Diesel running rough and hot

Alternative power-plants and transplants (GTi, Porsche, Subaru, Audi, diesel etc). Discussion and Q&A last answered over 2 years ago.
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psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

Good thinking kap :ok I'm at work all day tomorrow, but I'll try that on Monday morning before I trot off to the Gulag :)
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kap
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Re: Diesel running rough and hot

Post by kap »

Good luck im hoping it is just a falty injector. :D
Sounds like a golf

footstuck
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Re: Diesel running rough and hot

Post by footstuck »

hey mate
did you get the washers that sit under the injectors in the right way up
and get them back one in each hole with correct tightening torque?
Sometimes the simple things can be overlooked
the ones that are Hot might have Hot exhaust gasses passing up the side
making them overly hot and produce a horrible Clacking noise
causing reduced compression and your white(un-burnt fuel) smoke and . . .
out of balance vibration

psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

Thanks Footstuck - I'm going to try and get chance to check that today. I paid particular attention to get them all in the right way, but like you say, it's always worth making the simple and easy checks!! :ok
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Not all of them are peaceful...."

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kap
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Re: Diesel running rough and hot

Post by kap »

How are you getting on with the injectors?
Sounds like a golf

psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

I haven't had chance to have a look at them yet kap, and I'm leaving for work in just over an hour so I guess it'll be tomorrow now. I was going to have a look this afternoon, but just ran out of time..... :roll:
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psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

Hi all :) Okay, so I've had the injectors out this morning and checked all the heat shields - they were all in the right way, but it was worth a check. It does look like she is over-fuelling though, so I need to investigate why that might be.

This is possibly a very stupid question, but I'll ask it anyway - do the fuel return pipes from one injector to the next need to be connected up in any particular way? I have just piggy-backed from one injector to the next using whichever take-off on the injector was closest to the next injector, if that makes sense. Is one set up as an "in" and one set up as an "out"? If I had those the wrong way around then there definitely would be an over-fuelling issue!!

Thanks again boys for any advice :ok
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Not all of them are peaceful...."

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ewenmaclean
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Re: Diesel running rough and hot

Post by ewenmaclean »

Hello again,

that's right - normal route is blank off no.1 and piggy-back until no.4 and then back to the pump.... hope you figure out what it is soon...

Ewen

psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

Thanks Ewen - I'm going to go and connect up the return pipes up and fire her up again and see what happens....
"There are many paths to redemption.
Not all of them are peaceful...."

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For more unchartered heights of disgrace just ring 07872 069462

psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

I officially give up. Still got white smoke, and I've taken each return pipe off in turn and there's no fuel coming back through any of them, even with the engine under load. I'm happy the pump is clear of air, and as I crack each injector in turn I'm getting plenty of fuel coming through, so something is stopping the excess furl returning, but I don't know what. Time to call a man I think :(
"There are many paths to redemption.
Not all of them are peaceful...."

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ewenmaclean
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Re: Diesel running rough and hot

Post by ewenmaclean »

sorry to hear about your troubles. I don't know, but if you've got no fuel returning it could be leaking injectors... seems odd though if they were ok before.... maybe worth taking them to a diesel specialist to check out and balance...

good luck - hope you get it sorted

Ewen

psychonaut
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Re: Diesel running rough and hot

Post by psychonaut »

Thanks Ewen - I had them cleaned and balanced while they were out last week, so I'm happy that they are ok. Something very weird going on....
"There are many paths to redemption.
Not all of them are peaceful...."

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For more unchartered heights of disgrace just ring 07872 069462

psychonaut
Posts: 883
Joined: 07 May 2009, 09:17
80-90 Mem No: 6751
Location: Cardiff
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Re: Diesel running rough and hot

Post by psychonaut »

If there is a mechanic close to, or in Cardiff, that fancies coming and having a look, drop me a PM or call me on 07872 069462. Happy to pay a decent mechanic to get it sorted once and for all - I'm all out of ideas myself :roll:
"There are many paths to redemption.
Not all of them are peaceful...."

Click here for some Visionary 'Nauts.....

For more unchartered heights of disgrace just ring 07872 069462

psychonaut
Posts: 883
Joined: 07 May 2009, 09:17
80-90 Mem No: 6751
Location: Cardiff
Contact:

Re: Diesel running rough and hot

Post by psychonaut »

Well, I've finally got to the bottom of the problem. I decided to take out the new heat shields again and compare them to the old ones that I'd taken out. Indeed, there are some subtle differences, but not enough to cause injector blow-by. When I took out no.2 injector though, I noticed a dirty great crack in the injector seat. Closer examination revealed an equally big crack in no.1 injector seat. Deep joy - looks like I'm looking for a new top end then....

Can the head be replaced with the bottom end in the van, or is it an engine out job?

To say I am pished right off would be understatement of the century.... :evil:
"There are many paths to redemption.
Not all of them are peaceful...."

Click here for some Visionary 'Nauts.....

For more unchartered heights of disgrace just ring 07872 069462

kap
Posts: 740
Joined: 25 Jan 2011, 19:57
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Location: glos/worc. now moved to newzealand

Re: Diesel running rough and hot

Post by kap »

Im sorry to hear that,what a nightmare, would it be easier to change the whole lump? I think I saw a 1y on here or the yard for under £250 then sell of the spares. :ok
Sounds like a golf

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