10 replies to this topic

[JakeJakeJake]

I was just wondering what the tube indicated is? Even if it does not lead anywhere should it now have a plug on it?
Is it where you can put the crank case breather? Also should the fuel pipe really loop around the air filter like that?

And finally if that is not too many questions , what are your views on manifold heat wrap?

Attached Files

•  carb_question.jpg   367.74K   42 downloads

[dwealds]

Im not sure on the carb questions as i have an injected Mini but on the heat wrap side of things I have heard it isnt much good and can be dangerous.

Two things that I can suggest instead and they are a ceramic paint which I have put on my manifold and it has reduced the heat by a bit. The other thing is there was an article in this months Mini Mag or Mini World (sorry can't remember which) about a kevlar heat wrap that looks really good and seems to give great heat reductions under the bonnet, they also do a silencer wrap to go with it as well, it can all be bought as a kit.

Hope this helps

Dan

[JakeJakeJake]

Thanks was in miniworld, kevlar wrap is expensive how much would be needed for a manifold? standard wrap can cope with 1000 or ºC is that not enough?

[adam_93rio]

im pretty sure that pipe goes to crank case breather like you said,
but your fuel line is not standard it should be a different type of pipe (bit like a brake line) and goes under the carb not over

Edited by adam_93rio, 02 November 2009 - 07:23 PM.

[Dan]

The port on the carb is for the breather system. The best thing to do is to hook it up to the crankcase ventilation system and use it to suck the crud out of your engine but if you don't want to it must be plugged. If it's left open to atmosphere it will lean the mixture off dangerously.

The fuel line is better up there than hanging down draped over the exhaust. That section should be under the carb and made of solid metal pipe but if it's all been replaced with hose you do need to keep it away from the manifold. It's not going to be a problem for the pump to push the fuel a couple of inches higher like that. It could lead to airlocks in the line though.

My personal view on heatwrap is that it's terrible stuff. The Mini engine bay is well ventilated, heatwrap just moves the heat further back along the system. I've seen it cause exhaust bobbins to melt and it makes the floor around the tunnel very hot to the touch.

[dwealds]

Im not sure on how much is needed as I didn't want to put standard wrap on my manifold but I would imagine quite a few feet with a 50% overlap.

On the heat resistance i would be seriously worried if your manifold got anywhere near 1000 degrees C so it will be absolutely fine. The only thing I would say if you're going to put standard wrap on your manifold is make sure that you cover every single mm of it, otherwise it can in extreme circumstances cause a hot spot which can set fire to the heat wrap or oil if you get a leak. As I said this is what I have heard, not experienced it myself.

Dan

[JakeJakeJake]

If it sucks crud out the engine, where does it go? Is that better than a breather filter?

As for heat wrap I think I will leave stick without it, thanks for all your help

[dklawson]

The crud is burnt by your engine. As mentioned above, the carb port is basically the connection point for the PCV valve/system.

I have wrap on my Mini's header. It does make the under-bonnet temperature lower. However, as mentioned above it does have a mixed reputation. The most common complaints are: 1) It is blamed for collecting moisture when the car is only driven short distances (leading to rust issues), and 2) overheated spots in/on the pipes resulting in damage.

My manifold is wrapped because it was old and pitted/pin-holed so I had nothing to loose. I consider my header an experiment to determine if I should have a new/replacement header ceramic coated. Since I do see lower under-bonnet temperatures (and the floor isn't unreasonably hot, and I've never seen damage to the bobbins as mentioned above) I will consider ceramic coating any future exhaust components I install.

[lrostoke]

Just one thing are we sure thats the port for the engine breather, looks more like its above the fuel inlet which would make it the overflow/vent pipe.
Engine breathers normally more towards the manifold

Edited by lrostoke, 02 November 2009 - 08:37 PM.

[Asphalt]

That tube actually is the float chamber's vent.
The breather connection is the larger tube next to it (not visible in the pic).

Usualy it conects to a smal tube going 'round the clutch cover to lead fuel away from the exhaust in case of overflow. I'd at least put on a hose pointing down (and leading away from the exhaust manifold) to prevent dirt from geting in (well, that's what I did as I lost the tube).



[4: fuel in]
5: float vent
6: breather connection
[7: mixture adjustment screw]

Cheers,
Jan

[edit] Beaten to it...

Edited by Asphalt, 02 November 2009 - 08:36 PM.

[JakeJakeJake]

I see now thanks everyone, so just put a bit of pipe on it facing down and away from manifold to keep anything nasty out