cant find TDC on the flywheel, is this the mark on the cam gear?
#1
Mexican Ambassador
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cant find TDC on the flywheel, is this the mark on the cam gear?
as titled, i've got everything apart, i cant find the "OT" mark that Clarks says to look for on the flywheel cuz it's kinda rusty, so i yanked the belt covers and i'm wanting to know how to find TDC on the cam gear.
i got it to here-
and another pic-
i looked in the little hole, but i didnt see any kind of mark anywhere.
and the belts dont even really look that bad. not any worse than the brand new ones i just bought, but the balance shaft belt looks kinda worn.
just for future reference, are these fairly worn belts?
i think i'm done for today, if it doesnt rain during the week, i'll just end up finishing it bit by bit after work.
(btw- air ratchets are TEH WIN. i got everything off up until the pictures above in like, half an hour. it usually takes me like, an hour just using regular ratchets.)
i got it to here-
and another pic-
i looked in the little hole, but i didnt see any kind of mark anywhere.
and the belts dont even really look that bad. not any worse than the brand new ones i just bought, but the balance shaft belt looks kinda worn.
just for future reference, are these fairly worn belts?
i think i'm done for today, if it doesnt rain during the week, i'll just end up finishing it bit by bit after work.
(btw- air ratchets are TEH WIN. i got everything off up until the pictures above in like, half an hour. it usually takes me like, an hour just using regular ratchets.)
#2
Race Director
OK if you were lucky someone wuold have put nail polish there..
What I do is bring it to TDC (according to the cam) and then put a WOODEN dowel/rod in #1 spark plug hole (make sure its long enouigh not to fall in) and turn the motor over SLOWLY until it doesn't rise anymore. Theres a few degrees of rotation when its like this. Then look at the mark on the flywheel. You should see "OT" with a line right under it.
On my old N/A I couldnt ever find the mark but had the belts off and the motor moved and never had a problem. .. other cars as well!
Edit- Looks like that is TDC based on the marks + the rotor being pointed at #1 but if you want to be sure you can use the dowel trick
What I do is bring it to TDC (according to the cam) and then put a WOODEN dowel/rod in #1 spark plug hole (make sure its long enouigh not to fall in) and turn the motor over SLOWLY until it doesn't rise anymore. Theres a few degrees of rotation when its like this. Then look at the mark on the flywheel. You should see "OT" with a line right under it.
On my old N/A I couldnt ever find the mark but had the belts off and the motor moved and never had a problem. .. other cars as well!
Edit- Looks like that is TDC based on the marks + the rotor being pointed at #1 but if you want to be sure you can use the dowel trick
#3
Nordschleife Master
It took me a while to figure out how to find the mark on the flywheel on my n/a car. Just lighten the area with a flashlight and you should see the OT mark. If you dont see it, try rotating the engine over again once. If you still dont see it.. then it could just be rust on the flywheel like you said. In that case, crawl under the car and check for the notch on the flywheel which lines up in the bellhousing slot.
EDIT - Based on your pictures, your looking in the wrong spot for the flywheel mark. The mark is seen from ABOVE the car, look down by the oil fill tube, you will see a little window next to the speed and reference sensors. Its not exactly easy to see on my n/a car and probably not much easier on your turbo. A powerful flashlight is really needed here.
EDIT - Based on your pictures, your looking in the wrong spot for the flywheel mark. The mark is seen from ABOVE the car, look down by the oil fill tube, you will see a little window next to the speed and reference sensors. Its not exactly easy to see on my n/a car and probably not much easier on your turbo. A powerful flashlight is really needed here.
#5
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ok, i thought it looked way different from the clarks schematic, but he takes pictures that are so damned close up, that you cant see anything.
this is a turbo, i can see anything when i'm looking into the engine bay.
i'll try the dowel trick and try to find the window where i'm supposed to see the mark on the top.
i rotated the crank 2 whole times andmy friend didnt see anything.
i had him do it twice and didnt see anything in the hole.
but i'll keep at it......
thanks, guys.
this is a turbo, i can see anything when i'm looking into the engine bay.
i'll try the dowel trick and try to find the window where i'm supposed to see the mark on the top.
i rotated the crank 2 whole times andmy friend didnt see anything.
i had him do it twice and didnt see anything in the hole.
but i'll keep at it......
thanks, guys.
#6
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95Juan,
I haven't owned a 951 but the regular 944 has a mark you can use on the bottom of the bellhousing. There's a little notch on the bottom of the bellhousing. Turn the engine so that a groove cut into the flywheel lines up with that notch and the #1 piston is at TDC. You can also verify that your cam timing is spot on as the mark on the sprocket should match the notch on the outside housing.
You will have to get under the car to and look at the bottom of the bellhousing.
