300tdi knocking noise

[orangeshannon]

hi i was looking at a disco with the 300tdi engine it had a knocking nosie from the bottom end but once reved up it went away and we noticed that the harmonic balancer was wobbling around do you recon that the woodworm key has flogged out and the harmonic balancer it jiggeling all around the place or could it be the balancer its self?

[uninformed]

could it be a big end starting to fail :confused:

[Pierre]

Take off the auxiliary drive belt and check the crank pulley for looseness. It may not be the keyway at fault, but the rubber insert between the pulley and the centre may have failed.

This has happened to a vehicle of ours recently.

Fix: replace the whole harmonic balancer/pulley assy.

HTH

Pete

[orangeshannon]

ok yeh i was thinking its got something to do with the harmonic balancer are is don't spin straight its all over the place i'm gonna have a look at it again this weekend hopefully its an easy fix

[rick130]

I'd tip the harmonic balancer too, and hopefully it's just started to separate and not loose on the crank.

[orangeshannon]

so with the harmonic balancers is it the bolt that normaly get loose on them i read on on of the other pages they come loose and people put a washer in there to stop it and just replace that woodworm key and it should fix it ay?

[rick130]

The rubber can separate and so the balancer needs replacing.

If it's come loose on the crank you need to really have a good look at the crank nose as it can stuff it badly.
That isn't good.

Oh, and BTW it's a woodruff key ;)

[orangeshannon]

haha i duno where im getting woodworm maybe thinking of something thats got nothing to do with engines at all haha sounds about right.

im going to be having another look at it this and see whats the go with it

[Pierre]

os, if the installation is done correctly according to the manual, it is extremely rare for the crank bolt to come loose. Be aware that you need to lock the crank in place to loosen the bolt - unless it's already loose!

There is quite a bit of info on this topic. Use the search function to your advantage.

Pete

[orangeshannon]

i had another look at it the other day pulled the fan off to gain be able to get to the balancer turns out snapped crank :(

[rick130]

Ouch.

That's exxy.

[orangeshannon]

yeh i had a look at prices the only one i got for now was around $850ish plus i would put all new bottom end bearings through it. you should of seen how much play that harmonic balancer had you could move it in and out, up, down, left and right by a couple of mm and you could see that big bolt to hold the balancer in place moving all around the joint as well which didnt seem to good would be great if it accually wasn't that. like if the bottom bolt was that loose that it could move around that much ahah that would make a dream come true

[uninformed]

what would cause the crank to snap?
what are the likely on flow damages?

[orangeshannon]

well im only just started my second year as diesel mechanice so im still only learing but i asked 2 of my traqdesmen today about it and they say no it can't be a snapped crank cause its still running which now thinking of that it does make alot of sence other wise it wouldnt run at all so i might have to pay them a slab to come up and have a look at it for me and so i can see what they recon it could be

[bee utey]

well im only just started my second year as diesel mechanice so im still only learing but i asked 2 of my traqdesmen today about it and they say no it can't be a snapped crank cause its still running which now thinking of that it does make alot of sence other wise it wouldnt run at all so i might have to pay them a slab to come up and have a look at it for me and so i can see what they recon it could be


My brother drove his 3.5 V8 RRC home for 30km with a snapped crank. It depends on where the break is and how fast you rev it.

[Pierre]

So, where do you think that it is broken? Does the pulley and crank nose move together? When you turn the crank bolt, does the pulley move in the same plane? If the crank is broken, chances are that the break will be between front and second main bearing.

Good luck.

[orangeshannon]

yeh i got told if its cracked they crack between the two main bearings in the front but the guys from work seem to think tat its not that cause thats sorta where the timeing belt would be and it wouldnt be in time ect but the thing ru soo smoothly we took it for a test run the first day i sore it and we would of been doing about 120k down hill so it was revving up there and was only knocking on idle if u reved up anything even off a slight idle the knock went away

[Judo]

This is a complete stab in the dark, but are valve clearances a possibility?

[Pierre]

So is the outside of the balancer (the bit with the grooves in it) moving relative to the centre of the balancer (the bit with the bolt through it)? It sounds like the pulley has delaminated.

Check it carefully.

Pete

[orangeshannon]

yeh the guys from work seem to think its not the crank still but could be the balancer flogged out abit well enough for it to be able to move around that much which i dont see why the bottom pullt bolt moves around with it unless thats loose to?

[orangeshannon]

well i got some good news i pulled the harmonic balancer off to find that its in good condition and the center of its not worn or the crankshafts not worn aswell. so i took the timing belt cover off and the shaft is still moving around but its not all that bad. its like when your wheel bearing are flogged and your wheels has a little up, down, left, right move ment in not to worried about the in and out movement its only about a mill so not i gotta take the engine out and drop the sump off im sooo hoping that its bearings or something easy like that to fit wrong with it.

wish me luck, oh and by the way i gotta get it running and re-regiested befor easter or i'll just be staying home and not camping :(

[bee utey]

Compare the movement at the front of the crank with the rear by looking at the flywheel at the same time. If there's relative movement then its still likely to be a broken crank. There's bound to be a good crank available somewhere as all these heads have failed lately...

[orangeshannon]

well i found out on the weekend bad news it was turns out my crank is snapped

[isuzurover]

well i found out on the weekend bad news it was turns out my crank is snapped

Ouch. So what did the tradies at work say when you told them they were wrong?

Btw:
http://www.paddockspares.com/err2112-crankshaft-300tdi.html

[orangeshannon]

cheers mate i found another site slightly cheaper its rimmerbros.

yeh i told the guys at work about it and there like F*&KING HELL!!! haha.

i would really like to know how it accually snapped when i take it out the engine i'll put some better pics of the snap up :D yay $1,000+ later haha

[uninformed]

so since you are pulling the crank, what are your plans/ what parts are you going to replace and how much of a rebuild are you going to do?

[orangeshannon]

ok what im going to do because of my situation im going to replace every bearing in the bottom end even if there in good nic because i figure if i buying the crank alone for around about $800 aussie dollars im going to spend the money on it and do it properly by getting all new brearings, seals and gaskets. i'm thinking that its going to cost me around $1,200ish but i'm also going to flush the engine out with some kerro and put some parts through the parts wash at work to make sure that any metal that is floating around is gone. im not going to worry about doing pistons and rings as there fine and not smoking i was thinking about doing the head gasket and replacing all gaskets but theres no oil leaks so im not going to bother with it. bit its also gave me a chance to clean the intercooler which was about 90% full of mud and we found a crack around the front drivers side body mount in the engine bay which im going to weld up. i also cleaned the whole engine bay and its spotless no more mud :D can't wait to get it on the road and take out bush for my first time in it

[orangeshannon]

i just ordered all my parts im getting brand new crank, bearings, seals, gaskets, top and bottom radiator hoses, and a few other bits and peices and postage for change from $1,200 :D now thats not a to bad buy considering the cheapest crank i could get here was $1,050 and the bearings where $240 for the set

[Pierre]

While you've got it in bits, do the timing belt/idler/crank sprocket as well.

Pete

[orangeshannon]

yeh mate im doing everything as i don't know how many k's since last belt ect just in case and is alot easier to work on when out of car to and its in bits so you would be stupid not to