re-using bolts in engine rebuild

[Pube]

Can/should I re-use old nuts and bolts when rebuilding my 1G. Bolts of concern are mainly connecting rod nuts and bolts, head bolts etc. Considering the engine is having its first rebuild and the threads are not damaged, are they ok to use again?

[feral4mr2]

i've re-used all the bolts in my 4ag/gze/gte variant re-builds with no hassles.

though for peice of mind a new set of head bolts from toyota are prity cheap.

[IN 05 NT]

yeah re-using the bolts will be fine, just aslong as they are toqued to specs.

some cars you do have to replace bolts, such as falcon head bolts due to stretching,

blake

[timbosaurus]

I'm no "stick to what the books says" kinda guy, but all my rebuilds have used the old bolts, and mine haven't failed.

I can't talk for highly stressed engines, or 1G's in particular. But for regular factory rebuilds I'd be happy re-using the old ones

[EVOSTi]

you can reuse your big end and main bolts no trouble, head bolts can be reused as long as they are not torque to yield. you'll know if they are torque to yield if the torque settings have 'angle' settings after the Nm settings. having said that i have reused torque to yield bolts on old shitters no trouble as long as you keep in mind they have been stretched already.

[jimmmayyy]

Probably wouldn't want to reuse conrod bolts however!

[merc-blue]

Rods and mains yes. head no.
For not alot of money its not worth the hassle og having the head lift abit. your headgasket probly cost more than the bolts will

[EVOSTi]

Probably wouldn't want to reuse conrod bolts however!

whys that? ive never replaced conrod bolts.

[jimmmayyy]

Well they are probably one of the most stressed bolts in an engine, especially with high rpm.. Constant thermal loading and massive rotational forces etc. Of course they will probably be fine, but personally i wouldn't re-use them,. but it's all up to Pube in the end.

1G head bolts would proabably be only about 10 bucks each, rod bolts probably only 5-6 bucks. Cheap insurance in my opinion. How concerned about reliablity are you? You wouldn't want them to fail after just rebuilding it.

[EVOSTi]

spose, im talking in general about engines, not specifically 'performance' engines. but i still wouldnt be too stressed about it, how often do you hear about big end bolts failing? i guess it depends how much of a rebuild you are doing. if youre getting new rings, bearings, head gasket etc basically a freshen up, i wouldnt bother. if youre going new pistons and the rest then an extra $100 or so isnt gonna seem as much.

[jimmmayyy]

Yeah i know what your saying, I have done it before on shitters. 1G's being a fairly revvy engine, and going by his avatar it's probably gonna cop a hiding I personally wouldn't risk. It all boils down to budget and/or personal choice really.

[MRMOPARMAN]

im with jimmy, id never reuse rodbolts on a performance engine. cheap shitter ill reuse everything providing its not stuffed. but in something that i care about, rods definately, head bolts probably too.

[Billzilla]

im with jimmy, id never reuse rodbolts on a performance engine. cheap shitter ill reuse everything providing its not stuffed. but in something that i care about, rods definately, head bolts probably too.

Quite true.
You're asking for trouble if you re-use rod bolts in pretty much any engine, especially a higher performance one.

[30psi 4agte]

So in saying that /\/\/\/\ Does that mean you fit new bolts every time you pull the engine down , even if you replaced them last rebuild ?? --- I would think not.( you might though bill with you pilots wage )

I replaced my rod bolts not long ago and have pulled the motor down twice now without seeing any need for replacement.

As a rough rule : If you know of the bolts origin IE You know how long it has been in the engine ,the stresses it has seen and the reason the engine is being pulled down ( spun bearing or just a freshen up) you will beable to make a educated decision if it is ok..

It is when you dont know of a bolts origin that it is a guessing game. If you plan to make some decent HP then i would suggest replacement of the bolts. If it is just a stocker than you "should" be ok.

If i remember correctly..... You can get measurements of the std bolt length and measure them to see how far they have streched..

Im sure the 4age has a max limit for rod bolt stretch to check for. So id assume the 1G is the same.

[Talasas]

you'll know if they are torque to yield if the torque settings have 'angle' settings after the Nm settings.

4AGE head bolts aren't torque-to-yield and they are specified in angles after the first torque spec.