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Engine & Gearbox / 1991 1.6 EZ petrol 8 valve timing marks discrepancy
Someone before I owned the car has put an aftermarket carburettor on it, ( I don't know what brand, I don't know how you tell), I have not owned a car where I've swapped out the standard carburettor for a different one so a bit out of my depth here. The carb that has been fitted comes with it's own filter that sits directly on top of the carburettor, as the shape of the whole is oval but the air box has a standard circular whole, so things have been made to fit, I don't know if this is the cause of the problem or simply just adjusting the fuel jets in the carburettor. In case your wondering I have added this information for transparency on what might be the route cause of the issue.
So back to the timing, I was looking at what the timing marks are meant to be etc, I have a Haynes manual and through that but hasn't seemed to be much help to be honest. It seems most people align there cam with a mark on the back of the cam with the top of the head where it meets the rocker cover. However just to make my life even more difficult, my timing mark for the cam is different. I have a plastic back plate situated between the camshaft and engine, and there is an arrow on the plastic back plate with the letters ot next to it, on the camshaft pulley I have a mark that also has the same letters next to, now logic might dictate this is the timing mark. From what I have read online I think it is. However there is a second mark on the camshaft which is just a dot, similair looking to the one on the intermediate pulley which is what turns the distributor.
Now comes the fun part, there is meant to be an engraved small vertical line in the auxiliary crankshaft pully which also aligns with a dot that I mentioned above, on the intermediate shaft pulley. I can not see this line anywhere, I have taken the pulley of spun it round multiple times in my hand looking for one, it just isn't there. There is still some paint which is peeling off in various areas around the pulley, I don't know if it is original paint, or if someone has repainted it, and the paint is cover the vertical line.
I have been able to locate the marks on the distributor with the cap off, which is nice and simple.
I have left the most confusing part till last, the flywheel! I have removed the bung from the gearbox, but haven't been able to remove the outer plastic part which is screwed into the gearbox, I will have to invest in a giant allen key if it becomes apparent that this needs to be removed. On the flywheel I have several different notches, and engravings you name I seem to have them all. I have already read online and most seem to use just one, and again the haynes manual isn't great at providing information for this. So I have a diamond engraved and then 2 separate engraved dots, which are directly next to each other, but you see one then turn it a bit more and see the second, or at least it looks like there is 2, but it is oily on this part of the flywheel so a little hard to make out. Additionally to this I have what some may refer to as a VW timing lug which is used with a specialist vw tool, I believe I actually have two of these as well. I was able to locate this guide from another forum: http://www.cabby-info.com/Files/AdjustingTheTiming.pdf go to page 2 in the pdf I seem to be able to see both the step 2 image and the notes image.
Now from what I have gathered from some limited research most people use the engraved dot located next to the engraved shape, I think it looks a bit like a diamond or an arrow, but if I line up the ot mark on the camshaft pulley to the mark on the plastic backing plate, this also means the distributor is aligned, but when I check the flywheel I see the timing lug, and not the engraved dot and diamond shape. In order for me to see those, the camshaft pulley mark is 180° and so is the distributor.
I do believe it has had a clutch in it's time, I know the flywheel usually doesn't come off for this procedure, I don't know if someone has removed it for some other reason, I do have a record of a timing belt replacement as well, so I don't know if it was incorrectly aligned previously. On some of the flywheel marks though they have been tipexed for some reason.
I have changed the belt today, and just used the ot mark as it seems like it is what was used in the past and I think it is the correct mark, I didn't break my engine, and it runs how it did before I changed the belt, I just ultimately want to resolve this issue, and get to the bottom of these marks on the flywheel and which one I am meant to be using.
If anyone could help clarify what marks I should actually be using, whether this is causing my idling and slight erratic idling etc issues, as I have read that it can cause issues with idling etc if the timing isn't set correctly.
Here is a picture that has the timing marks which I can also see on the flywheel, when the cam is timed, I believe I am seeing the right most timing lug, and in order to see the TDC mark, the cam needs to be 180° out, I think I can also see to marks which both look like the TDC mark, but it is oily on that part of the flywheel, so not easy to tell. Ultimately I want to know if the flywheel being out would cause me my idling and starting issues, and whether the flywheel being out is something that needs to be rectified.
Carburettor photos:
