bad vibrations...... and no TDC mark on flywheel...

[Hiho]

Hello,

my recently installed 1.6TD motor is shaking/vibrating badly when idling and at low speeds. It was ok in the previous car, and ok up until I adjusted the timing belt tension (it was really loose!). Now it is a bit harder to start and shakes like mad until im cruising at 100kms/hr+ when it seems okay again. I have adjusted the idle upwards to 1000rpm but this has not made much difference.

Another issue is that there is no timing mark on the flywheel.... I will have to determine TDC somehow. Any suggestions?

Thanks!

Matt

[CRSMP5]

did you loosen the cam gear when you touched the belt??? stop right now..

you cannot just "tension" the timming belt on a diesel.. there is enough movement to throw off pump timming AND cam timming..

so do proper retime and tension of belt..

if belt was that loose.. do whole belt job.. also belt too tight will ruin fuel pump..

all factory flywheels have tdc marks too... may be rusty.. but its there.. usually by one of the flywheel bolts too..

[southernman]

It definitely sounds like the timing is off, and hopefully, that's all that's wrong.

On the timing marks; one of the things I did when I rebuilt my 1.6dsl was to visually reference the front of the crankshaft to determine TDC. It turns out the keyway on the front of my crank was indexed - exactly - to the timing mark on my flywheel, and moving the crankshaft so the keyway is located at 12:0-clock (pointing at the center of the camshaft brgs/cylinder head).

I realize you don't have the front pulley "off", but if all else fails, it will get you very close to TDC; then you can slightly rotate the engine to find the timing mark on the flywheel and reinstall the pulley.

I hope this helps.

Southernman

[R.O.R-2.0]

every time you take the crank sprocket off, you are supposed to replace ($$$) the stretch bolt holding the sprocket to the crank.

[rallydiesel]

Only accurate way to determine TDC is to take the head off and use a dial gauge. Find where #1 piston stops moving up from both directions, mark these on the flywheel lightly and then make a heavy mark with a punch/chisel exactly in the middle of them.

I have tried using a dial gauge through the injector hole and it was not accurate enough due to the deflection of the dial gauge shaft since the injector hole is at an angle.

Using the keyway as a reference is nowhere near accurate enough.

[gldgti]

hiho,

FYI - the crank sproket bolt is AUD$6.90 from VW.

Are you using a petrol cordoba flywheel? They do have a TDC mark but its pretty small - its like a little tiny dimple. Look for the petrol timing mark on the flywheel and the TDC mark is a lit smaller and about 8 degrees away from it.

[R.O.R-2.0]

hiho,

FYI - the crank sproket bolt is AUD$6.90 from VW.

Are you using a petrol cordoba flywheel? They do have a TDC mark but its pretty small - its like a little tiny dimple. Look for the petrol timing mark on the flywheel and the TDC mark is a lit smaller and about 8 degrees away from it.

how come everyone else is charging an arm and a leg for the same stretch bolt then?

[gldgti]

dealer prices are arbitrary....

big end bolts for my 1Y cost $9.66 each!

[Hiho]

Thanks guys.

Before i did anything i marked the flywheel based on the position of the cam, then tightened the belt then reset the cam to the mark on the flywheel. I made no adjustment to the IP though. I also removed the intermediate shaft to check the condition of the front bearing. It was fine. I may have not realigned the motor in its mounts when i finished this job, that could be causing the vibration. Like I said, it gets better at medium revs and light load, ie, cruising at speed.

I dont know what flywheel is in there but i couldnt see a mark. I will have another look in the morning. I will be replacing the clutch/flywheel and gearbox so i will be able to address all of this then.....

[Hiho]

one possible way to determine tdc with the head on would be to remove the cam, remove a follower, collets and springs from one valve allowing it to rest on the piston crown, pop a dial indicator on the top of the valve stem and viola! One would want to be careful not to rotate the crank too far as the valve may end up in the cylinder.

Works in theory, has anyone actually done this?

[gldgti]

should work. same as you would if the head was off though - measure 2 identical 'depths' either side of TDC and put your TDC mark in the middle.

use the intake valve as the guides are usually less worn than the exhaust.

I made a simple tool for compressing the valve springs thats pretty much just a peice of 50x5mm flat bar, bent with a 90 degree bend at one end thats about 3" long. theres a 10mm hole about 1" in from the end of the short leg, and another 8mm hole about 1.5" in from the first hole. you attach the end hole to one of the camshaft studs , and i have a piece of 25x25x3mm angle that keys into the 8mm hole. the angle bears on the spring retainer, and you simply pull the long arm of the l shape down to compress the retainer and remove the collets.

its a little tricky to use but it only took me 10 mins with a vice, drill and angle grinder to make it, and it works.

[AudiVWguy]

Try this

http://www.vwdiesel.net/forum/index.php?topic=25013.0

[CRSMP5]

pump timming will make it run and vibrate like hell.. need to check that...

[nathan_b]

Went to craftsman to swap out a bunch of broken tools this weekend, and they had an "over head valve spring compressor" for 19 bucks. Lifetime waranty. Works on our 8v heads and is adjustable to do others as well. pretty much impossible to beat.

[gldgti]

someone on this forum made a fantastic one quite a while back... might be in the FAQ sections somewhere - but  it was the rolls royce - I nearly bought one (I found one at an auto parts store here in australia for $70), but for that money it wasnt worth the infrequent use.