9m 1972 911S repair & restoration - back to original or not?
#91
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The cylinder heads are not in bad condition, apart from some strange profiling on the top of the non-original exhaust valve guides which was the cause of all the valve stem seals running loose on the valve stems. The guides will be replaced. Also spotted on this head is a slight dink in the edge of the combustion chamber from previous rough handling; flaws like this will all be carefully hand dressed.
#92
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The pistons and cylinders definitely have their own story to tell. One odd piston on #1 cylinder, pitting & corrosion in the cast iron biral bores as well as the expected running scratches. With the odd pistons that have different compression heights and dome volumes you wonder how the engine ever managed to run properly?
#95
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The good news is that the crankshaft seems to have survived the years of abuse coming away with minor corrosion marks and a few scratches. If it passes the crack test we think a light polish will have it more than serviceable.
#96
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And so finally we get down to the original "4R" crankcase. Again it looks like #1 cylinder has a story to tell because the two lower studs on this cylinder have been replaced with non-standard stainless steel turned cylinder head studs, as seen in comparison to their adjacent standard studs. Provided the case measures straight and true, all these head studs will be removed from the case, the threads in the case will be repaired with time-serts and 24 new cylinder head studs will be fitted.
#99
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More work preparing the engine parts today, first job to remove the cylinder head studs.
This revealed an interesting repair on the lower two studs for #1 cylinder which comprised of a pair of crudely machined threaded studs which screwed into oversized tapped holes in the crankcase. Of course, as is usually the case with magnesium crankcases, removing the other studs caused a few of them to pull the threads in the case (which was probably the root cause of the above repair) which will be rectified by using time-serts to repair and strengthen all 24 stud threads.
The 632XXXX numbers on the case confirm the originality of this 1972 2.4S engine, type 911/53.
This revealed an interesting repair on the lower two studs for #1 cylinder which comprised of a pair of crudely machined threaded studs which screwed into oversized tapped holes in the crankcase. Of course, as is usually the case with magnesium crankcases, removing the other studs caused a few of them to pull the threads in the case (which was probably the root cause of the above repair) which will be rectified by using time-serts to repair and strengthen all 24 stud threads.
The 632XXXX numbers on the case confirm the originality of this 1972 2.4S engine, type 911/53.
#100
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Meanwhile in the paint booth the bodyshell was having some of the hidden cavities etch primed in preparation for refitting the heater silencer tubes into the sills and re-welding in the access panels. This process is necessary when e-coating a shell because the dip process uses acids which would destroy the heater tubes if left in place.
Also primed are the torsion bar tube, battery box and LHD only "smugglers box" for the aircon unit.
Also primed are the torsion bar tube, battery box and LHD only "smugglers box" for the aircon unit.
#101
Racer
Why did I pick Sepia Brown and Narrow Body?
- Last Saturday I visited 9M in Warrington and seeing the quality of the work being done by the 9M crew I soon realised this car will be better than new. It's body will outlast me, and I plan on staying on this planet for a good while more. To make it into an ST now would do it an injustice. Should I not be happy with it when it's complete it would be a lot easier to go from narrow to wide and an ST Colour than the other way round. There are few enough 2.4S's left alive, and fewer with the Oil Tank opening on the back wing.
- Like little old ladies who collect cats, I've managed to collect a number of ex race/rally 911s over the past 10 or more years. One is a 1985 based RHD Rallycross Car. Another is a RHD 1974 2.7 ( not RS ) that a previous owner built for the track by upping the engine to 2800cc and fitting Webbers. He also fitted wide body steel turbo wings front and back and gutted the interior. Finally there is a 1970 911T that someone sent to Tuthills to convert it into a Rally Car, but he also made the body look like a 964 by usung fiberglass 964 Panels. This was done in the early 1990s when 964s were the current 911 model. Any of these cars could be made into an ST Replica without killing another 2.4S. I feel obligated to preserve the originality on ZT 911, even if I dont exactly love the colour.
- For fun I have a Gen 2 GT3RS, and for serious fun I race a 993 RSR.
- I am absolutlely and totally car mad.
- Last Saturday I visited 9M in Warrington and seeing the quality of the work being done by the 9M crew I soon realised this car will be better than new. It's body will outlast me, and I plan on staying on this planet for a good while more. To make it into an ST now would do it an injustice. Should I not be happy with it when it's complete it would be a lot easier to go from narrow to wide and an ST Colour than the other way round. There are few enough 2.4S's left alive, and fewer with the Oil Tank opening on the back wing.
- Like little old ladies who collect cats, I've managed to collect a number of ex race/rally 911s over the past 10 or more years. One is a 1985 based RHD Rallycross Car. Another is a RHD 1974 2.7 ( not RS ) that a previous owner built for the track by upping the engine to 2800cc and fitting Webbers. He also fitted wide body steel turbo wings front and back and gutted the interior. Finally there is a 1970 911T that someone sent to Tuthills to convert it into a Rally Car, but he also made the body look like a 964 by usung fiberglass 964 Panels. This was done in the early 1990s when 964s were the current 911 model. Any of these cars could be made into an ST Replica without killing another 2.4S. I feel obligated to preserve the originality on ZT 911, even if I dont exactly love the colour.
- For fun I have a Gen 2 GT3RS, and for serious fun I race a 993 RSR.
- I am absolutlely and totally car mad.
#103
Racer
"We think a light polish will have it more than serviceable. "
Colin , my Irish attitude to life is seemingly rubbing off on you, now see what you can polish the barrels to and a bit of filler on the cams !
Colin , my Irish attitude to life is seemingly rubbing off on you, now see what you can polish the barrels to and a bit of filler on the cams !