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i have a 2005 ltz 400 i went torque y cam caps down and the bolts just kept spinning. dose anyone know what's the measurements for the Heli coil i can use on this?
 

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happened to me too many time as well...
 

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Dip your drill bit in grease and drill very slow. The grease will keep most of the shavings stuck to the bit. You can also wipe around the hole with acetone to remove oil and form a bowl out of duct tape, stick it to the head, then use a razor blade to cut out the hole you need to drill. Clean the bit and re-coat with grease often. Once you’re done, wipe any shavings off the “tape bowl”, remove it, and blow the head out with compressed air to get any shavings that got away out of the head.
Be sure the bolts are in the correct holes. The 2 that have a skinny shank go on the insides of the sprocket end of the cams. If they aren’t thin-shanked, you’ll block the oil passage to the exhaust cam and starve the cam journals of oil.
Both the cam cap bolts and the valve cover bolts are very sensitive to torque and must be installed with a reliable torque wrench. If the valve cover bolts are over-torqued, they can snap the cam caps, which requires a new head.
 

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What ya mean Jet?
there is 6 identical bolts , and 2 bolts a bit longer ones, one on each side of the top cam chain slider , i didnt notice they were skinnier then the rest of the 6 or something ...
 

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Be sure the bolts are in the correct holes. The 2 that have a skinny shank go on the insides of the sprocket end of the cams. If they aren’t thin-shanked, you’ll block the oil passage to the exhaust cam and starve the cam journals of oil.

I think you have this part mixed up with something else Jet. There aren't any skinny shank bolts in the head of the Z. There are 2 longer bolts, which both go on the exhaust cap, on the side towards the sprocket.
 

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while we one the subject , how does the oil fly to the head in general , like the oil pump pump it Through where?
and how does cam journals get oil under the caps?
 

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while we one the subject , how does the oil fly to the head in general , like the oil pump pump it Through where?
and how does cam journals get oil under the caps?
The oil passage that feeds the top end, comes up through that little brass oil restrictor under the cylinder. That passage goes straight up through the sprocket side cam bearing on the intake cam. There's a passage drilled from the same place in the exhaust cam journal that connects to the other passage.

Oil flows through the camshaft to get to the other cam bearings.
 

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The oil comes up a passage near the cam chain tensioner (a bolt that goes to nothing is there to remove as a witness hole to verify you have oil supply to the head).
The oil then goes through the same 2 bolts that hold down the metal piece that acts as a cam chain guide between the cams. If you pull those cam caps nearest the sprockets, you’ll see the passage. The oil actually flows around the bolt shank to get though it. If you replace those bolts with regular threaded bolts or do something like put RTV or gobs of threadlocker on the bolts, it can block that passage. The factory green Suzuki bolts, if you look at them closely, has a narrower shank than the threads for that reason. I know this because that’s what the previous owner did to my Z before I got it and it starved the exhaust cam of oil. Any bolt from Ace hardware can give you problems.
Here’s the parts diagram:

There is a common misconception that the 2 longer bolts (item 4) go on the inside and need to be longer due to the extra piece of metal, but the parts fiche shows them going on the outsides of the cams.
But yes, I misspoke. They all have skinny shanks, just two of them are longer. It’s been awhile, but I remembered something was important about using factory bolts, not aftermarket.
 
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This is the cap I’m talking about:
 

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good info guys , i will squeeze any bit of info i can get ...
 

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Weird, it didn’t like my pic.
0C228393-F71B-47E9-A9ED-0BB5B76F5E6A.png
 

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The top left of the pic is where the alignment pin goes and, according to the parts diagram, it gets the longer bolt. The bottom left is the oil passage. You can see that if you put an aftermarket bolt with threads all the way up the shank, it pretty much blocks that passage, especially if you put some kind of goop on it. The shank needs to be smaller than the threads to allow oil to get to the cam.
 

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You're right about the way that works, but there's nothing special about those bolts. I have several of them around here. I can only tell them apart from other allen head bolts because of the flange they have on the head of the bolt. The shank is typical of any M6 x 1.0 bolt of that length. The hole in the cap is oversized enough to allow oil flow around the bolt. Goop on the bolt could definitely plug things up though.
 
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