Carb freezing

[Dave123]

Anybody found a fix for this problem? Other than new carb and warming up before you leave?

I currently have the WEBER 34 ICH fitted, no radiator cowl, a kenlowe fan and the heat shield on the exhaust.. I've read a lot of place the heat shield should be fitted but there's a lot to be desired of how effective it works...

Now it's started to get cold, it's decided to do it and is a nuisance, especially if you're in a rush.. If I'm driving when it happens, I have to slow up on the gears then finally hand brake and pump the accelerator to keep it running, You'd be amazed how many people tell me I have no brake lights :lol:.

[Saffy]

fit a decent zenith - oh you said no sensible answers :lol:

Knit a cosy for it

wrap it in low volt heating trace conductor (not bad idea really !) it used to wrap around pipes and valves to help stop them freezing up.

[landy_bug]

does the engine warm up fully, a rad cover may help keep engine up to temp and keep carb from icing due to cold wind blowing around it making it cool down/ not warm up properly. have had this problem on a mini because too much cold air getting around carb while moving.

i didn't get this problem on my S3 as was fitted with V6 with weber down draught and little use in winter.

hope this may help??

chris

[Devon-Rover]

A rad muff should help keep the engine bay a little warmer to stop it icing up. Sorry i can't help anymore  :(  i have a zenith and it doesn't ice up.

[bogie]

Stick a diesel in?

[bogie]

Find the highest thermostat n stick it in!

[NiteMare]

i'm going to suggest you clean your airfilter out, icing is usually caused by the damp contained in the air that's rushing thru the venturi (the venturi having the highest velocity of air so being the coldest point) settling and cooling on the venturi ...

any water in the airfilter (or link pipe) stands a chance of being sucked out (vapourised) so increasing the risk of icing...

i had this happen years ago on an old volvo, it was caused by water sitting in the airbox, as soon as i drained it out the problem went away

if you can build a snorkel that takes air from around the exhaust manifold you may find this will help alleviate the problem, fords had a little flap in the intake system for taking warm air during colder/damper months to help with this

[Dave123]

Cheers guys, I didn't think of the rad muff so I'll be doing that along with checking out my air filter. I will definitely be changing out the Weber for a Zenith as soon as I can find one?

Tried paddocks, which only sell Weber's and Ebay didn't have any last time I looked so I'll pop over there again in a sec. Does anyone have a suggestion of second hand or cheap units?

[Devon-Rover]

Re: air filter i have a K&N stuck on top of the carb which should make it worse as the air is directly sucked in but still no problems. A bit hit and miss to get a zenith is to buy of ebay. But AFAIK you can still get zeniths new. MY local place brookwells got my new zenith for me a couple of years ago.

[carbore]

Id be following NiteMares advice becuase


A) it sounds really clever
b) it wont cost anything

[TBM]

Is your fan coming on too early?

Most of the Weber carb icing problems are also caused by the standard fan blowing cold air over the carb.

I ran a Weber with a K&N in the Welsh Mountains for four years and never had a problem -most have attributed this to the kenlowe. However I didn't have a heat shield fitted. I also had a higher temp thermostat as well.

Are you sure it's carb icing and not a fuel problem?

Does your bonnet seal well? I fitted some sticky neoprene tape along the wings where the bonnet sits which also kept it nice and warm.

[lightweight-love]

Is this series driven much? as water in the fuel from condensation can cause freezing, and if oil bath filter a clean and oil to right line may help.
Ah the joys of petrols!

[Dave123]

Yeah, the series was sat for a while but about a month ago I've driven it everyday. I'm pretty sure it is Carb freezing because it showing all the symptoms. It's fine when idling cold or hot, it's fine when running cold or hot but it's the bit between being cold and hot when moving seems to be where the engine just won't Idle. You have to idle it with your foot.

In this week though it seems to have developed a problem where it misfires badly enough not to idle when I'm warming it up. When it is warm though you turn off the key, restart and it's fine. I'm just wondering if it's connected?

My tutor advised me to buy new plugs and leads anyway which i can get cheap-ish through the college it's also a 'Job-Card' I have to complete. So I'll be getting new everything including dizzy arm and rotor cap and coil and hope it fixes the misfire then see if it will Idle when sat still or when stopped when cold-warm moving

[NiteMare]

the idle problem when cold can be caused by a mixture of dirt/dust/perishing and damp on the high tension side of your ignition system ...

again an old volvo had this problem first thing in the morning (i lived next to a stream), i used to stick a fan heater under the bonnet for 5 minutes to dry everything out before starting for the first time of the day, once the damp was gone it'd run just fine