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Author Topic: Exhaust pipe temp  (Read 866 times)

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Offline ironrod60

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Exhaust pipe temp
« on: September 16, 2016, 11:51:53 AM »
In a search I found some discussions about exhaust temps across the 4 cylinders.
My pipes are reading these temps.
From left to right, in degrees F---252, 100, 200, 265.

I've been driving it this way for probably 200 miles. Have I damaged the motor? Or would it be evident?
Can I sync the carbs safely?

Wes
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Online calj737

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Re: Exhaust pipe temp
« Reply #1 on: September 16, 2016, 11:54:53 AM »
I'd suspect you have a fuel problem, especially with cylinders 2/3. Perhaps a weak spark, or coil issue? 100* separation is an indicator of poor combustion. Probably not damaged anything yet, but it probably runs pretty dang poorly-
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Offline flybox1

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Re: Exhaust pipe temp
« Reply #2 on: September 16, 2016, 11:58:18 AM »
Calj in on point today  ;D  I cant get in a post before he fires one off  :P

100deg seems awfully low.  More like heat from other cyls than combustion.
Clear tube test your carb bowls first, to ensure adequate fuel levels.
Timing is probably good since #3 fires, but please check w a light for ignition and advance on both 1/4 and 2/3
Check plug caps to see if resistance is way out.
If they are 5Kohm caps, over 8kohms is getting too high for good spark

« Last Edit: September 16, 2016, 12:00:19 PM by flybox1 »
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Offline ekpent

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Re: Exhaust pipe temp
« Reply #3 on: September 16, 2016, 02:34:01 PM »
100 degrees is basically not firing and if the carb is working and your getting gas into that cylinder your washing all the oil and lube out and could be causing damage to the piston, ring, cylinder and diluting your oil also. It must not be running too good ??
« Last Edit: September 16, 2016, 02:37:36 PM by ekpent »
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Offline Sherif78

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Re: Exhaust pipe temp
« Reply #4 on: September 19, 2016, 01:19:11 AM »
I just recently had the same issue. It was a bad spark plug with a weak spark. It was not running well at all!!
I changed the sparkplug and it runs great now. It's probably a good thing to test the things Flybox1 says too. Could also be a fuel delivery problem.
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