diesel runaway prevention or divorce !!

[zak]

Ok four months on from my diesel engine runaway drama I'm no less paranoid about it happening again. My wife genuinely hasn't been in the van since !! Maybe its me she's avoiding ??
It was a very dangerous situation and destroyed the engine. Runaway is a rare thing thankfully but I do need to come up with a solution to stop the engine if it were to happen again.

Cue install petrol engine jokes . . . . . .



The probably obvious answer is to fit a standard EGR and its vacuum Anti Shudder Valve ASV (or inlet manifold flap) but the plumbing of the standard and long EGR would be difficult. I also dont really want the EGR. People also say just put it in top gear, brake and dump the clutch etc. – trust me that did not work.
Access to stuff a rag in the inlet as many say is also just not feasible. And do I really want to jump out in the traffic with the engine screaming and dump a fire extinguisher in the inlet. The damage will have been done by then.



In hope I bought an electric ASV from a later Tdi (part 038 128 063 L) but the bore was too small. The stand alone ASV's are shorter and would plumb in easier. I'm also not sure about the electrics, that one had four wires. (negative, positive, position out, control in - I think ??).

Anyone know a short body ASV model that is 57mm bore please???

Anyone know more about the electrics of it that they can share please?




The shorter electric ASV seems to default to open which is not ideal for runaway purpose. Maybe this could be fixed with the correct voltage supplied on the control line ?

The bolt pattern will probably be wrong for the inlet manifold but an alloy adaptor plate should be do able.

I'm researching other intake shut off valves but so far they are bloody expensive.

The Pacbrake PH3 is really neat and can be vacuum, electric (even from over speed on crank position sensor) or cable operated but $1000 plus shipping, duty etc !!!!

http://pacbrake.com/valving-solutions/a ... rhalt-ph3/

Or the

D57-57mm, from DESS (Diesel Engine Safety Solutions) (price is £381 + VAT ) and operates on preset airflow rate when over revving.

http://www.chalwyn.com/tenants/chalwyn/ ... /CE204.pdf


Re the runaway that happened, I dont really know why it happened. It was a newly rebuilt engine and turbo (by a garage), it had done 700 smooth and sweet miles until Diesel hell unleashed itself. The end of the glow plug by the piston above was burnt off. I suspect it was more of a diesel runaway than engine oil as it stopped on its own eventually. But there was black engine oil spat out of the exhaust and around the turbo so it had run on engine oil. Apparently there was diesel in the engine oil when it was stripped so maybe it was a faulty injector or seal.

I really dont want to experience that again or wreck the replacement engine

Any help before marital runaway greatly appreciated

[lloydy]

if you go on the darkside developments website, they do egr delete pipes that allow you to keep the asv. You'll then just have to sort out the pipework, can't really see another option without custom making something. And custom stuff always seems to lead to other problems.
http://www.darksidedevelopments.co.uk/e ... and-parts/" onclick="window.open(this.href);return false;

[zak]

if you go on the darkside developments website, they do egr delete pipes that allow you to keep the asv. You'll then just have to sort out the pipework, can't really see another option without custom making something. And custom stuff always seems to lead to other problems.
http://www.darksidedevelopments.co.uk/e ... and-parts/" onclick="window.open(this.href);return false;

Thanks Lloyd, I've called and messaged them a few times and specifically asked about this, but the people I spoke with can't seem tell me which ASV is 57mm bore. Someone I spoke to there told me the only way was to fit the standard EGR.

As far as I know the standard PD130 ASV is integral in the EGR and vacuum operated. I'd prefer something more like the pic I added but still have to sus out the electrical side so that its suitable for runaway shutdown. There's not much room for any additions on inlet in my current setup.

[syncroandy]

Connections to V157 intake manifold flap motor:

1 - Earth
2 - ECU
3 - ECU
4 - 12v power

Assuming its just a simple solenoid or motor inside not something fancy like a stepper, a simple way to check its function would be to wire it up using a pigtail, provide earth and power, and then simply put earth/12v on pins 2 &3 until you suss out its behaviour. Then wire up accordingly using the vans ignition terminal and a relay if required.

Regarding defaulting to open, agreed you don't want to wire it up in way its using current when the ignition is switched off. You may want to check the behaviour of your engine current supply relay output (terminal 87a) its possible the ECU keeps this on for a short period after engine shutdown, so you could use that for power (this is how it is on the original car).

PS. Or possibly use the ECU control signal for the original ASV control solenoid valve.. ? There's gotta be way to do it..

[zak]

Connections to V157 intake manifold flap motor:

1 - Earth
2 - ECU
3 - ECU
4 - 12v power

Assuming its just a simple solenoid or motor inside not something fancy like a stepper, a simple way to check its function would be to wire it up using a pigtail, provide earth and power, and then simply put earth/12v on pins 2 &3 until you suss out its behaviour. Then wire up accordingly using the vans ignition terminal and a relay if required.

