carolinajk

also the 3.6 is an open deck engine which in my opinion is a cheap way to build that gives up strength as there is little support around the cylinder bores .the exhaust valves are dissimilar metal with a stem that is welded to the face i wonder if that is where the dropped valves are. i would be wary , not just of this engine but all of the manufacturers engines that wring high hp and torque out of smaller displacements. i just dont think the long term durability will be there . not only that but they are making them so lightweight and monkeying around with new materials so much that , well call me skeptical. im not bashing here just my opinions . these things have How many timing chains? 4? and all the associated tensioners and guides . just so many more parts and potential for things to go wrong . not to mention the backyard guys who will never be able to do alot of their own work anymore and fewer and fewer young guys are developing into top notch wrenches to work in dealerships . idk just lamenting the loss of simple shit

airforce26yrs

Amen, I miss the days that I could fix my own vehicle. Lets go back to points, plugs, condensers and carburators.

Sunkist Rubi

[QUOTE=carolinajk;2987944]The 3.6L uses a hydraulic actuation for it's valve train. The hydraulic lifter, Chrysler calls this part a "Hydraulic Lash Adjustor" contacts, under hydraulic engine oil pressure, one end of a pivoted rocker arm assembly. This pressure is forced through the rocker arm assembly where a cam roller/follower stays 100% connected to the entire circumference of the cam surface as it rotates 360 degrees. The rocker arm assembly is attached to the end of an exhaust or intake valve at the opposite end.

What's causing the ticking is the lifter isn't creating enough pressure to keep the cam roller/follower in constant contact with the cam. As we all know a cam has a lobe that actuates, or forces, an intake or exhaust valve to open. Because the cam roller/follower isn't being kept in constant contact, when the cam lobe rotates into position it bangs into the cam roller/follower causing a tic. An excellent engine cutaway is available online showing this valve system by searching under allpar 3.6 pentastar technical.

The debate begins as to what is causing the lifter not to have enough pressure to hold the cam roller/follower against the spinning cam. If you read enough online forums on this topic, there are quite a few, the majority of the repondents with this problem end up having their driver's side head replaced. Also it has been brought up many times by these respondants that there is a huge back order for these heads. Which would only amount to one conclusion the HEAD is the cause of this problem.

Concerning the head causing the problem: The lifter is installed in a cast bore integral with the head. There is an extremely close tolerance fit between the lifter and the head's lifter installation bore. If this bore's diameter is just a touch larger, out of round, or with an incorrect surface texture, in other words not to print; too much engine oil will get by and not pressurize the lifter sufficiently to do what I described above.

carolinajk

i get the operation , it is just the way these guys are saying the dealer techs throw terms like lifter and lifter bore around like its a cam in block design looks like they could use the correct terms is all. also thanks for the info on the follower . i know these engines use two piece exhaust valves though just curious as forever one piece or sodium filled valves have held up quite nicely

rokov

Just because the oil "looked good", doesn't mean that it was. You would have to take it to a lab to see if it was okay

2012jkunlimited

Build date of 7-11 no tick for me. Knock on wood. I have put 31k miles on it.

ninjamaster

It wasn't low. Almost full on dipstick. Thats all I was getting at.

rtguy1

Umm..I'm not really sure what you are specifically talking about. Since this is the JK forum I assume you are talking about the 3.6 motors in wranglers. As I said before, they are produced in the U.S. only. You can check window stickers all day and never find one that says Engine: MX. Take a look at other Chrystler vehicles, like the 200, grand Cherokee, etc. The 3.6's coming from Mexico are going in different Chrysler vehicles. Allpar is not wrong, as there are plenty 3.6's being produced in Mexico, just not for the Wrangler. The major tick problem has nothing to do with assembly either, it's the cast/machining that is the issue.

Here the sticker from a Chrysler 200 for an example:
PARTS CONTENT INFORMATION
FOR VEHICLES IN THIS CARLINE:
U.S./CANADA PARTS CONTENT: 73%
NOTE: PARTS CONTENT DOES NOT INCLUDE FINAL ASSEMBLY,
DISTRIBUTION, OR OTHER NON-PARTS COSTS.
FOR THIS VEHICLE:
FINAL ASSEMBLY POINT:
STERLING HTS, MICH., U.S.A.
COUNTRY OF ORIGIN:
ENGINE:MX
TRANSMISSION:US

JJBiggs

12-2011 build date. Mileage = 2800 or so.

Ticking is prevalent on driver's side and seems to be getting louder. No codes, no misfires so far. Only a rough rumble every now and again.

Paying attention to it for now. Will post if things develop further.

JJ

slappygoeshome

buid date 1-12.....and its ticking....we should start our own 3.6 tickstar club everyone with a tick ill buy you a ....and ill buy myself one too..... on a more serious note should I wait to go to the stealership or bring it in now? also I purcharsed my jeep in NY and moved to VA on mil orders....does it matter?