Engine swap, motor clanging... Where did it go wrong? Stuffed piston?

[CHA53R]

hi there, i baught a vn series 2 donor car for my vr commodore, motor was quiet and ran great in the vn.. found out that didnt work in my vr so had timing cover camset and timing chain changed to make it work in my series 2 vr as it has a cam sensor... my transmission is on the way out but left it in as the motor change cost me $950 2 motors out 1 put in and parts change over. picked it up yesterday. had start up problems thought ok needs new plugs and leads. drove it 35kms home.. had a play on the highway to see how it went and ran good.. 160kms no probs... went to take it out today and theres clanging coming from the motor at the back, could it be the transmission at all or a stuffed piston? how would it run if it is a stuffed piston? or could it be a bearing problem? any insight? cheers..

[Brett_jjj]

It might be something simple like a faulty starter not retracting away from the flex plate.Id start by looking at it.There will be some sort of marks on it if thats the cause.

[hako]

I'd agree with Brett that it sounds like the starter/ring gear. Also maybe the exhaust manifold loose/hitting body. Why not take it back to where you got it fixed up at.

[CHA53R]

i did, he reckons the flex plate and everything are tight as. and doesnt have a clue what it is.. he said maybe piston.. mind you he's a inbred looking backyard wrecker... lol i thought if it was a piston it would drive like crap. but drives better than my old engine when it was running good... also has some sort of ignition problem as the idle is up and down and screetches sometimes too when you turn the key to start it, like when you turn the key when the motor runs and you turn the key the wrong way and it goes rrrrrrrrrrrrrrt lol i changed the plugs to the ones off my old motor which are only 1000km old and didnt make much difference. also noticed park doesnt lock straight away rolls a little bit then clunk locks in. my transmission is stuffed but not that stuffed... and at around 100kms it sort of stumbles along when you put the foot down on it drives good but... so not sure if its the tranny doing it... either he has stuffed something up or iv swapped a dud for a dud in the way of motors... motor ran perfect when it was in the vn but..

[db_notso]

+1 loose flex plate to tourque converter bolts
makes loud metal clang noise when on off acceleration
tghiten those buggers up

screeching noise could be loose flex plate to crank bolts.. (box out)
or loose starter motor
or starter different size teeth? not sure if they changed flex plate at all in models
or damaged ringear or starter teeth

if motor ran good before then something hasnt been fitted correctly

check engine earth is tight as well as some basics like battery terminals etc before going too crazy

[CHA53R]

its not noticable while driving its more on idle and when the revs are low.. sort of sounds like an old diesel engine....

[db_notso]

okay then
start engine
disconnect injectors one at a time and see if knock goes away
(plug back in then check next one)
when you find out which cylinders are KNOCKING you know the fault is in that cylinder or its system parts

if all are the same could be an oil pressure issue
do an oil pressure test

e.g. check plug tight in hole, next for me would be a compression
1st: check dry cylinder
2nd: next one with a few ml of oil in there (wet test) this may help you figure out if its a valve problem or a piston to bore problem

if compression is good and no fault found but noise goes away when undoing injector
likely to be a problem with piston to pin or rod to crank clearance like a spun bearing
you would be unlucky for this to happen but better to know then not

NOTE: taking the injector off removes the compression preasure from that cylinder another way is to remove plug lead
anything to stop combustion on one cylinder at a time but i like injectors as no sparkie sparkie ow ow

[pjdm1980]

If it didn't do it in the other car then it's bound to be a fitting problem and from the sounds your describing it's a starter or loose flywheel, good luck.

[MR.HG]

aww man that sux..... is this 'mechanic' guy a friend or friend of the family etc? ( i assume he isnt family cos you referred to him as inbred ) i love it when they try to palm it off as something that makes it hard to check......did he even go over it again for you? put it up on the hoist? or just talk bullshit to you and ask you put your bonnet up while he listens with a puzzled look on his face? fvckin cowboys man, ruin the trade for everyone else...im sure you did your job properly to earn the money to pay him to begin with.....you would think he would do the right thing to earn his money but unfortunately this is not the case......situations like this make me mad mate i hope you get to the bottom of it

[James39]

Mine ran like that, but went away after the second oil change.. I do suggest replaceing your starter motor as sounds like it could be on it's way out.....

