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bluebedouin
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Diesel knock?

Drove up to Liverpool on Friday for the weekend.No problems,van purred.(Well,sort of)Did a bit of shopping in it on Saturday then Sunday took it to Crosby.Again no probs.Didn't use it Monday & when I started it on Tuesday to come home there was a nasty metallic knocking from the engine.It stopped after a while so i drove it round the block to warm up & all was okay.
Got onto the M57 & at about 45mph it came back but not so loud.pulled off at the first exit & called the breakdown.When he arrived it didn't make a sound so he suggested I take it steady (what else can you do in a beddy?!)& should be okay.
Back on the motorway,merged with the M62 just past the off slip to junction 7 it starts again.Pull on to the hard shoulder call breakdown again.Bloke comes out (different one)listens to engine,no noise!
Puts us on the back of the truck anyway & takes us to Burtonwood services where it's quieter to have another listen.By this time Autohome have authorised a full recovery to Northampton.
He takes us as far as Hilton Park Services & there we get picked up by a Northampton guy.When we get home I start the engine & lo & behold the knocking's back.He made my day by saying,"Sounds like a big end going to me".
I went out this morning to video it to get the sound &,guess what?Yep sweet as a nut!
So.until I can get a recording,anyone got a suggestion?Is it an injector,sticking valve,tappet/push rod or big end?

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Wed 06 Mar 2013 @ 20:52 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
Bob Hillier
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Sorry Graham! Been there, done that. Big Ends Mate. I won`t get technical and confuse you (and probably me!), but it`s engine out and put that Merc diesel you`ve been saving,

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We don`t stop when we get old, but get old when we stop

Thu 07 Mar 2013 @ 05:35 View Bob Hillier   Email Bob Hillier   Edit this messageQuote this messagePMQuote this message
Anon
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Knocking.

Hi to all,

I have found this problem before, in one case the air intake had picked up some debris from outside and sucked it into the cylinders, on the other knocking noise it turned out to be a partly choked oil pickup pipe mesh in the sump.
If it is in the sump when you switch off the piece of debris floats back from the pickup mesh and the knock stops, in the case of the air intake the debris can move away from the crown of the piston and the knock will fade.
If it is in the sump an oil pressure gauge will show a drop in the gallary pressure, in the case of the air intake this only happens when the air intake is very low down at the front of the motor.
I hope this helps and don't have to take out the engine for repair.

Doug.

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Thu 07 Mar 2013 @ 10:37 Edit this messageQuote this messagePMQuote this message
bluebedouin
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Thanks for the comments chaps.Bob,if it were the big end(s)wouldn't it be a constant noise?I had an old moggy thou' that had that problem & the only time it was "quiet" was when I let off the accelerator!
Doug,I don't have a pressure gauge so I can't check that.As the noise is intermittent it does sound a possibility though.The air intake is at the top of the engine so I can probably rule that one out.
I recorded the engine this morning & although it does sound noisy,that isn't the rattle I'm talking about!

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Thu 07 Mar 2013 @ 11:22 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
Anon
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hi graham

Suggest new radio turned to full volume

John
Thu 07 Mar 2013 @ 16:39 Edit this messageQuote this messagePMQuote this message
bluebedouin
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Thanks for your carefully thought out reply,John.

Just went out again but still not playing ball.The closest I can find so far on the internet is this one,but louder.

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Thu 07 Mar 2013 @ 17:33 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
Anon
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The knock.

Hi again,

Having listened to your sound recordings the noise is definatly at piston speed
and my money would be on a bigend knock, on most diesel engines the first bigend shells to ware are on number four cylinder, least oil supply and lowest pressure.
(Why would the noise go away and then return?)
Because the bigend shells have worn thin enough to rotate on the crankshaft journal and has thick and thin area's of shell as it turns around the crank journal so knocking then after a rest and colder oil the knock fades away.
But once the engine heats up and the oil thins down the worn shells are able to move round and the knock get louder.

Doug.

