Log in

View Full Version : 3S-GTE engine making a knocking noise (bottom end failure?)



Jim-SR
30-10-2007, 19:13
this isnt strictly mk1.5 related, the engine is still in an ST205. but ive drawn the short straw at work and have to fix the sodding thing. absolute nightmare of a car to work on, so im going to try and figure out what could be wrong with it before i start stripping it to pieces

basically it dropped a valve a while ago, it was all repaired to a semi-ok standard just so that it ran alright, with the intention of the car getting sold. however it got driven again, and a few weeks later the turbo blew up because someone wound the boost up. a 2nd hand turbo got chucked on and the car ran fine again, until a couple more weeks later it was getting absolutely caned up a motorway, and developed a very disturbing knocking noise. it came back on a trailer, and hasnt been touched since

the knocking noise is dependant on the engine revs. you start the car up, you get this constant knocking noise, bang bang bang bang. it sounds like hitting the engine block with a hammer would sound, and about that loud!! its enough to make you absolutely cringe when you start the car, but it had to be started a handful of times to move it around, and frankly none of us cared if it made it worse lol. as the revs rise, the noise occurs more frequently

so based on that, im convinced its not the turbo, as that wouldnt spin up fast enough to rise and fall perfectly with engine revs. my first thoughts were that the 2nd hand turbo has shÃ*t itself, dumped a load of oil through the engine, its run low on oil, and has then done a bottom end bearing. it certainly sounds to me like a bottom end bearing has let go in a big way. but the oil level is perfect

you have to bear in mind here that when it was being driven the driver was in rush to get somewhere, and wouldnt have even blinked at the gauges showing up anything worrying, and even the noise probably started quiet and was driven until it was too loud to bear. i dont think the engine runs badly, at idle it is spot on aside from the knocking noise. so to me that would suggest it hasnt dropped another valve.

does anyone have any suggestions on things which can commonly go wrong on 3S-GTE's, as its not an engine i know particularly well. and basically, has anyone got any suggestions on what it could be, based on those symptoms?

i thought id ask here ahead of any of the Celica forums, etc, because i know that lots of you know these engines better than any of the Celica guys, and i know how helpful you all are ;)

so any help at all is greatly appreciated!! cheers
JIM

Paul Woods
30-10-2007, 19:18
sounds just like a bottom end to me...... the easy way is to drop the oil out and examine it for bronzy coloured shards

Jim-SR
30-10-2007, 20:15
if it were my car id do something cool with it, probably still sticking to the 3S-GTE though ;)

but its not, im just the unlucky one thats got to fix it. i thought bearings from the first second i heard it, and if you think it sounds like the same Paul then id say thats probably confirmation enough lol

first thing im going to do is drop the oil once i get it in the workshop later in the week, so that should give an indication as to whats up. its going to be an absolute pig of a job though. if only someone else was taking the engine out and putting it back, and all i had to do was rebuild the engine lol

tom1mr2
30-10-2007, 20:16
As above really bottom end that mate, did the same on mine which was good really as it gave me chance to put a v6 in :)

snowtigger
31-10-2007, 19:37
sound like a diesel only ten times worse or a very old cement mixer with a couple of bricks in it.i think your big hend has gone sir have fun.

Sports Toyota Breakers
01-11-2007, 10:46
If the noise is from the top end check that it's not just an exhaust manifold nut or two come loose. If the head & turbo has been replaced this would be where I'd start looking. The bottom end on the rev3 engine is bloody strong so it would have to be seriously abused to give up.

Jon

Jim-SR
01-11-2007, 19:17
its definitely not something external rattling. my thoughts were along the lines of bottom end/main bearing let go, or possibly a dropped valve. i wish it was as simple as a nut or 2 loose on the exhaust lol

looks like i wont have to deal with it for a little while yet, there are more broken cars to be dealt with first!

weegaz22
01-11-2007, 22:51
If the noise is from the top end check that it's not just an exhaust manifold nut or two come loose. If the head & turbo has been replaced this would be where I'd start looking. The bottom end on the rev3 engine is bloody strong so it would have to be seriously abused to give up.

Jon


doesnt need to be abused, all it takes is for oil pickup exposed to air under hard cornering/ low oil and that will prematurely wear out bearings

Sports Toyota Breakers
01-11-2007, 23:00
No shit :D

Marksman
01-11-2007, 23:08
No shit :D

You sound like a man speaking from recent experience?

Owen.

snowtigger
02-11-2007, 00:20
a baffled sump then would solve that problem surely some one has done this already.old mechanic dicktum engine oil cheap engine bearings expensive

Sports Toyota Breakers
02-11-2007, 09:33
The rev3 3SGTE sump is pretty good actually - of the dozens of people I know who regularly track their ST205, even with coilovers & semi-slicks, never has one had bottom end :gay: trouble - it's always ringlands.

Owen, I only speak from experience of owning/tuning/melting 4 of 'em, fixing a couple of dozen up for friends, and breaking half a dozen for parts :P

Jon