Diesel in the Oil? Newbie advice needed

.:SAmSuNG:. · 25 Mar 2017 at 18:26

So had a 2010 Astra 1.7CDTI A17DTR for about 7 months now but recently my wife had the DPF light come up as it normally just tootles round town. I took it for a bit of a blast on the Autobahn in 5th at about 3k Rpm to try give it a clear out.

Suddenly there was a load of what looked like white smoke and the one end of the engine making a nasty banging noise like two hammers been hit together. I had it recovered and read the ECU which gave a fault with one of the injectors.

I removed all the injectors for a look at the ends and refitted them along with a different used injector with the old copper injector seals. The car ran without the nasty noise but was still smoking abit and after a short drive I checked the oil to find it had risen with lots of Diesel in it.

Last week i refitted the injectors after giving the face of where the injector meets the head a good clean and fitting new copper seals and also changed the oil. Now it ran as it should with zero smoke or noise but again I checked the oil and it had diesel in it again. Ive read the ECU and it now has zero fault codes.

I want to try and figure this out myself before paying someone.

My next plan is to compression test it through the glow plugs leaving the injectors in place which im guessing will not only test the rings but also the injector seals?

Ive never compression tested anything but ive read they should read about 370psi for this engine. Im hoping it may atleast narrow it down to say a certain injector not sealing properly.

Does this sound like a good move to make to rule out piston rings before I go and pull the cam cover off again and have the injectors serviced at £400?

Thanks

Orionaut · 25 Mar 2017 at 23:10

Diesel in oil normally is a consequence of multiple failed regens

(Modern diesels, dont you just love them. see other thread

)

First thing I would have done is drain and change the oil rather than dive into messing around with injectors, there comes a point with fuel contamination where oil can end up passing through the crankcase vent system and end up being burned as fuel.

This can not only cause bad noises but also multiple irrelevant fault codes and ultimately "Diesel Runaway" (Google it, It is fun!

)

Edit to add.

Third Google link down when I just did it has a nice Youtube link for diesel runaway.

The trick is to stuff something into the air intake to suffocate it, But you do need to be wary, there is a real danger that the engine might explode and kill you!

NickK · 26 Mar 2017 at 13:04

The only way you get diesel into oil is at the cylinder - specifically the cylinder rings.

The old big diesels look like fun with a runaway.. but not something I'd want trying to stick to 30mph down the street Officer my engine ranaway!

EDIT: CO2 firextinguisher trick

Then the quickest method to shut the engine off is to use the CO2 fire extinguisher you normally carry in your car. Grab it, pop the hood and spray right near the intake. It helps if you know which one that is before. If not, spray everywhere. The CO2 will replace the air needed to burn the fuel which should stop the engine.

chaparral · 26 Mar 2017 at 13:07

Orionaut said:
But you do need to be wary, there is a real danger that the engine might explode and kill you!

I would also worry about breathing in loads of smoke from a diesel runaway engine if you were try to get close enough to stop it..

.:SAmSuNG:. · 26 Mar 2017 at 15:21

NickK said:
The only way you get diesel into oil is at the cylinder - specifically the cylinder rings.

The old big diesels look like fun with a runaway.. but not something I'd want trying to stick to 30mph down the street Officer my engine ranaway!

EDIT: CO2 firextinguisher trick

How is it the only way? The injectors are underneath the cam cover meaning the are part outside the engine, part in the engine where the cams are and part in the cylinder. If the injector seals were faulty this would allow the high pressure of whatever is in the cylinder into the oil.

I'm not worried about this runaway the car won't be driven until oil is dropped again. I was hoping that someone may know if a compression test would test not only the rings and valves but the injector seals also?

NickK · 26 Mar 2017 at 15:32

.:SAmSuNG:. said:
How is it the only way? The injectors are underneath the cam cover meaning the are part outside the engine, part in the engine where the cams are and part in the cylinder. If the injector seals were faulty this would allow the high pressure of whatever is in the cylinder into the oil.

I'm not worried about this runaway the car won't be driven until oil is dropped again. I was hoping that someone may know if a compression test would test not only the rings and valves but the injector seals also?

Gotcha - the injectors I've seen are outside the oil loop.

.:SAmSuNG:. · 29 Mar 2017 at 18:04

Right bit of an update.

Got a compression test kit and tested it by removing the glow plugs and fuel pump relay.

All cylinders hit 390psi and held steady. The glow plugs have seen better days so I ordered a new set.

After abit of research I have ordered some fuel leak dye which should rule out the injector seals leaking.

In the mean time I'm going to remove the fuel leak off hose to make sure it's free from blockages.

If both of these points above are fine and after doing a compression test I can only think I need a new set of injectors.

What do you guys think?

J4G3D · 26 Aug 2019 at 13:10

.:SAmSuNG:. said:
Right bit of an update.

Got a compression test kit and tested it by removing the glow plugs and fuel pump relay.

All cylinders hit 390psi and held steady. The glow plugs have seen better days so I ordered a new set.

After abit of research I have ordered some fuel leak dye which should rule out the injector seals leaking.

In the mean time I'm going to remove the fuel leak off hose to make sure it's free from blockages.

If both of these points above are fine and after doing a compression test I can only think I need a new set of injectors.

What do you guys think?

Hi mate,
Did you get to the bottom of this issue? I found this thread via google (apologies for those that hate old threads getting resurrected).

I also have diesel getting in the oil with the exact same car, year, engine. Well.. I THINK its diesel, it seems to be thinning the oil and its rising, so one can only assume its diesel. Also got smoke and the smell of oil from the tailpipe. obviously the worry is its the piston rings gone! So before declaring the car scrap, I'd want to rule out injector issue too, which surely could be the culprit in my/your issue. One thing, if I remove the fuel pump relay, the car still starts and runs as it should. Very odd?

I have a set of injectors and washers that I plan to replace. I just don't know how to do it, Obviously the rocker cover comes off, but not sure if any special tools are needed to lift the injectors. I do have the tool to program them in though (thats my area of field more than mechanical work) On the new injectors it seems that the return hoses attach to the top with what possibly could be a circlip (I don't have pliers to remove that!). Anyway, any advice on that greatly appreciated. Also a update on your vehicle.

Nasher · 26 Aug 2019 at 14:02

At least if diesel runaway happens on the motorway at 80mph it will be a memorable death, in a huge loud fireball