump, plus all of the time and other bits to fix it, and then, not really know what other damage has occurred I have let it lie.

Thanks to everyone for the help.