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F-head Head Gasket Issues.......puffers Puffing Noise

Discussion in 'Early CJ-5 and CJ-6 Tech' started by tomtom, Oct 7, 2019.

  1. Oct 7, 2019
    tomtom

    tomtom Sponsor Sponsor

    Huntington Beach, CA
    Joined:
    Jun 20, 2007
    Messages:
    127
    I almost threw in the towel on the Rubicon trip this year at the trail head because of this noise…..but here’s the whole story…..


    The most stressful part of running the trail for me is the Highway 50 drive Sunday morning from South Lake Tahoe to the Wrights Lake road. Tons of traffic trying to go fast and steep hills add up to not a fun drive with your F-head. Soon after I was going, I started hearing a weird noise. I pulled over a few times to try to figure out the source, but the noise would go away pretty quick once I pulled over. Once rolling again at highway speed (or as close as I could get to it), the noise would start again. Repeated this 5 or 10 times on the way to the trail head. The group helped search on a few of the stops and Jonah finally tracked it down to leaking compression coming from the rear head bolt. You could feel it. When we finally got to the trail head I had decided I was going to spend the night there and then head home the next day. I had a family trip planned the next week in Flagstaff and Sedona and needed the jeep and figured I might have time to fix it if it was just the head gasket. I honestly didn’t realize until then how important this jeep is for fun…. it was the center piece of two straight weeks of activities. Well, instead of staying there I got talked into going in to Ellis Creek for the first night with the group. I intended to turn and head back and out after that…but, it ran fine running at trail speeds. No noise, normal temps, no milkshake oil, nothing out of the ordinary, so decided to keep going. Never heard the noise again until 3 days later and 2 minutes into the drive back to South Lake Tahoe on 89. It puffed its way back to the Motel 6 and flat towed home the next day.


    By the time I got home I’d had a few days to think about it and the upcoming Arizona trip and I decided to pull the leaking head bolt and seal it with sealer and a copper washer. Just a temporary thing for the trip and I figured worst case I’d have a real good excuse to get a V6 or V8 after. I never checked the torque on the head bolt on the trail because the valve cover had been placed such that I couldn’t get a socket on it. When taking the bolt out it felt under torque spec but still tight….. I suspect I never re-torqued it after the last assembly. Well, the washer and sealer ended up working out great, although towards the end of the trip it was definitely burning coolant. Still nothing out of the ordinary, except driving at road speeds it was starting to run a little hotter and letting out some white smoke. Oil on the dip stick still looked good.


    Finally got a chance to pull it all apart and as you can see from the photos, it was the head gasket. I checked both the head and block for cracks and it all looked good. Looks like it had a lot of coolant in #4 as well. Most of the head bolts thread into water jackets and I think the sealer on the threads finally gave. When I drained the oil, a lot of coolant came out first, the oil was floating on it.


    It’s back together now and is running like its old self which is good news, although the thought of a couple extra cylinders was really starting to grow on me.

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    Hellion, 47v6, 73 cj5 and 2 others like this.
  2. Oct 7, 2019
    ITLKSEZ

    ITLKSEZ Volvophilic

    Post Falls, ID
    Joined:
    Aug 13, 2015
    Messages:
    3,306
    Blasphemy!!! :D
     
    73 cj5 likes this.
  3. Oct 7, 2019
    jpflat2a

    jpflat2a what's that noise?

    Riverside CA
    Joined:
    Jul 30, 2003
    Messages:
    7,797
    Sorry to hear Tom.
    Glad no serious damage.
    A V6 can wait, 4 bangers are fun.
    (says the guy who converted to V6 many many moons ago)
     
  4. Oct 8, 2019
    Keys5a

    Keys5a Sponsor Sponsor

    Florida Keys
    Joined:
    Jan 23, 2014
    Messages:
    2,216
    Did that rust through or burn through the fire ring of the head gasket? It almost looks burned through.
    -Donny
     
    Hellion likes this.
  5. Oct 10, 2019
    tomtom

    tomtom Sponsor Sponsor

    Huntington Beach, CA
    Joined:
    Jun 20, 2007
    Messages:
    127
    I don't think it rusted through, I figured it burned through as well. Other than the head bolt possibly being below full torque, I don't have any other guesses on what happened.
     
  6. Oct 10, 2019
    modadds

    modadds New Member

    Sweetwater, Texas
    Joined:
    Feb 25, 2014
    Messages:
    33
    Head may be warped, It needs to be machined and leveled along with the top of block if possible, in order to have two good mating surfaces.
     

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