| carburetor choke heater - block off or repair??? [message #265007] |
Tue, 28 October 2014 13:48  |
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Broham
Messages: 204
Registered: March 2013
Location: Detroit, Michigan
Karma: 0
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Senior Member |
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hello all,
As I was digging around my engine bay I found, what I think, is a loose carburetor choke heater. It is easy to move by hand and not sealing at either end, see the red arrows. It also appears as the PO had some problem with it because the vacuum hose under it, green arrow, has been "repaired". I thought I read somewhere this was a very dangerous issue that could cause an engine fire and they suggested blocking it off. Is this correct?
I guess my question are is it supposed to be like this and do I need it. I live in Detroit and us my RV down to the 50/60.
thanks in advance
Todd
Todd
Owner of a 1976 Eleganza II 26’
other toys:
93 Vette
84 Goldwing
and gone but not forgotten
72 CB750 Chopper
96 Caprice Classic
34 Ford roadster
94 Fleetwood
[Updated on: Wed, 29 October 2014 08:17] Report message to a moderator |
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| Re: carburetor choke heater - block off or repair??? [message #265065 is a reply to message #265007] |
Wed, 29 October 2014 09:20  |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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Senior Member |
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Todd,
The picture is good.
Yes, in Michigan you need the choke to work. I suspect yours does, but that "repaired" vacuum line was mis-routed too close to the choke heater tube. Just get a new and longer piece of vacuum hose and dress it away from the hot parts.
You may only use the coach above 50°F, but if you have to start it at those temperatures, a choke will help a lot.
Matt - lives near Sibley and I-275
Broham wrote on Tue, 28 October 2014 14:48hello all,
As I was digging around my engine bay I found, what I think, is a loose carburetor choke heater. It is easy to move by hand and not sealing at either end, see the red arrows. It also appears as the PO had some problem with it because the vacuum hose under it, green arrow, has been "repaired". I thought I read somewhere this was a very dangerous issue that could cause an engine fire and they suggested blocking it off. Is this correct?
I guess my question are is it supposed to be like this and do I need it. I live in Detroit and us my RV down to the 50/60.
thanks in advance
Todd
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: carburetor choke heater - block off or repair??? [message #265067 is a reply to message #265007] |
Wed, 29 October 2014 09:44 |
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John Heslinga
Messages: 632
Registered: February 2011
Location: Edmonton, Alberta, Canada
Karma: 4
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Senior Member |
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Hi Todd
All is not so bad.
Don't consider blocking anything off. Automatic chokes are most convienient! That heat tube going into the manifold is simply friction fit in the choke oven that is bolted to the manifold. If nothing is rotten you will be just fine. Give it a gentle tap to seat it into the oven fitting well. It does not have to be tight, just snug. Then tighten the fitting on the carburetor choke housing. (Again just snug.)
The fire danger you are referring to, is when the tube in the oven is rusted out or the gasket is leaking because exhaust gasses are leaking at two exhaust valves in that vicinity. (and even some flames sometimes) The Vacuum hose is scrap. It will be hardened from the heat and old age. Replace it with a bit longer (or shorter) hose rerouting it to get it away from the hot stuff.
Enjoy your coach
Best regards
John and Cathie Heslinga
1974 Canyonlands 260
455, Manny tranny and 1 ton, 3:70 LS,
Red Seal Journeyman, DTE, BEd. MEd.
Edmonton, Alberta
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| Re: carburetor choke heater - block off or repair??? [message #265068 is a reply to message #265007] |
Wed, 29 October 2014 09:56 |
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John Heslinga
Messages: 632
Registered: February 2011
Location: Edmonton, Alberta, Canada
Karma: 4
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Senior Member |
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Oh by the way!!
Check out the peanut shells in the area. Those are the fire risk!! As you can see, the top of your engine is a great dry dining area for rodents. They sometimes even make a home and move in. Keep that area clear.
I should have also mentioned that the other metal tube going to the choke oven from the top of the carburetor is the filtered fresh air for the choke. It should also be snug in the other end of that oven. There is a very small air (vacuum) passage in the carb moving the hot air that if it gets plugged your choke wont work very well.
Best regards
John and Cathie Heslinga
1974 Canyonlands 260
455, Manny tranny and 1 ton, 3:70 LS,
Red Seal Journeyman, DTE, BEd. MEd.
Edmonton, Alberta
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| Re: carburetor choke heater - block off or repair??? [message #265077 is a reply to message #265068] |
Wed, 29 October 2014 11:58 |
Otterwan
Messages: 946
Registered: July 2013
Location: Lynnwood (north of Seattl...
Karma: 0
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Senior Member |
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It is also wise to check that there is air being drawn through the system. You can just remove the upper metal line at the carb with engine running and check with your finger. There is a little plastic grommet (for lack of a better term) in the air passage between the choke and the carb. Mine was missing, so no air was being pulled through the system, and I had to go through 2 parts carbs to find one. Without it, the choke coil will never heat enough to fully open.
1977 Birchaven, Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to us."
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| Re: carburetor choke heater [message #265092 is a reply to message #265057] |
Wed, 29 October 2014 17:41 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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The fire danger is the gasket between the choke heater and the intake manifold. Remove the two bolts and inspect or replace the gasket. While you have the heater out also inspect the heater tube that is normally buried in the intake manifold. After reinstalling the heater, the two upper tubes just plug in to the heater. They may appear to be loose to you, but just make sure they are plugged in tight.
Scrap the vacuum hose in the picture and replace it. Be careful where you run the new hose. The area around the choke heater extending to both sides gets very hot if the crossover is not blocked., It will melt the new hose.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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