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  #11  
Old 01-09-2013, 08:59 PM
SteveH SteveH is offline
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Jeff,

I bought a rebuilt-25K-ago 2F recently that had uneven compression, and 3 valves had zero (or negative) clearance. Ouch. After adjusting, the compression came back up (mostly), but don't wait to check your valves. This guy waited too long. At this point, I don't know whether to just run it and hope the valves re-seat, or to have the valves redone, again.
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Old 01-10-2013, 05:27 PM
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Rzeppa Rzeppa is offline
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Jeff,

I bought a rebuilt-25K-ago 2F recently that had uneven compression, and 3 valves had zero (or negative) clearance. Ouch. After adjusting, the compression came back up (mostly), but don't wait to check your valves. This guy waited too long. At this point, I don't know whether to just run it and hope the valves re-seat, or to have the valves redone, again.
This 2F pulls REALLY strong so I doubt there are any issues like that. It will do 55 up Mount Vernon Canyon, which is pretty amazing, especially for a fully smogged 60. I have about 3-4k miles on it since the rebuild (which did include a head job with new valves and re-cut seats). But typically the cam will wear a bit before it work hardens to the lifters and the clearance will diminish a bit. Hugh said that they had deliberately adjusted it a bit wide to compensate for that. I am due a free adjustment if I want to drive it all the way out to his shop in GJ...
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  #13  
Old 01-10-2013, 06:25 PM
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Isn't the "coasting richer" circuit in the carb supposed to add a fuel to reduce the lean condition on decel? The rest of the carb may be performing great but it may be worth checking the function of the one circuit. I think it's entirely internal on the carb and can't be plumbed wrong with tubing.

It might be the same issue causing the loud pop on Telly's 40 on shutdown.
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Old 01-10-2013, 08:22 PM
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Isn't the "coasting richer" circuit in the carb supposed to add a fuel to reduce the lean condition on decel? The rest of the carb may be performing great but it may be worth checking the function of the one circuit. I think it's entirely internal on the carb and can't be plumbed wrong with tubing.

It might be the same issue causing the loud pop on Telly's 40 on shutdown.
My issue is an A-B comparison vis a vis the carb. My issue was not present with the prior to the motor rebuild, and is present after. I installed the carb the day before I drove toward Moab and had no issues with backfiring upon negative acceleration during that drive.

As I wrote, I need to (1) check valve adjustment and (2) replace the muffler with holes and possibly (3) check all the emissions subsystems before I come here and ask for advice.
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  #15  
Old 01-18-2013, 12:11 PM
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My 78 was originally from California and still has all emissions installed. One thing is does not have is a catalytic converter. Did the rig originally come with one? I'm wondering if not having a cat may be contributing to the exhaust backfire. Doug
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  #16  
Old 01-18-2013, 12:25 PM
SteveH SteveH is offline
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Doug - the emission sticker under the hood should say 'non catalyst' on it - and unless it was a very late '78 that was '79-spec, it should be cat-free. Ignore the 'unleaded fuel only' sticker - that doesn't indicate the presence of a cat. I'm pretty sure you have a pure '78 model year truck.
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  #17  
Old 01-19-2013, 09:07 PM
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My 78 was originally from California and still has all emissions installed. One thing is does not have is a catalytic converter. Did the rig originally come with one? I'm wondering if not having a cat may be contributing to the exhaust backfire. Doug
Both federali and Kalifornia spec Land Cruisers did not get cats (and the smaller fill hole ) until the official 1979 model year. Interesting factoid: Most years, the "official" cut-in date was the September build month (example, 1977 model year started with September 1976 build date). However Toyota messed with this several times. Examples include the cutoff between the 1978 and 1979 build year - a December 1978 was a 1978 and a January 1979 was a 1979. Another example was 1990, another calendar cutoff. Yet the first FJ Cruisers offered in Februaray 2006, were "officially" 2007 models. Go figure?
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