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Radiator needs cleaned or.....suggestions on flushing or get new a one

Discussion in '1982-Present GM Diesel' started by 6.2Blazer, Apr 15, 2002.

  1. 6.2Blazer

    6.2Blazer 1/2 ton status

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    Since the weather has finally started getting warmer, the 6.2 in my '90 K5 has been running on the warm side and can get hot in a hurry when climbing long steep grades out on the trail. After draining the coolant I looked down into the radiator through the cap opening at there is a lot of the white colored corrosion/build-up along the edge of the core which is most likely the problem.

    I would like to try flushing it out before having to pull it out of the vehicle. Anybody have any good pointers are recommend any certain types of flush? The local auto parts store has some Preston brand flush that requires 3-6 hours of running and is intended for heavy buildup. I was planning on removing the thermostat to speed up circulation through the system and then trying to do a back flush of the system.

    If this doesn't work I might just get a new radiator. Anyplace, brand, ect...that you would recommend?
     
  2. Danno

    Danno 1/2 ton status

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    I'd just have the radiator serviced (steamed) at a shop. The best way to clean a radiator, or so I've been told.

    I've used different radiator flush products in the past, and none of them really did much for heavy crud build-up. Probably good for regular maintenance if you start with a clean radiator, though.

    Something that REALLY made a difference in my truck was switching to a Robert Shaw thermostat. I used part #370-180, which I found at Autozone. $7 for the thermostat. It's a 180F t-stat, and my truck very rarely EVER goes over 200F in the mountians with my foot halfway into the throttle. I've still got the stock radiator too.
     
  3. arveetek

    arveetek 1/2 ton status

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    Diesel radiators are very expensive, from the $400 to $500 range for typical new radiators.

    Do you have a three-core or a four-core? If you only have a three, I'd suggest you have a rad shop put a new four-core section in place of your old one. You will re-use your end tanks, which are the expensive parts, for some reason. It shouldn't cost more than $200 to have this done. A local rad shop quoted me $295 to have a new five-core installed in mine, which I'll probably do someday.

    If you already have a four-core, just pull the rad out and take to a shop to have it rodded out and cleaned up. I think this would be the best thing to do. You can do this with a three-core, but you might as well upgrade at the same time.

    Hope this helps.

    Casey
     
  4. 6.2Blazer

    6.2Blazer 1/2 ton status

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    I checked last night and the factory one is a 4 core model. A friend at a body shop can get me some deals so it would cost $295 for a new one with a warranty. They quoted $200 to recore it.

    What should I expect to pay to have the current radiator rodded and cleaned (assuming I pull the radiator out of the truck).

    I'm going to try running some good cleaner through it and see if it helps any first.
     
  5. arveetek

    arveetek 1/2 ton status

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    My local rad shop said they would rod out, clean, and check for and repair any leaks for $60.

    Casey
     

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