Big End

[insanity007]

Hi guys,

I've got a knock coming from the engine that's pretty loud on startup but it goes away when it's warmed up. My mechanic reckons it's the big end. How much would this cost to get fixed?

I've got a 1997 WRX Sti Wagon

[nt_a_foz]

Have a search man,

this has been covered hundereds of times..

Youve got a few options

A/2nd Hand motor

B/Brand new v7 sti short block and bits and pieces

C/Forged ground up rebuild

All depends on your plans for your car, budget and timeframe...

Have a search and see what yo ucan find

[Shale]

Bigends don't go away when warm, surely. Lifters, piston slap?

But yeah, best to have a search OP - plenty on the subject around.

[nt_a_foz]

Yeah reading your original post if it goes away when warm itd be more liekly to be pistion slap id say..

Big end will still be roudy when warm

[Treecrusher]

A big end failure will get louder under load, whether the engine is warm or not. Piston slap will be loudest when the engine is cold, will be quieter when warm and you will be able to make it louder by lifting engi e revs a little over idle (I.e 0 manifold pressure)

[Pappu1]

yea not likely big-end as it gets nosier as revs rise and dosent matter hot or cold

[wrx_lou]

Yeah, sounds like your mechanics a doosh. Get a second oppinion.

[Swindog]

piston slap will disappear above certain revs depending on type. Mine sounds like a tractor at idle but sweet as once bring revs up.

Id be checking for sticking valve or sumsuch

[Treecrusher]

The other thing you can do is get a couple of long extensions (from a socket set) connect them together put one end up against your ear and place the other end on different areas of your block, while the engine is running. It works kind of like a stethoscope and you will be able to pin point exactly where the knocking is coming from.

If it is the bottom end the knocking will be really loud in your ear when you place it somewhere on the middle of the block, piston slap will be loud on one of the cylinders (rear drivers cylinder seems to be a regular one) and something wrong with the valve train will be loud on the heads or valve covers.

A done bottom end will be obvious.

[Swindog]

Done this with a long screw driver with a metal end on the handle.

[Guest SPANKU]

could be the heads, i had this same problem with my other motor awhile back ages a go. turns out that the shims needed to be reset.

[Pappu1]

 Treecrusher said:

The other thing you can do is get a couple of long extensions (from a socket set) connect them together put one end up against your ear and place the other end on different areas of your block, while the engine is running. It works kind of like a stethoscope and you will be able to pin point exactly where the knocking is coming from.

If it is the bottom end the knocking will be really loud in your ear when you place it somewhere on the middle of the block, piston slap will be loud on one of the cylinders (rear drivers cylinder seems to be a regular one) and something wrong with the valve train will be loud on the heads or valve covers.

A done bottom end will be obvious.

good suggestion ,!

[Guest]

check for metal in the oil

[Stoffa]

water pump on the way out will also causing knocking that goes away when warm

[insanity007]

hmm...either way I'm not sure and I don't want the engine to blow up in my face so where's a good place I can take it to on the shore or close to the shore to get it checked out to find out exactly what the noise is and how I can fix it?

[Treecrusher]

 insanity007 said:

hmm...either way I'm not sure and I don't want the engine to blow up in my face so where's a good place I can take it to on the shore or close to the shore to get it checked out to find out exactly what the noise is and how I can fix it?

This is only my opinion, so take it or leave it. But I think you are better off diagnosing it (either yourself or another fellow clubsub member) and then ring around asking for quotes. Once you find a good price tow or tailor your car to prevent further damage. That way you can get several prices and aren't at the mercy of the first shop you get to.

[Shale]

Don't bother with the Shore. Go to Highbrook. Go directly to Highbrook Automotive. Do not pass Go, do not collect $200.

[Guest]

Go to Northern Car Services in Glenfield?

[insanity007]

What sort of Turbo's do these engines come with? Once I get the engine fixed what's a safe boost to run? I was running 15psi on my '93 WRX without any worries with the standard turbo on that.

[kingersman]

a v1 wrx i believe is the td04 but sti is td05?

and its like 12psi or something like that standard

[WRXER]

td05 on v1's too , the hatchs came with the td04's on the v1/2 models.

[insanity007]

What sort of boost can these run safely?

[WRXER]

More boost then the stock engine can handle , unless I've missed something do we definitely know what turbo you have at the moment ie is it a vf23,24 etc

[Guest]

Don't go to Northern Car Services, they hav'nt been the best since those asians took over.

Take my advise and take it to Engine Specialties on Hillside Rd Glenfield and ask for Dave, hes really good and will tell you exactly whats going on, be prepared tho he tells you how it is!

http://www.enginespecialties.co.nz/

or if you're around the Torbay area i can come over and have a listen, i'v been there and done that.