One for the technically-minded, perhaps

[Alan Zoff]

Bit of a long-shot this, but I thought I would ask. I'm looking for a small piece (10cm x 10cm would be ample) of a thin (2 or 3mm) flexible material that will withstand the heat at the top of a car engine as it will be bonded to a metal bar between the inlet manifold and the camshaft housing.

Does anyone know of a plastic material that would fit the bill, what it is called, and where I could buy it? I'm trying to make a repair that will avoid buying a new manifold as the bar in question cannot be bought separately. The manifold costs several hundred pounds from Alfa and removal/refitting is a nightmare. I can however lift out and refit the bar without removing anything else.

The material has to be flexible enough for me to be able to push some small metal lugs through holes I will make in it, and must then continue gripping these lugs despite the heat and oil deposits building up over time.

Thanks for reading.

[nomoss]

I am intrigued that you can remove/replace the metal bar but are not considering repairing it or having a new one fabricated, and also at the purpose of a bar between the camshaft housing and the inlet manifold - is it a stabilising bar, or does it serve some other purpose?

I may be able to help, but would need a better description and perhaps a photo.

[Chancer]

Will it be bonded or are these lugs the things that are bgoing to locate it?

Not much heat relatively speaking on the inlet manifold side of an engine and I suspect your problem will more likely be the bonding of dissimilar materials the main one probably being a flexible plastic or rubber.

More info please

[Théière]

Deffo, better picture or drawing, immediate thought was silicone rubber sheet, easy to obtain but something that thin bonded to a bar? 

[Alan Zoff]

OK, here we go.

Certain Alfa, Saabs and Vauxhalls use the same Vauxhall diesel engine. Like some BMWs, swirl of the inlet gases is achieved by butterfly flaps in the manifold which are opened and closed by a solenoid controlled by the ECU. A link from the solenoid drives one of the flaps which is then linked to the other flaps by the bar in question, or rather to discs sitting above the flaps. Each disc has a small round lug, whilst the bar has 4 alloy cups bonded to it which are designed to grip the lugs so that the the bar can be pressed onto the lugs and stay in place whilst allowing the cups to rotate around the lugs. Movement of the driven flap is therefore replicated in the other 3.

Largely because of emission controls that require some of the exhaust gas to be reintroduced to the engine via the EGR, the inside of the inlet manifold gathers soot, oil residues etc which build up on the swirl flaps. They still move but the design of the cups on the link bar appears not to have allowed for the fact that they will not turn as freely after several thousand miles of use as they did when the car was new. The lips of the alloy cups therefore wear out prematurely and the bar simply falls off! This leaves the flaps (other than the one driven directly) in the wrong positions.

My plan to "repair" the cups (the bar itself is fine) is to bond the plastic material to the cups, but with a small hole in each so that I can push the bar back onto the lugs. I am hoping that the plastic will retain the cups on the lugs, doing the job formerly carried out by the worn away alloy.

Hope this makes sense.

I have googled some images here:

https://www.google.co.uk/search?q=swirl+flap+bar&es_sm=93&source=lnms&tbm=isch&sa=X&ei=YAmDU47WIKvA7Ab2r4C4DA&ved=0CAcQ_AUoAjgK&biw=1366&bih=677

Edit: Don't know why but I can't see the full width of the text I just posted

[nomoss]

OK, got it. From your original description I was wondering what purpose a bar would serve connecting the manifold and the camshaft housing[8-)]

Looking at images from your link made it clear, but in the process I noticed the information in the link below, don't know if you've seen it, but it looks a good solution

[url]http://www.vauxhallownersnetwork.co.uk/index.php?threads/how-to-repair-modify-1-9-dth-cdti-swirl-flaps.340436/[/url]

The german eBay link comes up with several options.

Edit: Any possibility of re-routing the entry of the recycled gases downstream of the swirl flaps, or into the parallel passages without the swirl flaps?

[Alan Zoff]

Thanks Nomoss. After posting the Googled images, I was just looking at the same link! That would seem to offer a better solution, although I see also that some guy has got way with using plastic screw caps in a similar way to I intended. The silicone sheet sounds a possibility if it will stick.

Lots of people have apparently looked at ways of rerouting the gases but have run into problems with the ECU or not being able to retain pressure. It's easier with non-turbo charged engines. But getting outside my comfort zone now....

[Alan Zoff]

Sorted!

I've just found this on Ebay:

http://www.ebay.co.uk/itm/4-X-VAUXHALL-SAAB-ALFA-ROMEO-FIAT-SWIRL-FLAP-REPAIR-KIT-1-9-150BHP-Z19DTH-Z19DT-/131093397506?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item1e85c68002

£16 will do me for what looks like a permanent solution.

Thanks for the replies

[nomoss]

It's hard to guess the size of the lugs, but if they have a little ball on top, would it be possible to use something like "Lift-the-dot" or "LOXX" fasteners, fixed to the control bar, to connect them?

[url]https://www.google.fr/search?q=lift+the+dot+fasteners&client=firefox-a&hs=74Y&rls=org.mozilla:en-GB:official&channel=sb&tbm=isch&tbo=u&source=univ&sa=X&ei=aRWDU-GHMbCY0AWYqICwDA&ved=0CCoQsAQ&biw=1360&bih=585[/url]

[url]http://www.nauticexpo.com/prod/schaeffertec-gmbh/metallic-fasteners-boat-covers-upper-part-34155-407451.html[/url]

[Chancer]

I couldnt realy follow your explanation as the text ran off the page.

You probably wont be able to follow this for the same reason

Hence my frequent carriage returns.

Sounds like a press on ball joint that wears and pops off.

Its a bodge but easy to do and has lated well for me.

I use stainless lockwire tightened around the base of the ball

and then looped over the socket and its rod to hold it all together.

I have done gear linkages, wiper linkages and lots of others

in this way

[Alan Zoff]

I don't know why my text has started running off the page but, as mentioned, I think I have found a solution to the bar problem.

The main problem is the small size of the "ball and socket joint" and the impossible location of the discs with the lugs (balls). All the work has to be done on the bar cups - no prospect at all of working on the lugs.

But cutting off the existing cups and replacing with the brass ones from the Ebay site will mean I can repair it and hopefully forget about it for the rest of the time I will have the car. As with any diesel turbo, just need to make sure it gets a good run every few days to keep the airways reasonably clear, and occasional removal and cleaning of the EGR.. Short journeys - particularly in winter - are the killer, in terms of soot build-up.

[nomoss]

[quote user="Chancer"]

I couldnt realy follow your explanation as the text ran off the page.

You probably wont be able to follow this for the same reason

Hence my frequent carriage returns.

Sounds like a press on ball joint that wears and pops off.

Its a bodge but easy to do and has lated well for me.

I use stainless lockwire tightened around the base of the ball

and then looped over the socket and its rod to hold it all together.

I have done gear linkages, wiper linkages and lots of others

in this way

[/quote]

I'll borrow that idea, if I can remember it[:(]  I'll make sure there is some suitable wire in my toolbox, or put some with the coathanger and gaffer tape.

I think the lugs are too inaccessible to use it on the Alfa, tho'

[Alan Zoff]

Yes, I have done that Chancer on a couple of floppy gear linkages. (We were stuck at Birmingham airport once in a VW Golf with no transmission but fortunately I cadged some wire which held it together until we got home.)

But no chance of anything similar for this problem. I just need the brass cups I have ordered to make a nice push-on fit once I have screwed them to the bar.