<!-- from fixya rte -->Refitting a complete head - 2000 Mazda B-Series

If you are asking if you must use new head bolts, the answer is yes. The head bolts are designed to stretch a certain amount to help in clamping the head to the cylinder block. This stretch can only happen once. The bolts must be replaced with new ones.

Most likely a valve timing issue unless the plug wires are fitted wrongly and if it is a valve timing problem and a high performance engine or a twin cam there could have been some piston/valve contact.

It is best practice to turn the crank back a quarter-turn before refitting the cylinder head - a step many have forgotten to their cost. If the cam(s) aren't timed and the piston at tdc there can be valve damage when the head is refitted.

I suggest you recheck the valve timing and correct it if necessary and then carry out a compression test, check the firing order is correct, etc., etc.

have a compression test done as there may be bent valves from refitting the head and cam shaft/s incorrectly

I hope you realize now that slapping a set of rod bearings into an engine fixes nothing. Nothing short of a complete rebuild will resolve your issues. Everything has to be measured and refitted. The block, crank and heads will have wear that needs to be dealt with.

This is the wrong category for this problem.

Not really if the bolts are ok and the thread is fine and not damaged.

If engine will not turn over after head refit,make sure all timing marks are aligned when timing belt was refitted.If it will not turn over using socket/spanner on crank ,then thats the problem.

Hi this sounds very messy if somebody has made a mess of things the only way to check it out is to get it to a reputable garage and get it checked over ,did you have the head pressure tested as a common fault with these cars is internal cracking of the head which can often look like a head gasket failure the only solution then is a complete new head good luck with this

Did you get the torque yet?

Cheers