Technical 1.2 8v Timing marks, in a quandry

[KwikPhix328]

Hello folks,

Well I've been taking this job nice and steady, mostly due to the weather up here over the last few days.
I've had my head skimmed, (they only had to remove 0.008" thou'), I've got my new gasket set and new bolts. I also bought a valve spring compressor and stuff to give the valves a quick grind. all for a total outlay of just £90, probably nearer £100 after a bit of driving around, so far- so good.

Now the crux of this post.

I've had a good study of Dave's photos and also x-refered to both the Haynes manual and the Fiat workshop manual. I originally set my Crank timing mark at what i thought was TDC , (which looks like the apex of the oil pump web from all the pictures), the problem that i have though is that I have also borrowed a Dial Test Indicator from work and set it up on the main block whilst the head is removed. According to the DTI when my Piston crown is at the height of its travel up the cylinder (i.e. TDC) the crank shaft timing mark doesn't line up with any marks, notches , or reference points on the Oil pump web. If i then continue to turn the crank to line up the crank mark with the reference point on the oil pump web, ( at the apex??) the piston has passed TDC and is starting to go back down again on the 'bang' stroke.

I marked up the belt and pulleys and have transferred the markings over to my new belt, so I'm confident that I can re-fit the new belt in exactly the same position as the old one, i'm just not convinced now that the old belt was fitted correctly in the first place.
The fuel economy, etc , of the car Pre-blown head gasket was really very good, although i always thought that the idle was a bit lumpy. The emmisions where perfect on a recent MOT too, shall i just re-fit everything as it was ?

A picture paints a thousand words so here are some photos:
http://imageevent.com/sidandcoke/gashcarstuffhosting

Any words of wisdom greatly appreciated.

 

[teulk]

yeah its the "apex" you show in picture 7, that is the correct position. Well thats the position i set mine at and tbh thats what i took it to be from my haynes manual...............no problems with mine

 

[kebab]

for future reference you should time the bottom end using the slot and 0 degree pointer on the fly wheel, its far simpler.

 

[NumanR]

Yes its much easier to pop out the rubber cover on the bell housing and use those marks, more accurate too.

 

[KwikPhix328]

Thanks for the replies, much appreciated.
The only reason that i looked into this matter in slightly more detail was because i had the head off to change the gasket. I had access to a Dial Test indicator form work and then bought myself a little magnetic DTI base from Machine Mart ( see updated pictures).

According to the Haynes manual you can check for TDC using a DTI too, (method 'B' as they call it), obviously this is much easier with the cylinder head off.

The thing that I find most surprising though is that using precision measuring instruments, the Oil Pump reference point and the actual TDC are about 1 crank tooth different !

INSANT UPDATE:

Phew, you guys really are the best ! I wish the Haynes Book and the Fiat WM that i have on CD pointed me to the Flywheel mark.

After checking and re-checking with the DTI this afternoon I was so convinced of the difference that I stuck my neck out and made another notch on my Oil Pump web (see picture). After reading this post I set the engine to TDC using my new notch and then cross checked with the flywheel mark, you guessed it, they both lined up perfectly . I then rotated the crank clockwise further so that my pointer was lined up with the original refernce mark ( at the 'Apex' ) and the notch on the flywheel was no longer visable through the bell housing 'window'.

The bell housing mark is so easy to find too .

 

[Oldschool]

All you have to do is lign up the cam pulley mark with the notch behind the cam pulley on the head and place the yellow mark (sometimes white) over the notch on the cam pulley and do the same on the crank pulley.