What might have been done to my engine in the past?


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Well-known member
Sep 5, 2018
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My Car
1971 Cobra Jet 429 Ram Air C6 auto 3.50 traction loc
Hi All,

Been a while and still working my way through a comprehensive servicing of my 429 CJ RA C6 Mach 1. Life gets in the way, as it does, and it's only recently that I've got a set of lifts to give me semi decent working room under the car.

I just cleared some oil and crud from the engine block (a few leaks to take care of) and noticed (of the ones that are easily seen) that 3 of the core plugs are brass. I presume, therefore, that all 6 will be replacements and that it must mean that the engine has been removed at some point in its life?

From what I've been able to work out the car covered 45,000 miles in the first 14 years of its life (has spent all its time in the UK as made for export) and then only just over 7,000 miles in the last 35 years (presumably that's why there are a few oil leaks from seals etc drying up though little use?).

If the engine was removed then it must have been within those first 45,000 miles I'm guessing?

My questions are these. If you pulled an engine to replace the core plugs, and assuming it was otherwise basically sound (I can't confirm that of course) then what other parts would you replace at the time? I'd imagine the water pump for sure, belts etc but what else? I've no paperwork at all regarding this.

Secondly, would there be any other indicators, that I might be able to see fairly easily, to show if the engine had been torn down at all or rebuilt? I don't plan on going deep into the engine myself as it doesn't seem to need that but it definitely needs properly tuned up for sure.



Last edited by a moderator:
Jan 4, 2016
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My Car
1973 mustang mach1 clone
FMX auto
393 stroker
If it was mine, I would replace the oil pan gasket, oil pump, oil pump drive shaft and  a good double roller timing chain. Its good insurance to keep the motor alive for many more years.