General Queries On Rebuilding Engines

[djinuk 2]

Just general questions really on engine rebuilds. The engine in question is a renault 5 gt turbo pushrod engine which is lacking oil pressure even after refurbing the pump. Now i have never rebuilt an engine however these seem fairly simple so im going to give it a go. My question is do you always replace the pistons/rings and liners, or is this subject to scoring of the liner after the engines been stripped down. And with regards to the crank and bearings, do you only have the crank reground if it shows scoring of the bearings. If not is it a case of simply remove and refit with new standard bearings. ? these may seem really simple questions but like i say its all new to me and all help is appreciated.

[richsmells 2]

Get the crank measured by an engine builder/machine shop. If it needs any machining, they should advise which bearings to use.

 

They may just polish it to tidy up the journals. Use some plasti-gauges when you're re-fitting the crank

[djinuk 2]

ah ok, so either way you say take the crank to a machine shop and see what they say as im guessing they can measure them all up etc. Ill need to get them to fit the pistons anyway as they are interference fit. Now i just need to see where the local machine shop is.

[djinuk 2]

oh furhter more whats plasti gauges and how are they used?

[Sandy 189]

It's a plastic thread that you place on the journal/bearing to dry assemble, so it crushes and indicates the clearance by how much it's crushed.

[djinuk 2]

ah that makes perfect sence, so ideally im guessing theres a clearance that id be trying to achieve and also the clearance should be the same across all 4 bearings.