I haven't owned a 951 but the regular 944 has a mark you can use on the bottom of the bellhousing. There's a little notch on the bottom of the bellhousing. Turn the engine so that a groove cut into the flywheel lines up with that notch and the #1 piston is at TDC. You can also verify that your cam timing is spot on as the mark on the sprocket should match the notch on the outside housing.
You will have to get under the car to and look at the bottom of the bellhousing.
#7
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i was checking at the bottom hole, that's where the pictures are.
i rotated the engine twice with two different people looking and a flashlight pointing straight in there, but neither of us saw anything.
i'll try the dowell thing, cuz i guess the flywheel is just rusty or something.
i rotated the engine twice with two different people looking and a flashlight pointing straight in there, but neither of us saw anything.
i'll try the dowell thing, cuz i guess the flywheel is just rusty or something.
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#8
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If your timing is correct, once you have the mark on the cam gear lined up, you're done. You don't need to check the flywheel. Lock the flywheel and go to step 2.
The dowel will go up and down go thru two cycles for every rotation of the cam gear so you have to know which one is TDC and which is not.
The dowel will go up and down go thru two cycles for every rotation of the cam gear so you have to know which one is TDC and which is not.
#10
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On the bottom of the flywheel (when at tdc) you should see a notch in the bell housing that I think is around 1/4 inch or so... inside, you'll see a similar notch on the flywheel. make sure that's centered in the notch on the bell housing, and you're good. also, the way you have it right now is good. I go by the cam, then check on the bottom of the bell housing, and it's not failed me yet.
#11
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Originally Posted by 95Juan
i was checking at the bottom hole, that's where the pictures are.
You were checking at the "clutch inspection window". that won't do diddly sh*t except tell you if your clutch is good... and even then, it takes measurements within the window...
#12
f your timing is correct, once you have the mark on the cam gear lined up, you're done. You don't need to check the flywheel. Lock the flywheel and go to step 2.
I couldn't find mine with the belt on either. Once I removed the belt I turned the crank very slightly one way then the other until it was in view. I think the po had the belt off one tooth and then with belt stretching it was off a bit more. You can do the same with the belt on, try very slight increments ~1/4 tooth at a time either way.
#13
Race Director
Are you doing a timing belt job?
If so just don't rotate the motor (AT ALL with the belts loose/removed) and put the belts back on. Use a flywheel lock (much better then other option) or even something wedged in the flywheel teeth if you really have to...
If so just don't rotate the motor (AT ALL with the belts loose/removed) and put the belts back on. Use a flywheel lock (much better then other option) or even something wedged in the flywheel teeth if you really have to...
#14
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I found that sometimes the flywheel mark will zipp by and go unseen.
After you get the cam mark lined up turn the crank clockwise about an inch..
Then slowly turn counter-clockwise until the mark shows up and the cam lines up.
When I played with it the cam would line up perfect when I turned the whole thing slowly counterclockwise.
when I went past it and turned the crank clockwise it would not line up.
There may be that much play in the system I don't know.
I had to lean way over the drivers fender and look almost straight down to see the 0TC mark through the retangular hole almost on the top of the bellhousing.
A friend of mine tried to use that round inspection hole on the bottom and bent all his valves that way.
JC
After you get the cam mark lined up turn the crank clockwise about an inch..
Then slowly turn counter-clockwise until the mark shows up and the cam lines up.
When I played with it the cam would line up perfect when I turned the whole thing slowly counterclockwise.
when I went past it and turned the crank clockwise it would not line up.
There may be that much play in the system I don't know.
I had to lean way over the drivers fender and look almost straight down to see the 0TC mark through the retangular hole almost on the top of the bellhousing.
A friend of mine tried to use that round inspection hole on the bottom and bent all his valves that way.
JC
#15
Race Car
The OT mark goes by pretty quick, turn the engine 1* at a time, very very very slowly. I use a long bar just to get fine enough control.
Next, you are looking through the wrong inspection hole. None the less you should have seen the mark go by (if you were sitting there watching the flywheel spin.
I find the easiest thing to do is to remove the bottom metal cover from the flywheel/bellhousing (4 bolts?), and find the OT mark down there, then paint it with some white out or a marker of some kind. Re-install the cover and look for it in the top inspection hole (beside the speed/reference sensors, get a box to stand on to help you see it).
Next, you are looking through the wrong inspection hole. None the less you should have seen the mark go by (if you were sitting there watching the flywheel spin.
I find the easiest thing to do is to remove the bottom metal cover from the flywheel/bellhousing (4 bolts?), and find the OT mark down there, then paint it with some white out or a marker of some kind. Re-install the cover and look for it in the top inspection hole (beside the speed/reference sensors, get a box to stand on to help you see it).