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MGB Head gasket R&R goes on...

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DrEntropy

DrEntropy

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and on and on. Valves lapped, new springs, copper/steel "sandwich" gasket found to replace the "new, improved" Payen piece of drek which failed immediately.

Head reinstalled yesterday, Permatex copper "Spray-a-Gasket" on the REAL gasket. Thought about filling coolant but decided to do the valve lash first. All went well until the number two exhaust. As I tightened its lock-nut it felt "soft." Then recalled one of them having been an "iffy" snug-down in the past. This time it became plain which one that was. Now waiting for a replacement for the adjusting screw and nut. Glad not to have poured the coolant into the engine, as it may take relieving the head bolts and nuts holding the rocker shaft. But I think I can "cheat" it, recall doing similar in the past.

Side note: In the hovel ~someplace~ is a rocker shaft assembly, there's an entire engine disassembled and stashed here. Searched a couple hours for that assembly with no joy. Called Moss this AM and ordered a few of the adjusters and nuts along with other bits-n-pieces I usually forget to request. The errant rocker assembly will make itself visible a few days after the new one arrives and is installed, I'm sure. o_O
 
Wouldn't be so bad, but with accumulation and parts from many vehicles, it gets hard to find the one piece you know you have. Then you buy and find them all.
 
Got the replacements, not pleased with the quality of the jamb nuts. 5/16-24 but "wobbly" on the screw threads. Have put a standard 5/16" NF on the screw and set lash. Want to change oil & filter before firing it up.

The 60-year-old jamb nut and its remains found wrapped into the screw:

jambnutStripped.jpg
 
Got tired after 60 yrs, not bad.
 
I've fifty replacements coming: Grade-5, ASTM/ASME... real jamb nuts. Not some bargain third-world recycled bean cans.
 
Good buy! If one stressed enough to peel threads, the others might be close. Saw a post elsewhere, where someone was told to buy a specific British part because of metal problems elsewhere. The person still bought unkown. Anymore today you can't use price savings for longevity
 
Very likely I'll be ordering future parts from Rimmer. Everything from them so far has been without issues.
 
I find them to be good.
 
Did you check the condition of the bushes in your pedestals? It's amazing how many times that is ignored and people wonder why they can't get repeatable clearances and find out that the rockers are wobbling with worn bushes and worn shaft - I guess because the rockers shaft comes off as an assembly there is a tendency to assume it is OK (and it usually isn't).

Too bad about the locknut! That is usually over tightening in the past. The threading on the adjusting screws isn't a wear item so the fact that the new nuts are loose on them is another offshore parts absurdity. And at $1.69 for new screws, I wouldn't take replacement screws seriously either.
 
Did check rocker bushings and shaft, well inside acceptable tolerances. I've seen many so worn the bushings were ovaled and the shaft dig into by more than a few thou.
Bill said:
Too bad about the locknut! That is usually over tightening in the past. The threading on the adjusting screws isn't a wear item so the fact that the new nuts are loose on them is another offshore parts absurdity. And at $1.69 for new screws, I wouldn't take replacement screws seriously either.
Click to expand...

The original nut felt "iffy" as I recall, when last I ran the clearances. Still waiting for the good ones to arrive, the loose-fitting ones are already in the File 13 As for the $1.69 screws, not gonna use 'em. if I still had easy access to Rockwell testing I'd file a flat in one and test it just for S&G.
 
Haven't fired it up yet, need to drain the oil & change the filter. Did put a new set of plug wires, cap and rotor on it. Also replaced all the valve adjuster nuts.

Some "life" events have interfered and interrupted the job.

Another thing done while into the head refresh was to replace the silly O-ring "seals" (all but two were M.I.A. anyway) with these:

1883sm.JPG
 
Progression between interuptions. Better known as life events, because you say family someone gets snitty. Good job, seem to be getting it done on the safe side. Has taken me 4 days to change a crank sensor on my Yellow Rover and today I saw facia ripped of from wind.
 
"Roseanna Roseanna-Danna"!!!

(reference to ancient Goddess of Truth šŸ˜‰ )
 
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