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removing exhaust heat riser valve

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Old Jan 24, 2014 | 07:51 PM
  #21  
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The heat riser on my 73 is real stiff despite lubrication. This may be a dumb question, but what position is it when open? Handle down? A picture would help.
Fran
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Old Jan 24, 2014 | 09:28 PM
  #22  
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The weight helps pull the flap open.
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Old Jan 25, 2014 | 06:10 PM
  #23  
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As 7T1Vette said just remove the flap from inside the heat riser valve. I did this and it is very easy to do. Best of all it's free. The only investment is your time.
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Old Jan 25, 2014 | 09:33 PM
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Originally Posted by Blue73Shark
The heat riser on my 73 is real stiff despite lubrication. This may be a dumb question, but what position is it when open? Handle down? A picture would help.
Fran
Handle down is open.
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Old Jan 25, 2014 | 11:18 PM
  #25  
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Johnny - 2 caveats here. First, depending on how many miles on that exhaust system, use a little heat and a LOT of PB Blaster on those manifold studs. They'll snap on you in a heartbeat if you just try to twist 'em off cold and dry. WD40 or Liquid Wrench won't cut it. (Both good products but not very effective on really rusted bolts/studs). Number two, if you have a stock Q-jet with hot air choke, you'll need to convert to an electric choke. Without the hot exhaust gasses in the crossover, it'll take years before that choke opens all the way.
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Old Jan 26, 2014 | 01:54 AM
  #26  
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Originally Posted by pacecar620
Johnny - 2 caveats here. First, depending on how many miles on that exhaust system, use a little heat and a LOT of PB Blaster on those manifold studs. They'll snap on you in a heartbeat if you just try to twist 'em off cold and dry. WD40 or Liquid Wrench won't cut it. (Both good products but not very effective on really rusted bolts/studs). Number two, if you have a stock Q-jet with hot air choke, you'll need to convert to an electric choke. Without the hot exhaust gasses in the crossover, it'll take years before that choke opens all the way.
1) I soaked with Liq. Wrench everynight for about a week, no problem getting my bolts out - luckily! I was pleasantly surprised.
2) aha, well I don't know much about the Q-jet, but I'd guess it's stock with manual choke. I'll research switching to electric choke, but (ignorantly) it doesn't seem like something I'm about to try. It seems like alot of others have gutted their risers, would this mean they may already have e-chokes? Since you're in FL, I guess being southern won't help? I'm in So.Cal. never truly gets "cold" here.
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Old Jan 26, 2014 | 01:32 PM
  #27  
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i used the wd-40 rust release, and it worked well, i got it hot and applied it again.did that 2 or 3 times.
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Old Jan 26, 2014 | 01:42 PM
  #28  
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Originally Posted by pacecar620
Number two, if you have a stock Q-jet with hot air choke, you'll need to convert to an electric choke. Without the hot exhaust gasses in the crossover, it'll take years before that choke opens all the way.
As long as you already have a choke that is in good operating condition,not really an issue.The heat riser valve is the first thing that gets yanked on most of my vehicles,the choke opens up just fine.
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Old Jan 26, 2014 | 02:12 PM
  #29  
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The OP has a vette and thinks $30-50 is expensive????????????
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Old Jan 26, 2014 | 06:22 PM
  #30  
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Originally Posted by briankeery
The OP has a vette and thinks $30-50 is expensive????????????
Some people do buy cars on margin. I was one in 1986 when I bought my badly flawed 1979. It had been stolen and hot-wired with the usual consequences. My first Corvette after years of waiting. That was all I could afford at that time. Budgets were tight and repairs were slow to come. But they did eventually. I can't fault the OP. In fact I wish him well!
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Old Jan 26, 2014 | 07:40 PM
  #31  
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Originally Posted by briankeery
The OP has a vette and thinks $30-50 is expensive????????????
A C3 is probably one of the least expensive and most forgiving cars anyone could work on. Parts are dirt cheap and labour is free except for the cold beer. Try a C6 Z06 where headers cost you over 2 grand before you install them yourself and a 2 dollar part on a C3 is now over 200 because of the "corvette tax".
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Old Jan 26, 2014 | 07:54 PM
  #32  
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Originally Posted by CanadaGrant
A C3 is probably one of the least expensive and most forgiving cars anyone could work on. Parts are dirt cheap and labour is free except for the cold beer. Try a C6 Z06 where headers cost you over 2 grand before you install them yourself and a 2 dollar part on a C3 is now over 200 because of the "corvette tax".
Yes and no. This starter was $94.00. Given I drive an L-48 I buy Chevrolet rather than Corvette. An alternator is less than $100.00.

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Old Jan 26, 2014 | 11:32 PM
  #33  
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Evening Paul. A starter like that for A C6 Z06 would be over the 500 dollar mark. Below is a set of headers I have that would make any C3 guy cringe for his two grand back..


I love working on this old thing. It costs next to nothing. It's fun. And I get to keep a 44 year old car alive. I was down at the parts store and asked for a set of valve seals. I think it was 6 bucks....
Try that one on a C6. My first Corvette was a 69 427 and I paid $3200 for it in 1970.
The one I have now cost me a bit more than that, gets only get's 9 miles per gallon, but is worth every penny. My wife said "oh man, only nine miles per gallon. I love this car". She actually meant it. She was as close to drooling as I have ever seen. She actually drove it to the gas station then home then back because she didn't think it could be that bad. It was and you should have seen the smile on her face.


Last edited by CanadaGrant; Jan 27, 2014 at 12:33 AM.
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Old Jan 27, 2014 | 02:42 AM
  #34  
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Originally Posted by briankeery
The OP has a vette and thinks $30-50 is expensive????????????
Yeah I have a vette, but the family still has to eat.
Labor is free, parts are cheap.
But I'm already spending enough replacing enough parts that aren't broke, but "now that the engine is out..." Add up parts, hoses, belts, gaskets, water pump, etc.

Besides...$30-50 can buy alot of cheap beer! (or alot of ingredients for some quality homebrew).

Ima just sayin'
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Old Jan 28, 2014 | 01:48 PM
  #35  
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Default heat riser valve

My heat risers on my 1968 and 1970 have been wired open for more than 20 years. Cold starts, driving no problems.
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