Fitting Heat Riser Tubes

[Danwvw]

I have not actually done that yet just did those test with some fresh air heater hose to the carb full on. Probably won't have that until I put this engine in the bus which I don't plan on anytime soon. The plan for hooking up the heat is just as it would be with the stock oil bath air cleaner and maybe run the 69-70 lever flaps to control it even though it's a 1971 Bus with a failed wax pellet thermostat.

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

"williamM" The heat risers came today, Look Good. Looks like I am going to have to remove the manifold to get them in it. They go in about 1/2" then get really tight.

What I need to figure out now is what I should put in around the riser tubes to make them seal and can I cut them off a little more?

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

I was thinking the orange silicone RTV gasket sealer High Temp would be good. And. I was thinking of putting a restricted gasket at the muffler flange but am not sure which end it goes on.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Lingwendil]

I think if you drill the intake to where the risers will fit in all the way and snug, and then possibly use orange RTV or muffler putty to seal it would work fine. There isn't much pressure through the risers when they are clear and maintained.

Small hole in the gasket goes on the left (the side with the tube running down into the muffler) is how I've always done them, but it's been a while since I rocked a centermount... when done this way my risers were always super hot and burned off their paint rather quickly. Too bad these don't come in stainless.

Running the stock style oil bath with a cable control off of the flaps would be a great way to do things in my opinion, I prefer those to the wax pellet cleaners. Looks like you are almost done! Should work great once it's all done up.

Almost bought a zenith at the swap yesterday, but the guy didn't want to let it go for less than $100, and it had a gritty throttle shaft, so I passed. I kind of want to grab one up for a single port build at some point, and put together a nice simple rig...
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73 super beetle thread http://www.thesamba.com/vw/forum/viewtopic.php?t=649622 Back on the Road!

Modify your Kadrons for SVDA http://www.thesamba.com/vw/forum/viewtopic.php?p=8115884#8115884

Cast iron VJU4BR8 SVDA reference thread- https://www.thesamba.com/vw/forum/viewtopic.php?t=...mp;start=0

Need replacement filters for original Kadron aircleaners? WIX #42087 is a perfect fit, as is Napa Gold #2087!

[Danwvw]

I got this Zenith: Single Zenith Carburetor. Ad, from the classifieds here on the Samba, It is in fair condition. I took it apart and greased all the screws and cleaned the jets but not really a re-build, has the old gaskets needs orings etc. Base is a bit rough around the butterfly but it's getting better with use, but it tunes and works flawless.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

Had to cut the riser tubes about 3" shorter or so to get them in. Sealed With the Permatex Ultra Copper Gasket Maker.
Had a few problems with fit. Did not have a restricter gasket so made one with a bronze flange and a washer, It's about a 1/4" hole now, sits there well can't go anywhere but I used the Permatex on it too.
Not real happy with this set-up, I think it will start leaking exhaust fumes at the intake manifold in time, also There is not anything to brace the manifold and Zenith Carburetor yet. Need to find a brace or something for that. Will give it a test start and run and collect new temperature readings in a couple of days after that 700 Degree F silicone set's.

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Lingwendil]

I would bend a piece of steel to run between one of the fuel pump mounting studs and one of the carb base studs, should brace it just fine. To prevent future leaks maybe stake the tubes in place all around the edge of where they enter the manifold? Maybe use an alloy brazing rod that sticks to aluminum, and braze them on?
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73 super beetle thread http://www.thesamba.com/vw/forum/viewtopic.php?t=649622 Back on the Road!

Modify your Kadrons for SVDA http://www.thesamba.com/vw/forum/viewtopic.php?p=8115884#8115884

Cast iron VJU4BR8 SVDA reference thread- https://www.thesamba.com/vw/forum/viewtopic.php?t=...mp;start=0

Need replacement filters for original Kadron aircleaners? WIX #42087 is a perfect fit, as is Napa Gold #2087!

[Danwvw]

Yeah, I ordered some 8mm all thread and some M8 X 1.25 connecting stand off nuts, I will try making a brace that connects at the fuel pump and the carb base with them.

I like the idea of brazing the riser tubes but I don't think there is any kind of metal rod that will braze to aluminum. I wonder if the temperature of brazing them is low enough for a BERNZOMATIC CUTTING, WELDING AND BRAZING TORCH KIT they only cost about $60. May-be the Aluminum brazing rod from tractor supply.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[mikedjames]

if you use the stock air cleaner setup to feed the hot air, the heat is provided at idle and removed at WOT as it is controlled by the thermoswitch and the flap is operated by manifold vacuum.
So you do not feed the engine too-hot air and boil the fuel and reduce power at WOT.

You can use exhaust cement for sealing the heat risers to the manifold.. Works best with slightly undersized tubes.
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Ancient vehicles and vessels

1974 VW T2 : Devon Eurovette camper with 1641 DP T1 engine, Progressive carb, full flow oil cooler, EDIS crank timed ignition.
Engine 1: 40k miles (rocker shaft clip fell off), Engine 2: 30k miles (rebuild, dropped valve). Engine 3: a JK Preservation Parts "new" engine, aluminium case: 26k miles: new top end.
Gearbox rebuild 2021 by Bears.

1979 Westerly GK24 24 foot racer/cruiser yacht Forethought of Gosport.
1973 wooden Pacer sailing dinghy

[Danwvw]