hi can this be stuck as a sticky info on swirl flaps and actuators.ta
http://www.ms-motor-service.com/ximages/pg_si_0093_en_web.pdf
http://www.ms-motor-service.com/ximages/pg_si_0093_en_web.pdf
Technical jtd 16v swirl flaps
- Thread starter sussexa
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Technical jtd 16v swirl flaps
john55
Established member
Swirl flaps are very dangerous things. Just ask a BMW Diesel owner. They have a habit of breaking off, going into the engine and destroying it. Bent valves, scored bores, cracked pistons. A small piece of metal can do a lot of damage inside a diesel engine.
The best advice (and BMW forum opinion) is to remove them. I have on my 320D and it makes 0 difference to the running of the engine / economy since I removed them. It also means the engine will go on for ever, instead of destroying itself in a cloud of smoke at some very inconvenient moment and costing £4K+ to put back together.
Pierburg also make the BMW inlet manifolds / swirl flaps as well as the these fiat/ vauxhall ones, and on some others too. Most makes of 16V diesels with swirl flaps have had issues of failure. I know Vauxhall certainly has.
Also, soon even petrol engines will be fitted with swirl flaps, to meet new euro requirements although I suspect they will not take such a beating as there is no turbo or EGR gunge in a petrol engine manifold.
The best advice (and BMW forum opinion) is to remove them. I have on my 320D and it makes 0 difference to the running of the engine / economy since I removed them. It also means the engine will go on for ever, instead of destroying itself in a cloud of smoke at some very inconvenient moment and costing £4K+ to put back together.
Pierburg also make the BMW inlet manifolds / swirl flaps as well as the these fiat/ vauxhall ones, and on some others too. Most makes of 16V diesels with swirl flaps have had issues of failure. I know Vauxhall certainly has.
Also, soon even petrol engines will be fitted with swirl flaps, to meet new euro requirements although I suspect they will not take such a beating as there is no turbo or EGR gunge in a petrol engine manifold.
someone i work withs vectra has the swirl flaps on the 1.9cdti 150 and they have stuck/broke.. he fixed them with a washe i believe and therew working okay
whats the purpose of a swirl flap?
Something to do with improving fuel mixing by introducing greater turbulence in the air being drawn into the combustion chamber I think. But John55 is right - avoid them like the plague! Do a search on Google - there are a lot of very unahppy people whose engines have been seriously knackered by disintegrating swirl flaps!
Although not electronically controlled, there was a similar system in the old 1985 Croma CHT (Controlled High Turbulence)
Dave.
Dave.
john55
Established member
Basically it turns your 16V engine into a 12V engine at low RPM. Blocks 4 inlet ports which makes the air mix better with the fuel as it is injected. Air enters the chamber at higher speed (through only one valve) and swirls inside the cylinder, aiding efficient combustion at low load / low speed conditions. When more power is required, the swirl flaps open and it becomes a 16 valve engine.
The valves are small, delicate and under a lot of stress in a diesel. See my other post about failures.
do the t-jet petrol engines have them or just derv?
john55
Established member
I don't think any production petrol engine needs them yet to meet euro emissions standards. I think they are still in development by manufacturers. They will not actually fit them to cars unless forced to by new Euro standards, because it all adds cost. I could be wrong though.
if i have they are coming off
the starjet engine has these flaps, i dont know if the T jet is a starjet or not, but i assume it is. gimme a min, i'll see if i can dig up some pictures
starjet is non turbo. Tjet is turbo (but you know that already arc!)
i hope they havent.
anyways, if they had would it not improve slow speed performance by removing them?
i hope they havent.
anyways, if they had would it not improve slow speed performance by removing them?
yeah, just wondering if thats focusing on the trim levels or base spec. There is no reason why the starjet gear (cam variator and variable inlet stuff) can't be present on the Tjet engine - and the 'tjet' just means it has a turbo as well.
found these. Its from the GP, but it shows the swirl flaps.
found these. Its from the GP, but it shows the swirl flaps.
here some pics of bits you wouldn't expect to see for a few years yet.
photos of star jets bits
plastic starjet throttle body even the butterfly is plastic
soon they be making plastic engines :bang:
oh boy
i don't know what the systems are like on the BMW, but glancing at the GM solution shown in the PDF - they're a bit clunky and over the top for what they need, and FIATs solution is better and much less prone to breaking. I would be suprised to hear of a failure where debris enters the cylinders
john55
Established member
Well, they have made into petrol engines already.
The Fiat Petrol engine ones shown in the photo would never work in a Diesel (as in the PDF and the BMW ones that fail) because of the EGR soot would just jam them open very quickly. A rotating valve has to be used in diesels because they are sort of self cleaning as they rotate.
ahh i see, never thought of it like that. That explains why the ones on the diesel engines look so different.
I've just had a horrible thought. Does the Abarth 2.4 engine have these flaps? 
This item:
http://www.fiat.com.sg/defaultf5b3.html?MenuId=69
talks about a variable geometry intake manifold. And there is some sort of device on the end of the manifold opposite to the throttle valve...
This item:http://www.fiat.com.sg/defaultf5b3.html?MenuId=69
talks about a variable geometry intake manifold. And there is some sort of device on the end of the manifold opposite to the throttle valve...
I've just had a horrible thought. Does the Abarth 2.4 engine have these flaps?
http://www.fiat.com.sg/defaultf5b3.html?MenuId=69
talks about a variable geometry intake manifold. And there is some sort of device on the end of the manifold opposite to the throttle valve...
no, the abarth has got the device fitted to shorten the intake on high (4k+) rpms (to go with the camshaft variator??) , you can check it by revving the engine above 4k rpm - the black actuator will move, it's defo not the swirl flaps
also, i think it is worth mentioning that the swirl flaps are not horrible things - and aren't likely to fail in the way they do on a diesel engine
