mandatory parts for engine rebuild?

[azmavhockey3]

Im doing Internals, rods and pistons. What parts are mandatory for engine rebuild? I know all the gaskets need to be replaced.Also, head bolts,Crankshaft Seal, Timing Cover Seal,Valve Stem Seal,Connecting Rod Bearing. Anything else? Do i need to replace main bearings?

 

[meicalnissyen]

I would look at them, plastigage them, but if they are clean shiny and in spec, no, id leave em alone
On that note, why are you changing head bolts? Gotta be a better place to spend that money

 

[Maxx Mazda]

Head bolts are TTY, so once they're tightened once they're junk and need to be replaced.

And not replacing the main bearings? Are you kidding me? Replace everything in there. Polish the crank, install new bearings and thrust washers everywhere.

 

[rosefaj24]

Mazda parts yuo need

Hi there you need the ff Mazda Parts:

Valves
Valve springs
Timing belt
Balance shaft delete
intake
head studs
gaskets
clutch
Forged Piston

 

[RichB]

I agree with Maxx. I'd hate to throw a bearing after a rebuild knowing I could have put new ones in when the engine was already apart.

 

[Darth Vader]

If the motor's low mileage and been kept well, there's probably no issue with the main bearings. Turn the crank and test for tight spots and pull at least one cap and check on them, though. You don't need valve stem seals unless the motor was smoking at startup or on decel before you decided to rebuild it. You might want to pull an exhaust valve from #2 cylinder (likely hotter than the outers) and check for seat erosion or burning. Really look at the head gasket too, as it can indicate tuning issues by the condition of the fire ring.

I know it's common today to just shotgun blast everything and hope that you hit the part that actually has the problem but, I learned to not mess about with things more than you have to. This can lead to other problems and a compounded risk of installation errors.

 

[MSMS3]

I agree with everything Darth says with two additions. If you're going that deep into the engine, consider replacing the timing chain, and get a new oil pump. That's just good insurance against problems on down the road. I've seen too many performance or stock partial builds fail because of re-use of the old oil pump or because the engine jumped time due to a chain that "seemed" to be o.k.

Our family business is an automotive production and custom engine rebuilding company and machine shop. We also build race-prepped engines to their specs for teams and "speed shops." I grew up in that business and was active in it for many, many years, but ultimately pursued a different career (law). I do still maintain an ownership interest in the company and provide its legal advice and representation. Our company, like most in the business, flatly will not warranty the machine work or the internals sold for these type of partial rebuilds unless we have proof that a new oil pump was intalled and that the timing chain was replaced.