[rodrigogodoyv95]

Mmm, i think plated links don't come to the same position after you rotate the sprockets. Anyways, yes, plated link in the idler sprocket is at 12 o'clock position at the beginning, also, there is a plated link and an arrow in the crank sprocket that need to match (along side with the dimple mark in the crankshaft and the block junction). That is also set up properly before start rotating. The only slack i see is in the left cam chain.

How do i fix this slack anyways, is there some kind of method to do this? All tensioners are new.

I also tried to jump one tooth back in the crank sprocket, no luck too, dimple mark in the crank got too far back from the block junction mark.

 

[rodrigogodoyv95]

This is the slack from the left cam chain once every tensioner is released. After two full rotations, there is no more slack, but dimple in the crank is off by a few degrees.

This is what i found in another forum about head resurface and chain slack: "When you mill the head .010", you have that amount 2X in excess belt length. When the tensioner takes up that slack with the crank in the same position, the cam turns counter clockwise, which is retarding relative to the crank position."

That exactly is happening to this engine, if i stop when the crank dimple and the junction mark in the block match, all camshaft got retarded a bit. So if i keep turning the crank to make all camshaft sprockets match, the dimple in the crank got off position by a few degrees.

Idk how much material was removed from this head, but this engine was definitely open.

 

[ImperialCrown]

Correct. The plated links are only for the initial timing set-up. Turning the crankshaft over 2 turns, you will lose the plated link positions, but the sprocket marks should match the positions that they started out as.

 

[AllanC]

. . . .i think plated links don't come to the same position after you rotate the sprockets. Anyways, yes, plated link in the idler sprocket is at 12 o'clock position at the beginning, also, there is a plated link and an arrow in the crank sprocket that need to match (along side with the dimple mark in the crankshaft and the block junction). That is also set up properly before start rotating. The only slack i see is in the left cam chain. . . . .

I believe you have the 2 tensioners installed correctly on the crankshaft to intermediate sprocket assembly drive chain?

My error on thinking that the plated links would return to initial timimng position in 2 crankshaft rotations. I am still thinking of a direct drive from crankshaft to camshaft. In that arrangement the camshaft sprocket is twice the diameter of the crankshaft sprocket. That gives a 2 : 1 where crankshaft makes 2 revolutions to 1 revolution of the camshaft.

Howver this Pentastar V6 has an intermediate drive sprocket and that complicates things. I do not know the drive ratio between crankshaft and intermediate sprocket; I will call it ratio A. There is another drive ratio between the intermediate sprocket assembly and the camshafts; call it ratio B. You multiply the 2 ratio fractions together and you get a ratio between the crankshaft and camshafts of 2 : 1.

I believe if you continued to turn the crankshaft additional turns that plated link on the crankshaft to intermediate sprocket assembly would eventually appear in the 12 o'clock position. and the dimple on the crankshaft would be at or close to the block parting line. The plated links on the camshaft chain will be in their original timing position.

. . . .How do i fix this slack anyways, is there some kind of method to do this? All tensioners are new. . . . .

So you have convinced me that head shaving does cause excess chain slack and this causes a slight misalignment of the timing marks as you have noted. If you could find 2 camshaft to intermediate sprocket drive chains that are a few thousands of an inch shorter in length that would correct the problem. But I highly doubt such a modified chain is available.

You could try and move the fixed guides on the camshaft drive chains. Do not know if there is room to move the fixed guides to remove slack. See attached image.

I wonder if thicker head gaskets are available for the 3.6 liter V6 engine? A thicker head gasket would remove some if not all of the chain slack and remedy the situation. In a sense a thicker head gasket has the same effect of increasing the deck height. Do not know if thicker head gaskets would create sealing issues?

 

[rodrigogodoyv95]

This is the first time i have encounter this issue, i have done plenty of engine overhauls, this one falls in the category of extremely hard to fix ones (in the budget). Actually, a custom chain guide would be a really good solution, aswell as a thicker head gasket, a custom made one to recover all the height lost. Idk why the guys that did the previous job in the engine used those head gaskets... Anyways, i don't know if the customer would like to spend more money on this job, i don't think so.

I like this forum a lot, really useful help and way active in comparison to other forums, a shame is only Chrysler related, idk when i will post again for another advice as i work with multiple brands that come to the shop. Thanks both for your time.

 

[ironpony]

this is similar to an issue we had with a Subaru years ago. Line up all the marks, rotate the engine and they do not line up. Contact Subaru and they confirm, say it takes IIRC several thousand revolutions before everything lines up again.
Line up the marks and you are good to go.