Help Identifying Engine Wear

[nicr4wks]

Hi Guys,

I'm currently having my first go at building an engine, I'll be putting together a 25/30.

Today I pulled the girdle and pistons, and looking at the bearings/rings I'd say they've been done previously due to the fact they look in so much better condition than the rest of the engine, but since this is my first rodeo I'd like to confirm!

Judging by the way these components are worn, do you guys recommend I replace rings or any other components also? (I'm planning to do bearings).

Cheers!

Edited April 6, 2013 by nicr4wks

[blind_elk]

As a general rule, if you have the engine apart, then replace all the bearings and rings.

[89CAL]

as above

might get away with just honing the bores, to hard to give a definate answers from the photos

are those neo pistons or non turbo pistons? Mine didnt have valve reliefs, not sure if its a neo thing or non turbo thing

[StevenCJR31]

^^ do as these guys say, bearings and rings are cheap anyway

[StevenCJR31]

as above

might get away with just honing the bores, to hard to give a definate answers from the photos

are those neo pistons or non turbo pistons? Mine didnt have valve reliefs, not sure if its a neo thing or non turbo thing

id say they are stock rb30E pistons. . looking at the reliefs its almost like nissan wanted a twin cam 24 valve head on them from the start Edited April 6, 2013 by StevenCJR31

[nicr4wks]

id say they are stock rb30E pistons. . looking at the reliefs its almost like nissan wanted a twin cam 24 valve head on them from the start

Spot on. They are cheap so guess I'll just do the rings. The end bearings looked hardly used whereas the inner bearings had very obvious wear, I wasn't sure if this meant that perhaps some machine work is required for more even wear or maybe the girdle just wasn't torqued properly.

[89CAL]

Damn. Didn't ever see rb30 pistons when I had my VL. Even had a spare engine I ended up selling

[StevenCJR31]

^^ rb30engines are cheap enough. . sometimes cheap enough to come with a vl ! personally prefer to use R31 skyline bottom ends as they have 3 ribbed belts on the balancer unlike the vl which has 1 v belt and 2 ribbed belts

Edited April 7, 2013 by StevenCJR31

[MrStabby]

As a general rule, if you have the engine apart, then replace all the bearings and rings.

How important is it to rehone when replacing rings? Is it mandatory because the seal will be hopeless without a new ring to new hone bed in? Or can new rings bed in without a fresh hone?

[StevenCJR31]

for peace of mind a light hone is a good idea and is not overly expensive, removes any glaze that might be on the bore

[nicr4wks]

Cheers for the tips all.

How about where the rod connects to the piston, is there some sort of bearing here I should look at replacing?

[StevenCJR31]

there is a piston pin there that does wear out. . .all i can suggest is you take the lot to an engine reconditioner where they can run calipers over the worn/unworn parts and tell you if its still within tolerances and what parts you need to buy

[Josh.69]

Noob question, what does it mean when you 'hone' something?

[StevenCJR31]

Noob question, what does it mean when you 'hone' something?

google!