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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: My 86 on January 29, 2017, 03:39:13 pm

Title: 305 overheating
Post by: My 86 on January 29, 2017, 03:39:13 pm
I have this 86 GMC truck as a daily driver. Late this fall it has started to overheat. when I first start the truck up and head for work the temperature gauge will eventually peg to 240 for a brief time then it goes back down to 200 and all is well. I have changed the thermostat 2 times thinking I might have a bad one but it does the same thing every time. It is a 195f thermostat. Also replaced radiator cap last summer. It also has a leak along that seam below the filler cap. Not sure how big of leak but I do have to add coolant offen. I've tried stop leak 2 times or more but I still have to add coolant. I may have a couple different problems going on here. Plugged radiator or bad water pump??? All comments and advice is appreciated.
Title: Re: 305 overheating
Post by: VileZambonie on January 29, 2017, 07:59:18 pm
Your radiator is probably plugged and since it's leaking that would be a good place to start.
Title: 305 overheating
Post by: philo_beddoe on January 31, 2017, 01:14:53 pm
Yup, always radiator.  (Usually always)