Regarding defaulting to open, agreed you don't want to wire it up in way its using current when the ignition is switched off. You may want to check the behaviour of your engine current supply relay output (terminal 87a) its possible the ECU keeps this on for a short period after engine shutdown, so you could use that for power (this is how it is on the original car).

PS. Or possibly use the ECU control signal for the original ASV control solenoid valve.. ? There's gotta be way to do it..

Thanks Andy, very useful and positive. If i can just find an ASV at 57mm bore I'll take the plunge and have a go. Hopefully one exists.

I stumbled across this doc for a BRM engine and it has a bit of info on the Inlet Manifold Flap (or ASV or V157). Pages 20 and 29 and a few other places. VW don't seem to mention its use as a runaway device. That one has 5 wires. It does say when the engine is switched off the flap is shut. But also that it is held open by default via a spring.

https://www.dropbox.com/s/p4yp6jj6t4ryq ... 9.pdf?dl=0

Lloyd unfortunately Darkside don't have a double flange EGR delete pipe at 57mm.

[clift_d]

Ok four months on from my diesel engine runaway drama...

Holy smoke! Was that your shiney TDi? Dare I ask what 'the installer' had to say about that?

[zak]

Holy smoke! Was that your shiney TDi? Dare I ask what 'the installer' had to say about that?

They were every bit as gutted as me. Was a real shame, that engine was sweet. Everybody lost on that job

[busbuddy]

I suspect it was more of a diesel runaway than engine oil as it stopped on its own eventually. But there was black engine oil spat out of the exhaust and around the turbo so it had run on engine oil. Apparently there was diesel in the engine oil when it was stripped so maybe it was a faulty injector or seal.

just thinking out loud like but....

if the runaway was being fuelled by diesel, via faulty injector/seal/etc, then wouldn't the fuel cut off valve instantly shut that situation down with a turn of the key?

i was always under the impression that a runaway was caused by combustibles such as oil or other dense vapours encountered in the intake air which cannot be controlled by the fuel shut off valve, a runaway on oil would die eventually as you describe because the oil runs out and there is so much damage that diesel would easily find itself mixing with oil in the sump

did you have the oil breather feeding into the intake, was the sump baffled....i'd be inclined to think oil was the problem

[zak]

I suspect it was more of a diesel runaway than engine oil as it stopped on its own eventually. But there was black engine oil spat out of the exhaust and around the turbo so it had run on engine oil. Apparently there was diesel in the engine oil when it was stripped so maybe it was a faulty injector or seal.

just thinking out loud like but....

if the runaway was being fuelled by diesel, via faulty injector/seal/etc, then wouldn't the fuel cut off valve instantly shut that situation down with a turn of the key?

i was always under the impression that a runaway was caused by combustibles such as oil or other dense vapours encountered in the intake air which cannot be controlled by the fuel shut off valve, a runaway on oil would die eventually as you describe because the oil runs out and there is so much damage that diesel would easily find itself mixing with oil in the sump

did you have the oil breather feeding into the intake, was the sump baffled....i'd be inclined to think oil was the problem

Thanks for that, I dont know enough about diesel engines to say either way. Its a PD (pump duesche) Tdi so I'm not sure how the fuel cut off happens as the injectors themselves are the diesel pumps driven by the camshaft and the fuel is fed to them by the tandem pump also on the camshaft. I do plan to also fit a fuel shut off solenoid before the tandem pump.
After the runaway the dipstick was still on its upper mark, but the engineer said the sump oil was a good mix of engine and diesel when he drained it.

The oil breather IS into the turbo intake pipe. I have noticed the intercooler pipework is oily inside. Maybe that's why people fit a catch can instead??
There are two baffle plates in the sump, not sure how that's relevant, have I misunderstood you?

[busbuddy]

i believe the ecu tells the injector to stop on the pd when the power is cut off so i assume the runaway cant just suck diesel through on its own if the ecu knows the key has been turned


baffle plates help to stop the oil surging around too much when the engine is over at 50 degrees rather than 15....i assume yours is over at 50 ?

the asv is as far as im aware just an item to help the engine stop nicely for customer pleasure rather than an essential item so i would think the basic diesel cutoff would be a designed 'un-failable' element which would always fail to the shutoff position

i'm assuming the pd has the same ecu programming that kills the revs, diesel fed to engine, if the brake/clutch is stamped on? its how it could get diesel into the inlet by itself that is puzzling me, could the tandem pump fail leaking diesel into the sump which raises the oil level far enough to cause the engine to start sucking in the heavy vapour now present in the breather pipes?

very odd