mishu 0 Posted August 11, 2006 (edited) I noticed that the exhaust section communicates with the intake manifold. I assume this is to make the engine warm up faster when it's cold, by feeding it hot exhaust fumes (hope I'm right). My question is, has anyone removed the link and noticed any considerable change? (Especially in winter I'd imagine) I was thinking of simplifying the air flow and just mounting an air filter before the carb (That would also get rid of the huge connection between the air filter/carburator -- what is that oval..ish black plastic thing for, anyway-- just a tube between them?) This is what the engine bay looks like now (I'm taking it apart to clean and replace parts as needed next week): Engine is a 1990 TU1-H1A (so 1.1), btw. Also, I'd also like to replace all the tubes with braided ones once the engine bay is all shiney, because I really like the look they give (saw a 205 with them on this forum not long ago -- looked great). So any advice regarding that would also be appreciated. Edited August 11, 2006 by mishu Share this post Link to post Share on other sites
Tony_205 1 Posted August 11, 2006 Hi mate, you are right, as the intake manifold is fed both hot AND cold air.. Share this post Link to post Share on other sites
brianthemagical 1 Posted August 13, 2006 it will work at least ok. my mates ax (1.4) hasn't got a filter and that runs fine, i also saw a hillclimb car without a filter and his ran fine. the pipe work is there to suck in hot gasses from around the exhaust shroud when the engine is cold, there should be a small flap valve in the join to control it. the idea is to get the engine as warm as possible and consequently the engine more efficient quicker. removing it may just mean you have to have the choke out longer or something like that. Share this post Link to post Share on other sites
Guest cknotty Posted August 13, 2006 The bolts holding the shroud and the surrounding metal for the hot air feed rusts through eventually, and it'll fall off. Happened to my car on a rally, and it got wedged in the radiator No leaks luckily, and it's still in the car, albeit with a few damaged fins Haven't noticed any real problems in cold weather yet. Taking the standard air ducting off frees up a lot of space in TU engined 205s, so it can be handy. I'd suggest putting in some ducting in yourself, so the carb can get some colder air. my mates ax (1.4) hasn't got a filter and that runs fine Wouldn't recommend running a car without a filter, as you don't know what rubbish could get sucked into the cylinders... Chris Share this post Link to post Share on other sites
mishu 0 Posted August 13, 2006 I'd suggest putting in some ducting in yourself, so the carb can get some colder air. Is there a recommended place to put the air filter? I haven't thought that far ahead yet Share this post Link to post Share on other sites
Sandy 191 Posted August 13, 2006 You have to be careful, they do suffer carb icing in cold weather without the hot air feed. Share this post Link to post Share on other sites
Guest cknotty Posted August 13, 2006 (edited) If you get something like a K&N filter (induction kit, not replacement filter element) for it, it attaches directly to the top of the carb, hence why you need a cold air feed. Having said that, when I had one on mine I didn't notice any real problems. Makes a nice noise too! [edit]Just noticed, I've become a driver now, woohoo! [/edit] Edited August 13, 2006 by cknotty Share this post Link to post Share on other sites
mishu 0 Posted August 13, 2006 (edited) You have to be careful, they do suffer carb icing in cold weather without the hot air feed. Can you please elaborate on that? What can be done to prevent it? Edited: cknotty, Congratulations! Edited August 13, 2006 by mishu Share this post Link to post Share on other sites
Sandy 191 Posted August 13, 2006 Carb icing is when the air passing through the venturi causes frost to form which strangles the carb, it also worsens the fuel atomisation, compounding the problem. Restore some hot air feed in cold weather. Share this post Link to post Share on other sites
Guest cknotty Posted August 13, 2006 So, what are the symptoms of carb icing Sandy? Just curious as although I have used the 205 this last winter, if it's been a relatively mild one then I may not have noticed this happening. If the venturis are being strangled, and the air flow impaired then I guess it would be things like poor idling, stalling and kangarooing perhaps? Share this post Link to post Share on other sites
Jrod 7 Posted August 13, 2006 When I had carb icing on my bike it was fine if you kept the power down but when you backed off it was like you were out of fuel, also cut out at low revs and wouldn't start easily again. Fingers crossed won't get it with the car but knowing my luck. Share this post Link to post Share on other sites
Sandy 191 Posted August 14, 2006 It usually happens when cruising at speed or continuous wide open throttle, as Jrod says, you have to keep the throttle wide open to keep the engine going. Share this post Link to post Share on other sites
Guest cknotty Posted August 14, 2006 Cheers guys: haven't noticed any problems yet, but it'll be something to bear in mind if (when more likely) it starts happening! Jrod, that's a very orange engine, is it supposed to be that colour? Can't tell from the piccy! Oh, and your dipstick is the opposite side of the manifold to mine: what's up with that, did they put them whatever side they felt like at the time? Chris Share this post Link to post Share on other sites
Jrod 7 Posted August 14, 2006 It's actually red but I'll let you off. Was on a XS i broke for spares so swapped it over as it looked nice. All 3 of mine have had the dipstick on the same side as mine! Share this post Link to post Share on other sites
Guest cknotty Posted August 14, 2006 Hehe, it looked about as orange as my hair... well almost! As for the dipstick thing, I've figured it out now: just be being a muppet that's all The original engine blew up on my XS, so it was replaced by one from a 106 Share this post Link to post Share on other sites
christopher 5 1 Cars Posted August 14, 2006 Can you please elaborate on that? What can be done to prevent it? Edited: cknotty, Congratulations! Carb icing occurs when there is humid air, and the temperature drop in the venturi causes the water vapour to freeze. The ice will form on the surfaces of the carburetor throat, further restricting it. This may increase the venturi effect initially, but eventually restricts airflow, perhaps even causing a complete blockage of the carburetor. Icing may also cause jamming of the mechanical parts of the carburetor, such as the throttle butterfly valve. I have disconnected my warm air feed. Yours works on a vacum. The vacum hose cause the flap to close the warm air feed when the engine is warm enough. Ín Denmark it is even colder in the winter so we have this effect. Also the water vapour can freeze in the the fuel. However all these effects are removed my adding a special kind of alcohol in the fuel that absorbs the water and makes it flammable in a sense... Share this post Link to post Share on other sites
mishu 0 Posted August 14, 2006 The gasoline we get here does have water vapour (quite a lot of it). I guess I'll just go ahead and put an air filter, but keep the warm air feed in storage, just in case. Thanks for all your replies! Share this post Link to post Share on other sites
