AirSpeed VW Community Forums

General Forums => VW Club Corner => Ask the DVKK => Topic started by: Thomas on May 26, 2012, 10:02:51 PM

Title: Icing
Post by: Thomas on May 26, 2012, 10:02:51 PM
Had this happen twice now. After driving the 36hp for about 15-20 minutes the car starts to run crappy and dies. If you try to start it's like the carb is flooded. If you let it sit for 15-20 minutes it starts backup. The intake manifold below the carb is ice cold and I have seen sweating in that area. I'm sure it is an icing problem and after looking on the internet it would seem that the heat riser tube is plugged so I removed the intake manifold. It was all clear so that is not the problem. The motor is bone stock except for being updated to 12 volt. Does anyone have any ideas that what could also cause this icing problem. Thanks Tom
Title: Re: Icing
Post by: 70's Looker on May 27, 2012, 12:08:21 AM
you should ask zundfolge haha pm sent  :)
Title: Re: Icing
Post by: Thomas on May 27, 2012, 08:42:41 AM
Woops sorry I thought it went into general forum. After taking off the intake and finding out it is clean I started to do look for ideas on the internet (was up way too late last night). On Samba they talked about the distance that the peashooters should go into the muffler as being critical for how the vacuum effect works on the preheater tube. After looking at mine I was about an inch and a quarter to short on that distance. I'm hoping after reinstall the manifold and adjusting the peashooters this will solve the problem. Has anyone else ran into the peashooter distance problem before?
Title: Re: Icing with PICS
Post by: Thomas on May 27, 2012, 05:23:04 PM
After putting it back together I adjusted the pea shooter in until I got the right flow (helps if you have a FLIR Camera you can use). Below are some thermo shot before and after.
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Fi790.photobucket.com%2Falbums%2Fyy188%2FThomas1965_bucket%2FIR_0240.jpg&hash=ab8014e3ca3e28857b8b64e7fcd12f9abe16ff04)
Driver side
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Fi790.photobucket.com%2Falbums%2Fyy188%2FThomas1965_bucket%2FIR_0238.jpg&hash=42eff3037522e9e2bb8869dffd928be02ac1faca)
Pass side
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Fi790.photobucket.com%2Falbums%2Fyy188%2FThomas1965_bucket%2FIR_0236.jpg&hash=a0a98d59a6de563f00284c8f1e6e7a9ef0dd4e86)
Intake below carb
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Fi790.photobucket.com%2Falbums%2Fyy188%2FThomas1965_bucket%2FIR_0268.jpg&hash=4b6c41d3a586c6b056612d9b35491279c862e69b)
Driver side
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Fi790.photobucket.com%2Falbums%2Fyy188%2FThomas1965_bucket%2FIR_0266.jpg&hash=832bf70cef64ab41b55753604092b181eab9f4e6)
Pass side
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Fi790.photobucket.com%2Falbums%2Fyy188%2FThomas1965_bucket%2FIR_0264.jpg&hash=19938a2c4d48499227aa4c3aa741e1ee6a51fdd1)

The position of the pea shooter in the muffler makes a big differance.
Title: Re: Icing
Post by: buddy boy on May 27, 2012, 06:57:06 PM
cool!!... do you ever use it for ghost hunting?...hehe
Title: Re: Icing
Post by: Jodasa on May 27, 2012, 09:52:00 PM
Thanks for posting this Thomas. Awesome.
Title: Re: Icing
Post by: 52 split on May 28, 2012, 06:04:52 AM
ok   what  distance in should they be? and what point are you measuring from? . thanks
Title: Re: Icing with PICS
Post by: Bubba on May 28, 2012, 09:00:22 AM
After putting it back together I adjusted the pea shooter in until I got the right flow (helps if you have a FLIR Camera you can use). Below are some thermo shot before and after.

The position of the pea shooter in the muffler makes a big differance.

Those are good information shots, but if I can make a suggestion...

If you are doing before and after thermographs, it helps to maintain the same temperature scale throughout.  That way, you can compare apples to apples.

Cheers
Title: Re: Icing
Post by: Thomas on May 28, 2012, 12:23:10 PM
From what information I found on Samba it should overlap by 1/4" that is how far the tube should be inside the pea shooter. With the pea shooter off I measured to the end of the tube in the muffler and the calculated with the lenght of the pea shooter how much should be outside the muffler to give me the 1/4" overlap inside. I found that I put mine in a little more then the 1/4" overlap to get the final temps. It might be different depending on what type of pea shooter you have. As far as the settings on the gun I had the temp range on auto as I was just using it for the spot temp but that is a good idea for next time as the colour changes would show better.
Title: Re: Icing
Post by: Bruce on May 31, 2012, 10:59:41 PM
I don't think you're done yet.
Is the left tail pipe the one you are adjusting?
In the second pic, the right heat riser is at 101º, but in the 5th pic it is only 56º.  I would expect them to be the same.
The right heat riser pic shows that more heat is being conducted up from the muffler than what is being delivered by the exhaust flow from the right side.