09-30-2022, 09:06 AM | #1 |
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Smoking at idle
My 350 is smoking blue smoke at idle. Once I rev it above idle it clears up. I have a 600 edlebrock. Fuel pressure is 5 engine has been rebuilt
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09-30-2022, 10:35 AM | #2 |
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Re: Smoking at idle
Just like I posted in your other thread.
If you’ve been fuel washing your cylinders then your cylinder walls have been glazed and the rings can’t control the oil. And fuel in your oil causes bearing problems. You might be looking at a complete refresh. Do a wet/dry compression test. What do your plugs look like? |
09-30-2022, 04:45 PM | #3 |
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Re: Smoking at idle
The engine is rebuilt. I have only driven it about 50 miles That would not be enough to mess the rings up
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09-30-2022, 05:53 PM | #4 |
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Re: Smoking at idle
Any chance the rebuilder skipped the step labeled "Install valve guide seals" or otherwise messed up that step?
2nd the suggesting to check the plugs. Might tell if the oil issue is with the whole engine or just a couple of cylinders. |
09-30-2022, 06:32 PM | #5 |
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Re: Smoking at idle
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09-30-2022, 07:32 PM | #6 |
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Re: Smoking at idle
Plugs are black with soot and smell like gas. I am building another carburetor and will try it tomorrow. Then a compression test
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09-30-2022, 07:53 PM | #7 |
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Re: Smoking at idle
Another question If it was the rings or valve guides wouldent it smoke when the engine was reved up? I had a guy from work stand behind it then I reved it up to about 1500 rmps and held it, no smoke but once back down to an idle it started again.
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09-30-2022, 08:47 PM | #8 |
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Re: Smoking at idle
Get a good carb, one that you know is right not one you rebuilt. Not saying you aren't capable of building a carb just that there are too many things that can go wrong and you need to eliminate the carb from being the problem. If you get a good carb be sure to change the oil no matter if it does only have 50 miles on it. I wouldn't drive it until I did get a carb if I was you.
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09-30-2022, 10:12 PM | #9 | |
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Re: Smoking at idle
Quote:
With smelly plugs you likely have fuel contaminated oil too. Another carb might not help as the damage may already have been done. Not a good scenario but the sooner you pull it apart the better. |
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10-01-2022, 11:50 AM | #10 |
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Re: Smoking at idle
When it was rebuilt did you change valve covers?
Some aftermarket covers don't have the correct oil baffle / breather and allow oil to be pulled past the valve guides under high vacuum conditions. I had this problem once with an old set of M/T covers and it did exactly as you describe. A picture would help. Found the pic in your other thread http://67-72chevytrucks.com/vboard/s...d.php?t=838462 Last edited by MySons68C20; 10-01-2022 at 12:09 PM. Reason: added link |
10-01-2022, 06:54 PM | #11 |
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Re: Smoking at idle
Leaking intake gaskets can cause blue smoke at idle. It's happened to me before. Now I torque them to spec with a torque wrench instead of guessing like I used to.
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10-01-2022, 07:54 PM | #12 |
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Re: Smoking at idle
FIXED!!!!!! It was the carburetor. I had another 600 edlebrock in my parts. I put a kit in it and now there is no smoke at all and it idles a lot smoother. I did not notice the exhaust tone before but it was real raspy. Now it is smooth as butter and idles so nice. Thanks for all the replies
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10-03-2022, 11:33 PM | #13 |
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Re: Smoking at idle
I'm glad you got it fixed and I doubt you damaged the motor but it would be a good time to change the oil just to be on the safe side.
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10-04-2022, 07:26 AM | #14 |
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Re: Smoking at idle
Yes I already did. Thanks
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