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Thu 07 Mar 2013 @ 20:07 Edit this messageQuote this messagePMQuote this message
Bob Hillier
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There you are Graham, Shells get thin and float when heated, causing the intermittency (is that a word?). Had that all the way from Scotland on a Commer pop-top in the eighties. Used up seven AA patrolmen on the journey, but still got home.

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We don`t stop when we get old, but get old when we stop

Thu 07 Mar 2013 @ 22:16 View Bob Hillier   Email Bob Hillier   Edit this messageQuote this messagePMQuote this message
bluebedouin
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Mr D.S.Joyce. wrote:
....
after a rest and colder oil the knock fades away.
....


But the original & loudest knocking came after it had been stood for about 40 hours.It was stone cold.

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Fri 08 Mar 2013 @ 01:21 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
Anon
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Knocking.

Hi to all,

And the reason for that early knock would be caused by the amount of time it took the oil to reach the far end of the crankshaft and build up pressure between the crankshaft and the worn shells.
Sorry my old son but it seems you have only one way forward and that is to take that engine out, then fix it or replace it with a good secondhand one.

Doug.

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Fri 08 Mar 2013 @ 10:19 Edit this messageQuote this messagePMQuote this message
Anon
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Diesel engine.

Hi Bluebedouin,

Just spoke to Rae Waters up here in Fife and he said he has a diesel engine 2.5di
transit, only thing wrong with it is a leaking injection pump, maybe you could phone him or send him an e mail.
This might be the way forward for you and get you back onto the road in time for the season.

Doug.

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Sat 09 Mar 2013 @ 10:40 Edit this messageQuote this messagePMQuote this message
bluebedouin
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Update on this knocking.
I've been out twice daily to start the engine hoping it would make the noise.On Sunday I took it out for a "burn up" on the dual carriageway (I had a mate following in case I needed towing back).When I went to start it,it took a few more turns than normal to get it to fire & when it did there was quite a bit of black smoke (but no knocking).This cleared after a while & once I got on the dc everything was sounding fine.I did a few circuits (about 20 minutes)without mishap.
I've since used it as normal around town & there've been no problems.So,I think it was a blocked/part blocked injector which has finally cleared itself.



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Tue 12 Mar 2013 @ 16:42 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
Anon
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Knocking.

Hi bluebedouin,

If that knock has gone it may have been something that went in through the aircleaner and has now be blown out of the exhaust, but that sounded very like a bigend knock on your recordings.
If it starts to knock again you could try slackening back each injector pipe in turn when the knock stops that is the cylinder with the problem.
You could have had a partly blocked oil pickup pipe in the sump, if so it will happen again, and you don't want that doubt hanging over you on every trip you make.

Doug.

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Tue 12 Mar 2013 @ 17:08 Edit this messageQuote this messagePMQuote this message
bluebedouin
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This bloody knocking came back again yesterday about ¼ mile from home.As I went round the corner & pulled up at the house it died down.This is what it sounds like now.Not as bad as it was but definitely there.As I get close to the air intake pipe you can hear a sort of lapping sound,does that mean anything to anyone?Click the pic to watch video.

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Mon 01 Apr 2013 @ 18:32 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
Gethin
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that's sounding like an injector is playing up.

whats the exhaust smoke like at the back?
Mon 01 Apr 2013 @ 19:00 View Gethin   Email Gethin   Edit this messageQuote this messagePMQuote this message
bluebedouin
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I'm in the process of changing one of the injectors now,I noticed it was a bit wet.The exhaust is relatively clear.It's a bit black from cold start but clears pretty quick.

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Mon 01 Apr 2013 @ 20:17 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
bluebedouin
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This is turning into something of an epic!
Having sold the van on the morning of the 1st may it broke down in the afternoon.
To cut a long story short,I bought it back & it's been in the garage ever since.To be fixed on an "as & when they get round to it" basis.They started at the beginning of this week & the problem turned out to be a disintegrated swirl chamber.
The one on the right is the size it should be.

This is the damage to the block & piston.

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Thu 13 Jun 2013 @ 19:02 View bluebedouin   Email bluebedouin   Edit this messageQuote this messagePMQuote this message
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