1.6 Hdi / DV4 / DV6 turbo feed modification.

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Bob L'eponge
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Bob L'eponge » 14 Dec 2013, 07:19

Peter.N. wrote:I know there are a lot of 1.6Hdi's out there so that's going to affect the problem numbers but have a look on Honest John's forum under 'Ford Focus TDCI turbo failure' or similar, the last time I looked there were around 250 posts, I have never seen a topic with so much interest. There don't seem to be an abnormal amount of posts on any other engine.
Just do a quick search for 'BMW N47 engine problems' to see an even hotter topic! Even 'Watchdog' got involved with this one. :wink:

Audis are even worse, with Warranty Direct reporting that the only make to suffer more engine failures than Audi are MG, who don't even exist any more.

By the way Ford, a big user of PSA Hdi motors, still came 7th in the above report, only slightly behind Fiat. Volvo, another big user of PSA Hdi motors was 4th...

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Lighty
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Lighty » 14 Dec 2013, 08:01

The exhaust filter, or DPF needs to be removed to get the oil feed pipe off, the filter is located inside the lower banjo bolt.
Removing the dpf is quite a big job, especially on your 1st attempt, but there is nothing impossible, it's just nuts & bolts.
We remove the radiator on most cars for easier access.
I would strongly recommend removing the filter on ALL 1.6 hdi engines. We have had some well looked after vehicles with turbo failure, so don't think yours will be ok.

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Lighty
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Lighty » 14 Dec 2013, 08:12

One type of filter, smaller than your little finger nail

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Banjo bolt


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Removed

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Dpf& turbo removed

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Dpf , note the soot leakage, indicating a restriction

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Peter.N.
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Peter.N. » 14 Dec 2013, 11:41

I still don't understand why 30 micron particles from the main filter can cause this problem. Yes you can get lots of carbon granules in the sump but I fail to see how they get into the turbo :? Can someone explain?

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Hell Razor5543 » 14 Dec 2013, 11:54

Well, as the turbo is spinning at an extremely high level of RPMs, it (obviously) needs to be lubricated. The bearings need to be able to handle the stresses put on them by this high speed. If the oil is up to spec (and clean) then there are no problems. However, if there is a problem (wrong/dirty oil) then either the bearings don't get the necessary level of lubrication, and seize, or if crud gets into them the bearings run un-evenly (but not for long) and let go.

As the oil is circulating throughout the engine, it makes sense that, while particles will eventually get down into the sump, they could pass through the turbo on their route. The turbo uses the same oil, and is part of the normal oil pathways.

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Mandrake
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Mandrake » 14 Dec 2013, 12:07

I think Peters point is that the oil feed to the turbo is presumably fed directly from the main filter, mostly through an external pipe - it's not as if its being collected from the rocker cover and then being fed to the turbo :lol: Somehow the carbon has to pass through the main filter to reach the turbo feed pipe.

I think the answer to the question has to be that either the main oil filter is getting clogged forcing the bypass valve in the filter to open (letting all the crud through) or that the main filter is of poor quality - a number of previously "well regarded" brand name filters have recently been shown to be sub-standard, including poorly designed bypass valves that leak or open too easily.

I read a really thorough test and analysis of oil filter performance recently and the results were quite shocking, frankly. Some oil filters are to put it bluntly, junk. If I can find the article again I'll post the link. A filter is a filter is a filter is unfortunately not true anymore thanks to cost cutting during manufacture.

Poor oil filter quality and the ridiculously long service intervals on this engine and I can easily see the turbo filter being blocked with crud that has got through the bypass in the main filter.

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Peter.N. » 14 Dec 2013, 13:15

I'm convinced that infrequent oil changes are the source of the trouble but didn't know about the problem with poor quality filters, presumably if the oil was changed more frequently the filter problem would not be so critical. I have done 100's of thousands of miles in PSA turbo diesels, starting with the CX then BX, XM and now C5 and have never had a hint of turbo failure but have always changed my oil at 5k until the Hdi which I leave a bit longer, but have used the cheapest obtainable in spec oil. The smaller sump capacity of the 1.6 must play a part demanding even more frequent changes. Your point about the oil filter clogging and oil bypassing it Simon had not occurred to me but it could well be part of the problem.

Peter

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by myglaren » 14 Dec 2013, 14:39

Mandrake wrote: I read a really thorough test and analysis of oil filter performance recently and the results were quite shocking, frankly. Some oil filters are to put it bluntly, junk. If I can find the article again I'll post the link. A filter is a filter is a filter is unfortunately not true anymore thanks to cost cutting during manufacture.
I would be most interested in that if you can find it Simon. Many others too I'm sure.

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Lighty
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Lighty » 14 Dec 2013, 16:46

The dispatch and expert vans with this engine, have a larger sump capacity, and do not seem to suffer anywhere as much from turbo failure.
Personally I would change the oil every 5000 miles, and this would help to cut down the risk .

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demag
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by demag » 19 Dec 2013, 17:06

On my engine which is pre fap, is it possible to get the banjo filter out without dropping the exhaust? If so I can probably do it myself. But if not I don't fancy dropping an exhaust in this freezing weather so will pop it to my local garage.

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Bob L'eponge » 19 Dec 2013, 17:42

For comparisons with Lighty's photos, here is the new banjo bolt with the filter pulled out so you can see it. Not only does the new filter have a larger surface area and a larger 'capacity' before it would be blocked by any particles, it also seems to have a finer mesh.

Image

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Peter.N. » 19 Dec 2013, 18:44

Looking at that filter I can understand why it would clog up if the oil gets sludgy as I'm sure it does with the current oil change intervals, the oil pump can push it through the main filter but probably not that one. I don't think the XUDs had that filter and turbo failure is very rare on those but they had more frequent oil changes.

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Xantidote » 19 Dec 2013, 21:31

If the sump capacity is a bit on the lean side, then keeping the oil level topped up to MAX might have some benefit

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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by uncle buck » 22 Dec 2013, 15:32

Looks to be the same sort of filter that was fitted in the oil feed pipe on the XUDs....the filters were fitted from the factory but they were removed at the cars first service.


Picture from the Citroen ZX Haynes Manual

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Peter.N.
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Re: 1.6 Hdi / DV4 / DV6 turbo feed modification.

Post by Peter.N. » 22 Dec 2013, 15:40

..interesting