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Calling for Doctor diesel

Posted: 18 Sep 2010
by Bx Bandit
Got a mild diesel clatter or it even sounds a bit tappety between about 1500 - 2500 rpm. Pretty sure it's nothing to do with tappets.
Not the beginnings of turbo bearing failure is it?

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Philhod
:) Sorry you have a clatter Bandit. Hope it soon gets better :oops:

Usually when the turbo is beginning to fail you get a chirping/ whistle, (high pitched) which generally lowers as it deteriorates. Provided it is not short of oil it could be 12 months between first and last.
If that Turbo you gave me was any good, it's only in bitz, I could re assemble it for you should you need it back. 8)

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Bx Bandit
It has been sounding like an ambulance is chasing me, but the TGD went on like that for years, but you've reminded me that the tone does get deeper with time!

When I had the Hurricane in '97, it developed a proper fucked turbo, like a grating sound in boost. What I have now sounds like it could be the beginings of that.

I just can't think of what else it could be.

Thanks for the offer of returning the turbo Phil. You bring me on to part two of a related dilemma but you've no need to return the KKK unless Vanny wants it back at is was his initially.

If it turbo, I assume it'll carry on for a bit anyway? Even though it'll sound like a tractor having an epileptic fit?

But, I'll need a turbo for the 2.1. Why not use the original 2.1 turbo I hear you say!!!

Well, mostly as it wont fit without some buggeration and even then it'll force me into a front mount i/c which (possibly) I'm keen to avoid!

The turbo on the 2.1 was a GT15. Looking on Garrets website the GT15s are more suitable for 1.0L to 1.6ltr engines (although petrol ones I assume?) I've not done any of the flow calcs yet but based on the max rpm a petrol vs diesel engine will reach, then (2.1 x 4000)/6000 = 1.4, which means the GT15 is about right .Oh bugger, that's blown my theory, I had thought the GT15 was too small for the 2.1......

With that setup it's all down low and rather have slightly longer legs in the turbo department. A GT17 seems about right possibly, based on what other manufacturers have used for smaller (than 2.1) engines but I can't find a compressor map or any info. There don't seem to be any compressor maps anywhere for manufacturers vehicle turbos :evil:

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Bx Bandit
arse bangers, the GT15 turbo off the Xantia has more play than a playful puppy at play time.

Anyone overhauled a turbo????

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Philhod
You need a press for the spindle and quite often they are peened in as well after fitting.
Unless your detail fitting skills are up to it I would suggest stripping a scrapper fitst.


What about the one on the Picasso? It meets a fair range of mapping from 90 to 138bhp
(ok an I/C gets added) but it meets the blow requirements. It also has asymmetric vanes.
This gives push from 1800 revs right up to 4000. Albeit a bit short on torque low down

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Bx Bandit
I have press, but not done one. Have two to practice on. Just realised I put the 'overhauled' post in as there was a GT17 going on ebay for next to nothing but in need of a refurb. Ideal I thought. Fuck - got side tracked and forgot to bid :evil: It's all over now

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Philhod
Start by removing any delivery pipes etc and draining out any residual oil. Then remove the compressor (air end) Once thats off you will have to examine how the shaft is secured, there are lots of methods, and remove any mechanical locks in place. (peening is just one example) then it should press out. This could take some pressing as some Garrets were coated in blue loctite :x Garret used to provide a new shaft with the turbine (exh end) already fitted, along with a bearing kit.

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Bx Bandit
There are kits of varying and indeed probably dubious quality on eminge, some up around the £100 mark :x Is it the bushes or shaft that wear? I would of thought bushes but why supply the shaft?!

Re: Calling for Doctor diesel

Posted: 18 Sep 2010
by Philhod
Because on the earlier ones you generally had to wreck the thing to strip it (loctite)!!!! :lol: :lol:

I've even torn the metal and left that fucking stuff in place :x

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by docchevron132
I've seen some very worn shafts, albeit usually from engines where the owners would arsehole to a stop from speed then switch the engine off.
I often wondered about fitting an electric oil pump to keep feed to the turbo until things had cooled down a tad / stopped spinning.
Then I thought fuck it and went for more beer.

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by Philhod
:shock: You mean you are going to pump beer in to cool things off [chin] [no]


The central chambers on Garett's and KKK's are big enough to cope provided that you stop normally; ie; pull up at parking speed, then just switch off. :D

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by docchevron132
Depends how hard you drive I guess.

I've heard tell before that the lack of oil flow with the motor switched off can mean the remaining oil boils it's nuts off and does little to lube the turbo whilst it arseholes round at a fair few thousand RPM?

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by mat_the_cat
Plus, if the turbo is really that hot, even if it has stopped spinning the oil sat there can turn to carbon which doesn't lubricate quite as well...
I think the BX manual mentions to leave it idling for a while if you've been caning it, although perhaps not in those very words. I haven't seen that mentioned for a modern TD, so it may be that the problem is less/not there with modern oils?

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by Philhod
The only real changes are the central chamber is a little more offset and slightly bigger.
It should stop spinning within 20 secs too and carbon powder lubricates quite well actually Mat. Not that it would ever get to that stage as the casing cools quite quickly. 8)

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by Bx Bandit
Well it's getting worse, not noticeable on cold though. It could also be the CRB as I'm sure the noise follows the engine revs as opposed to the noise lagging behind the rpm...........if that makes sense.

Re: Calling for Doctor diesel

Posted: 22 Sep 2010
by Philhod
:? :? What's the Criminal Records Bureau got to do with it? [no] [coat]

Re: Calling for Doctor diesel

Posted: 23 Sep 2010
by mat_the_cat
Philhod wrote:carbon powder lubricates quite well actually
Graphite would, yes. But heating oil till it carbonised wouldn't form graphite...

Whether the turbo would be hot enough to carbonise oil sat in there after turning off I don't know for sure. But I'll leave it running for a short while just because it gives me that warm glow of satisfaction looking after my turbo. :)

Re: Calling for Doctor diesel

Posted: 23 Sep 2010
by docchevron132
Having trashed 3 turbo's in as many thousand miles I'm more inclined to drive with some mechanical sympathy these days.

Re: Calling for Doctor diesel

Posted: 23 Sep 2010
by Philhod
it gives me that warm glow of satisfaction looking after my turbo.
....knob!!
:lol:

It doesn't even boil.... unless you are running verrrrry retarded.

Re: Calling for Doctor diesel

Posted: 23 Sep 2010
by mat_the_cat
Who are you calling retarded? :lol: