fbekholden.com

So driving from Albury to Melbourne this week in the early hours of a very cold day sitting about 60 mph I was finding my carbies were icing up. To the point I would lose power up hills, and the grey would continue missing and running really rough.

Pulled over several times and the throats were white with ice just above the manifold.

Let it idle for 5 minutes you could see them thaw out a bit then kept going for another while till it happened again. Repeat.

Twin strombergs on a speco manifold and extractors.

Thinking the GMH people had something like this in mind with the original exhaust valve set up and the two manifolds connected as one big heat sink. Had the EK In Vic and Tas along time with a single carb set up and extractors and never had the issue.

On the morning the temp gauge (instead of the dash light) struggled to hit 70degrees.

Any one else experienced this? And any sharing for the forum on how to manage this with twins/triples and extractors?

May be unrelated but I also am wondering whether my jetting size could be a factor. (On the fuel rich side based on my mileage calcs the past 3 weeks.


Blackdog.

John,

I'm guessing the ambient temp will have been near freezing and the relative humidity close to 100%, so I'm not surprised that your carburettors iced up. In the '80s my bro and I drove down to the snow in his recently purchased '65 Merc 220S and we had the same problem near dawn at about Michelago. The exhaust manifold heat riser valves had long since stuck shut.

If it's any consolation, the B-36 (that enormous six-piston-engine, four-turbojet bomber) was notorious for icing carburettors up.

It's why the X2s had a water-heated inlet manifold.

If you know someone who's a wizard at welding aluminium, buy a length of 16 mm dia aluminium pipe, get it welded to the outside of your inlet manifold, and plumb it into your car's cooling system in parallel with the heater.

Rob

Just as a matter of interest, are you still using the black spacers between the carbs and the manifold?

ardiesse wrote: Tue Jun 28, 2022 8:53 pm If you know someone who's a wizard at welding aluminium, buy a length of 16 mm dia aluminium pipe, get it welded to the outside of your inlet manifold, and plumb it into your car's cooling system in parallel with the heater.

... or the temporary, redneck version: take your heater hose (either one) and extend it a little longer. Loop it around the carbs where they ice, and cable tie it in place so it does not foul the accelerator linkage. Remove in summer.

Cheers,
Harv

Thanks Gents

I guess living out of the cold climates means you don’t get to deal with this often or at all.

Brett I’ll check but I’m pretty sure they are still on.

Rob and Harv, ta got it. Water jacket solution to be imagined and made. (From proper welded to hill billy moonshine plumbing)

Thanks!!

Blackdog

Well you could do all the plumbing or you could try just taking off the insulators for winter. Manifold might get warm emough just from the engine and sitting above the exhaust, but with the insulators there the carb bases are not getting much from it.