Smiffo wrote: ↑27 Oct 2022, 16:13
Hi Stuart.
When this is complete, do you think you could give a rough breakdown of costs?
Not so that we can all gasp in horror

, merely to ensure I ( when I get there ) walk into it with eyes open.
I've often looked at most of the cost being in labour for rebuilds, but maybe that assumption wasn't too accurate.
Let me say right now. How long is a piece of string? I know that is not very helpful to you, Steve. But how deep do you want to go? I'm in over a grand at present. Will make a tally up on finish. But l did buy two recon heads, with new valves etc, for 400 quid.
Any proper rebuild take hours of work. But the pro's have the tools and the know how. Whereas, today, for instance, l introduced myself to the world of helicoils and spent an afternoon famnying about.
The sump plug was weak so decided to do a drill out, tap and insert a helicoil. Three hours' work for me...two of those hours filled with dread and uncertainty!

Likely 15 mins for a pro.
I bought an appropriate kit from eBay, which included the correct size drill bit, insert and tang breaking tools, a correct size tap plus ten helicoils. Being a dimwit l didn't ask for a reduced shank drill bit. So the supplied bit, 14.3mm or 9/16", didn't fit any of my drills. A short drive to a local Goodwin's tool shop gave me a blacksmith's drill bit with reduced shank. So l have just saved you 8 quid! See what l mean.
The story in photo's
Block strapped to table. An old gudgeon pin used as a guide...stuck in position using blue tack.
Drilling out old thread, using an old gudgeon pin as a guide.
New shiny hole.
Getting the tap as true as possible. Mostly by eye, and using a plastic ruler to view horizontal and vertical right angles.
And through we go. Note small box to collect swarf cuttings. Silly really.
Wrong, wrong, wrong! The instructions were best useless. No mention of adjusting collar on insert tool to help keep light pressure on base of helicoil. So that's what the allen key is for!
The kit.
Fourth attempt coming up.
Cutting the helicoil to correct depth before fourth insert attempt.
Hoorah!
The internal side. The helicoil has jump a couple of threads. Easily remedied with a turn to tighten coil and pull back.
Tang knocked off .....sitting lower in case
Success. Beer time!