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Can anyone shed any light on this? Was checking my timing this evening. Car runs quite well, maybe a little sluggish and smells of unburnt fuel a bit.
Anyway if the timing marks on the case are at say 1oclock. My mark on the crank pulley is at about 10 o clock. Massively wrong.
Am I reading it right? Could the timing be out by this much?
Any ideas greatly appreciated!

It could be a worn crankshaft keyway and/or an incorrectly set CAS. Which model car?

If you havent clipped the timing light onto the wrong lead, my bets on the crank pulley, it may have slipped between the pulley and the rubber dampener. So your timing may be right but your mark on the pulley has moved.

If its running anything close to right than this 30 odd degrees out is wrong. It simply cant be that far out and run ok.

Dann

Thanks for the input. Engine is a long nose 1.6 and it does run Ok. Just giving it a tune up.
I guess I need to check tdc with a dip stick in no1. At that point should the pully mark line up with the tdc mark on the belt cover or point straight up?

Tdc mark. If it doesnt then either the timing belt has slipped 8 teeth (it obviously hasnt) or the harmonic balancer has slipped on the press fit rubber.

Dann

Thanks dan, if it's the harmonic balancer then I need a new pully?

Id suggest it.

Dann

Mxbob wrote:..Car runs quite well, maybe a little sluggish and smells of unburnt fuel a bit...

These terms are mutually exclusive. I wouldn't be surprised if you have a serious timing problem.

30 degrees advanced, yet it still runs at all....?

Doubt it.

Dann

Ok, checked the pulley marks by finding tdc with the dip stick in no1 cylinder.
Crudely marked the pulley with a new mark. Checked the timing and the new mark is showing about 18 degrees! Had it at 7k rpm earlier today .
The Cas was advanced about as far as it will go. I retarded the timing by about 5mm rotation of the Cas to put the timing at a more 'standard' setting. Will need a new pulley to get it spot on though as I know the dipstick measurement is not the most accurate.
Ho hum

The dipstick method is accurate to a degree or 2.

So your saying that at TDC the marks show up at 18 degrees advanced? It should be at 0 degrees spot on. So your balancer has moved if thats the case.

Its will NOT affect performance at all. But its dubious over the long haul to leave it, and makes setting timing hard.

Dann

Kinda obvious question but you're setting to locked 10 degrees in the diag box if on stock ECU?

It was showing 3 hours advanced (thats 30 degrees). The stock ecu NEVER goes past 33* at any point. It wouldnt matter if it was locked

Dann

I'm a bit lost with the last couple of coments.
With everything as it was, I checked the timing and it looked about 30-40 degrees advanced.
I've since made a new TDC mark on the pully using the dip stick method.
I then warmed the engine, bridged the diag contacts, set the idle. Then checked the timing again and the new pully mark was showing at about 18 degrees.
I turned the cas about 5mm to get the timing back to around 12 degreed +/- 2 degrees and adjusted the idle to suit.
I thought bad things happen after 14 degrees?

detonation CAN happen. And 14 degrees is the internets universally accepted safe limit.

Id say youll be ok. The sluggishness is probably due to detonation though. Ita not good, but its still running so you mustnt have done too much damage.

Obviously the slipped pulley hasnt affected the timing, that must have been a stupid PO or something.

Dann