Ghia Icing Issue- Air Cleaner?

[FL-Frank]

64 Ghia fitted with rebuilt engine 2500 miles ago. '62 case built to 1320 cc with Solex 30Pict1 carb. 6v. Electricals. Carb tuned, timing set at 10 btdc. Stock muffler. Dynoed at 46 HP. The engine runs smooth and pulls strong, however, carb body and manifold to carb tube sweaty and cold to touch. 85 degrees, 75% humidity. Left side heat riser tube HOT to touch, right side heat riser tube warm to touch.

Before I start removing the muffler and/or manifold to inspect for carbon blockage, I'm wondering if my air cleaner is correct and complete for my application?

VW Mann Filter 281129813A. (Picture attached).

It has a preheat hose connected and running from the muffler to the snorkle, and the snorkle flapper moves freely. Is my AC set up correct and complete, or is it missing something?

Please share your pictures of correct and complete 64 Ghia air cleaners.

Thanks!

[Redlabel6]

Sounds like the fuel being vaporized is just lowering the temp of the carb and manifold below the dew point.
You wouldn't notice it if the humidity was lower.
d
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1957 Oval Window Beetle
1973 Karmann Ghia Coupe
https://www.thesamba.com/vw/forum/viewtopic.php?t=666792&highlight=73+coupe

[williamM]

You can force the hot air to the carb by setting the flapper over to "Winter" running- Just close it till the spring wire snaps over the snorkel and stays "hot air all ways" position-

But- untill you have a performance problem- I wouldn't worry- and agree the fact that one side of the heat riser is HOT and the other isn't, proves it's working-
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some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[FL-Frank]

Thanks guys. Its always hot and humid where I live 😊

Does my AC set up look complete and correct to you? How would I convert the flap over to winter setting as suggested? I dont see where or how the wieghted axle the that the flapper is attached to can be looked to hold the flap closed???

Also, I just noticed a large crack in the horizontal manifold tube starting at the base of the vertical tube to the carb, and running approximately 3" in length. Picture attached. Wondering if this could be contributing to the icing issue?

[williamM]

This actually belongs by the AC pictures-



If your AC is equipped (I thought they all were) the wire loop opposite the weight should have a notch that it can be sprung into to hold the valve closed.

Got it right the first time- should have re-read my post-- Naw- would have just got confused-- Candy- get poppa a beer- Good dog.
_________________
some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[OLD VW NUT]

That crack is the casting that covers the intake runners to heat the air. Not uncommon to have them crack. Not a problem unless it fall off - then you have less contact with the intake runners. You say your muffler is stock. As in NOS? Or aftermarket stock? The original stock muffler had some plumbing inside it that helped draw exhaust gases through the preheat tube. Many so-called stock (aftermarket stuff/junk) mufflers have no interior plumbing that the preheat tube needs to operate properly.

Drawing engine heat into the air filter isn't enough to prevent icing. I'm very familiar with this issue since I've lived in the NW all my life. When the air temps are 50* and under and humidity at the same number or higher icing can be a real problem. A working preheat tube/muffler combination is the best solution.

Here's a 'proper' 40hp muffler with plumbing with the right side showing the scavenging pipe. Gases flow from left to right in a working setup:

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71 Ghia Coupe - stock body - no rust! Powered by a 2110 W/Dual HPMX 44's - Rancho Pro Street Transaxle - A/C by Gilmore

Other car - 2013 VW Golf TDI

[FL-Frank]

I wired the ac flapper closed, and went for a quick test drive. 88 degrees, 65% humidity. Engine performance was noiticably sluggish. No signs of condensation on carb or manifold when I returned to the garage. I then freed up the flapper, and took it for another test drive. Noticeable improvement in performance, and upon return to the garage, no evidence of icing on the carb or manifold Possibly the higher outside temp and lower humidity than this mornings test conditions eliminated or at least reduced the icing symptoms noted this morning?

[OLD VW NUT]

The warmer air gets the less dense it is. That lowers compression which lowers the power output of the motor. I posted a pic above your last post. Does your stock muffler look similar? You may only need to remove the intake manifold and clean the passage of the heat riser for it to work correctly.
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71 Ghia Coupe - stock body - no rust! Powered by a 2110 W/Dual HPMX 44's - Rancho Pro Street Transaxle - A/C by Gilmore

Other car - 2013 VW Golf TDI

[FL-Frank]

[williamM]

The fact that you have one running cooler than the other precludes any blockage- that extra heat loss is imparted to your manifold for anti icing. And yes making your engine run all it's intake thru the small preheat probably did make the performance drop- the fact that the later air cleaners had full sized preheat tubes makes me thing the engineers had a bit of a meeting and came up with better warm air stuff.

Again I would say- if your not getting a performance loss, I'd just leave it alone

Also- the early gasket kits had a restrictor gasket on one of the heat risers to form an imbalance from one end of the pipe to the other to cause a flow thru the heat riser- might want to search that.
_________________
some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[EverettB]

[FL-Frank]

Thank you very much! Very informative!

[williamM]

Had it wrong on the operation- but the PO got the idea. And wired it for full heat at a loss of power-which would explain why vw didn't do that.

your Pic speaks a thousand words.


My first car was a stock 54 - 3 fold- beetle. So guess I forgot how to run one since 1966.--

Hint- don't get old folks.
_________________
some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[John Moxon]

[williamM]

[Elrick]

I'm using my air cleaner from removed my original engine 1200 CC engine that came w/ my '63 Ghia. The engine it's on now is a 1600 CC I built many years ago. Seems to work fine but I wonder if it's undersized at all for the slightly bigger engine. It's hard to get it tight enough on the 34 PICT carb. probably could use a spacer of some kind. I really like the oil bath filters.

[FL-Frank]

[Elrick]

Battery is under the back passenger seat.

The tin around the engine is from a '74 1600 so maybe that's why the pre-heat tube comes from the right side. I had to get creative to make the tube work, but it seems to work pretty well. The crankcase vent. tube is a little long as well.

[FL-Frank]