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Discussion Starter · #1 ·
Hi guys, just a quick question please. Need to clear up a confusion. Looking to do a leak down test due to possible head gasket failure. I need to be in TDC per each cylinder when testing.

Now the manual says to align the mark "k" with (b). Is this actually TDC position, with all valves closed? Or this is BTDC?

Is the second picture actual TDC? And would it be ok to just follow the valve clearance check procedure in the manual to find TDC for each cylinder or would the procedure in the manual be BTDC?

Also is there anything else you guys could suggest, tips or tricks for the leakdown test? Is the head gasket a tough job to do?

Would appreciate the help and knowledge. Thanks.
 

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The valves on cylinder 1 are closed on the compression stroke at the k mark. Is it actually tdc? Technically no. It's just past tdc. Valves are closed though so you can leak test there.

Pro tip, remove the cam cover and actually look at the cams when you leak down test.
 

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Discussion Starter · #3 ·
Thanks for reply. So is that the first pic with the marks on the left at 9 o clock or the second picture with the marks around the 12 o clock up top?
 

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The line on mark k lines up with the split on the case at roughly the 9 o'clock. If you are on intake or exhaust stroke, the valves aren't closed, so you need to be on compression stroke. Again, look at the cams to determine stroke. If the cam lobes are facing away from each other at ~10 and 2 o'clock, you're good.
 

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Discussion Starter · #5 ·
Ok cool thanks. Yup I will make sure it's on the compression stroke. So is this 9 o'clock position actually TDC or BTDC? And is this position OK to test all cylinders or only #1 in this position?

It is my understanding for valve adjustment clearance check should also be done at TDC so why is that starting position at the 12 o'clock. Just looking to gain some knowledge lol. Thanks again for replies.
 

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Also, to leak test each cylinder you will need to roll the cams. I use the crank for that. With the cam cover removed you can look at the cams and test the cylinders as they come to tdc.
 

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Also, for a valve adjustment according to the factory manual for my 08, you line up mark k. What manual are you using?

Stupid cross plane. Here, you'll find this thread useful;

The k mark on the 09-14 is btdc and for timing purposes. The line on the pickup coil is actually tdc. As you mentioned above.

If you look at the actual lobes though, you can basically ignore the Mark's because you can physically see the valves. Then look at the crank mark and know which is which. Looking at the lobes is fool proof.

Sorry for the misinformation. I haven't worked with the cross plane platform before and just assumed it would be like literally anything else. Kawasaki, honda, hell even Yamaha. But no, it's, different.
 

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Discussion Starter · #9 ·
lol yes its a 2009 crossplane. I have the 2009 R1 service manual. So according to that link you sent, the 9 o'clock is infact BTDC. So accurately it would TDC at the roughly 12 o'clock position, and ofcourse all in relation to the K mark on the sprocket. I would prefer not to remove the valve cover if I dont have to. Thats why I was asking if I just follow the valve clearance directions in the manual for inspection, it should place all of the cylinders 1 by 1 into TDC, is my understanding, allowing me to check each cylinder. I will actually be removing the throttle body so I will be checking the valves seating as I rotate the crank to make sure they are in the closed position. Sounds like I will be ok? lol
 

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Yea bud, that should get it. I really didn't expect the same denso ignition to be different in the 09, so again, that's my bad. I think you've got it now though, and hell, I got to learn something too.

Good luck bud, you've got it now.

One more pro tip, you can stick a dowel in the spark plug hole and see top dead if you don't want to remove a cam cover.
 

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I put a long 1/4” socket extension down the spark plug holes to confirm TDC. A straw works as well. The mark on my 06 crankshaft is ever so slightly off (important when reinstalling the cams for timing purposes).
 

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Discussion Starter · #12 ·
Cool. Thanks for the replies guys. Yes I was actually thinking of using a straw for visual reference also lol.
 
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