First time at a machine shop

[Brianl289]

Hello all,

I have a handful of machine shops in town that primarily specialize in muscle cars but some claim to have experience with “imports”. I’d like to bring my eta block and head to have the crank/rod bearings inspected, general block inspection as well as the head to see if all of the valves/springs are in good shape as well as if the head is still flat. If needed I was considering having items replaced at the shop unless doing it myself is feasible. Engine internals are the only thing I don’t have any previous experience with.

Engine has about 210k on it. It’s all out and apart as I prepare to reseal and get this engine ready for its next 200k.

I’ve never been to a machine shop and am curious if they are all fairly standard in how they operate regardless of the engine or if I am better off sending these items to a shop out of town.


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[varg]

There's nothing special about an M20 bottom end, any machinist that can handle a cam-in-block american V8 can handle inspecting and measuring the intermediate shaft bearings, but may need to make some tooling to replace them and sourcing the bearings is tough these days ForcedFirebird. I wouldn't want someone not used to dealing with rocker shaft equipped heads disassembling my M20 head with the goofy rocker shaft setup it uses. Such setups are not common in American engines, or even japanese imports and usually rocker shafts are bolt-on; pedestal mounted or similar. The slide-in BMW design is finicky, fragile, and makes removal and installation a pain if the head isn't flat.

[82eye]

had new rings, bearings, rebalance etc done at a standard machine shop. they also cleaned up the head, did a valve job, and a street port. they weren't concerned about the brand at all. they weren't a hot rod shop or anything, they mostly did commercial stuff, both diesel and gas. any honest shop can do it.

i tore the engine down to the block and bare head and took those in. i left pistons/crank and valves/springs in, it came back the same way all cleaned up with the new stuff in. i installed the cam and did final assembly. most things you can do yourself with pretty common tools. don't be afraid of it.

the only thing the machine shop has to be aware of is the intermediate shaft bearing for the oil pump. it's a pressed in babbit bearing, and many newer techs have no idea about them. hot-tanking the block to clean it will kill that bearing.

more edit: missed the ims bearing warning varg mentioned

[Brianl289]

Cool thanks guys. That is very helpful info. I am hoping to swing by one of the local shops tomorrow to chat and feel it out. Hopefully they don't give off any red flags.


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