[CHA53R]

hes a wrecker in the paper... he looked under the bonnet with a puzzled look, i took the car to a mechanic today and 2 mechanics checked it out.. they said doesnt seem to be pistons or anything, they said sounds like loose flex plate as you guys said.. rang the guy that did the motor swap and he swears blind its not that and the 2 mechanics are morons lol said he will have a look at the flex plate, to leave the car with him but if its not that he will charge me... ended up just saying ok mate il check it on the weekend.. if it turns out its loose and has stuffed anything im going to go over there and get my money back... im sure he will learn next time,when i drag his arse to the ATM to get it back.. happened a week before chistmas my holidays from work were spent sitting at home waiting for the stupid thing to be fixed and handed over almost $1000 plus had to put up with the missus winging at me the whole time...

[justbad4you]

hope it all works out for you mate>? not a good start to 2011

hes a wrecker in the paper... he looked under the bonnet with a puzzled look, i took the car to a mechanic today and 2 mechanics checked it out.. they said doesnt seem to be pistons or anything, they said sounds like loose flex plate as you guys said.. rang the guy that did the motor swap and he swears blind its not that and the 2 mechanics are morons lol said he will have a look at the flex plate, to leave the car with him but if its not that he will charge me... ended up just saying ok mate il check it on the weekend.. if it turns out its loose and has stuffed anything im going to go over there and get my money back... im sure he will learn next time,when i drag his arse to the ATM to get it back.. happened a week before chistmas my holidays from work were spent sitting at home waiting for the stupid thing to be fixed and handed over almost $1000 plus had to put up with the missus winging at me the whole time...

[CHA53R]

ok,to start off brake pedal has gone hard like my booster has gone, but there is no whoosing sound... the booster was replaced 2 months ago with a new one.. any ideas? lifted the car up, got under, 2 nuts missing under steering collumn on the inspection plate... took off the y pipe, undid the steering. noticed bolt from trans to engine bottom left loose as, next bolt up missing. took the starter off and the inspection plate... flex plate was tight. torque converter to flex tight. but the teeth on the flexplate are chewed on edged in spots.... went got starter off my old motor and put that in bolted up the y pipe and started it... still ignition problems... still the rattle was idling high so took the vacume hose off the booster and got the missus to put her finger over it while i was unger the car... noise is coming from in there somewhere at the back any ideas.. checked the oil too and seems real thin... might drain it and put a thicker oil in incase its piston slap. its louder when you listen to it from under the bonnet but there coming from the back area where the transmission bolts up... any ideas on what to do?

[Matty.b]

take photos of anything you find or even better yet video footage in-order to come back at the inbred if you need to

[Blakvsexec]

This is the reason i NEVER let anyone else touch my vehicles.

[CHA53R]

i have been, i usually do it myself to, just didnt want to do the change over on timing cover,timing chain and camset when he said he can do it all cheap i went for it.think i might get the mechanic down the road to come look at it now its all open... radiators leaking and alternators squeeling, so might change alternators today and chuck some stop leak in it.

[CHA53R]

ok did up the y pipe properly so all is quiet, cant hear the noise at start, but got it doing it again, flexplate has a slight wobble and that sound is either in the plate or the torque converter.... all bolts are tight as but thats where the noise is... any ideas?

[pjdm1980]

Did you change the flex plate when you got the new motor if so did you use new bolts as those bolt are onetime use bolts only, they might have snapped if used twice?

[CHA53R]

nah was the same flexplate that was on it... thanks for telling me that im going to change flexplates to the one off my blown motor would have put the bolts in lol

[db_notso]

fyi - flexplate should not have a wobble in it, should spin perfect inline with motor
likely he jammed motor in with flexplate on and bent it = gearbox out!~

[CHA53R]

looks like it, doing it on the weekend.. sounds like a good day to have a few beers aswell... i reckon he dropped the motor in on the torque converter and bent and cracked it..

[db_notso]

looks like it, doing it on the weekend.. sounds like a good day to have a few beers aswell... i reckon he dropped the motor in on the torque converter and bent and cracked it..

flex plate bends and even cracks under high powered situations.
check he hasnt damaged something and its jambed up in the housing while your there (just in case dont forget you may want to replace tourque converter seal while your there... and or rear main...

[CHA53R]

i got the mechanic down the road to come up for a 6 pack and he didnt even start it... crank bolt is loose... hes coming up tomorrow to tightn it.. hopefully that fixes the problem..

[db_notso]

yeah that would be a pretty bad noise if loose
let us know how you go~!

[CHA53R]

ok that didnt work either... they going to come back again tomorrow