3SGTE rattly on low revs + when cold only ** problem found **

[thechuckster]

mine was down to the copper ... crank was ok.

[Aust162]

no: 4 went on my 3SGTE. are you planning on changing all the bigends rob?

[RobST162]

hey aust, well here's what I'm thinking

1. Remove all the big ends and inspect crank.
2. (hopefully) Replace all the big ends
3. Use a 20/50 oil, and try and get my hands on an oil pressure gauge and see what kind of pressure I get
4. If it's good enough, I'll use the car.

I'd almost prefer not to look at the mains in case something is up there, because if they're stuffed, i'm stuffed.

[thechuckster]

Rob, if the big ends have been flogged out like that example, you'll probably find mains in similar condition?

did you check the specs on the oil pump (rotor to case clearance and rotor to stator)? mine was in serviceable limits but other stuff (blocked oil cooler, no thermostat, use of chemiweld, poor maintenance etc) conspired to probably kill the bearings

It won't cost much more to buy some more bearings ... i guess you're trying to avoid removing the motor?

[RobST162]

i really needed to take the car to melbourne this coming week

i've just had the engine out a few weeks ago, and can't afford a rebuild right now

if I can coax another 12 months out of it with some new bearings I can change while leaving the engine in i'd be just so relieved

edit: otherwise I'd never consider just changing big ends.. it's against all my best impulses, but really, if I put the bearings in, and then in 12 months or 6 everything just craps itself and I have to rebuild the motor totally, will I be in a worse position than I am now? no. all the same procedures will be followed and i'll be 'out of pocket' for a set of bigends, some sump silicon and 3.8l of oil

[neal]

Rob: what makes you think the bearings will crap itself in 6-12 months?

[Joshstix]

Because they have failed once and if just replacing hte bearings then it's treatng them like a service component rather than resolving the underlying cause for the failure. Unless of course the failure was caused by the dodgy oil pump.

[thechuckster]

rob: if you just do the big ends, then double-check the cooling system and in particular the donut cooler (for coolant flow).

personally, i think you'll find the trip rather harrowing as any new engine sound or slight shift in temps or the oil light flickering or taking an extra 0.5 second to go out on startup or etc... is going to frighten/distract you and your attention is going to be focussed somewhere other than the road?

[RobST162]

yeah good calls guys

the cooling system is pretty tight from all I can tell, the reason I put a limited lifespan on them, is if the mains are a bit worn, then pressure maintenance could be an issue.. increased wear.. not sure

but basically like josh said, but it COULD have been the oil pump, but then, I don't have much hope for the mains

rob

[Aust162]

My rod bearing went because of the age of my motor (imported with x many kms and probably zero maintainance) and i let the oil level go a bit low. Then had the car on the dyno and bam! so a combination of things.oil pump was checked and reused with my rebuilt motor. So rob, they might just be worn from age? or something is wrong with your pump.

[Moppitt]

Rob, if it does end up being big-ends and they haven't scored 'that badly' or are visbly ok, you can replace just that bearing in car with the sump off. im not a fan of it but i had to dono1 main bearing on a 40,000km old 320cdi benz the other day. And guess what, factory fix is this way. So if the best manufacturer of vehicles in the world says its ok, i dont see why not

There was a recall on e46 M3's (due to out of spec bearing shells that had us do the same thing, the S54 isnt just any engine either. That was as a preventative measure though rather than a repair so its a little different to your situation...

[sw20r]

I wonder if this might have had anything to do with it

This is what happened to my 3s a few months ago.. No thermo stat + loosing oil down to the last litre caused one of my bearings to go.. ended up costing $1300 to fix

items needed - crank resurface for insurance, replaced acl bearings with denso items and sleeves (to tighten piston to bore clearance as i had blow by)