Timing Guide/Tensioner Failure/CamLock | Ford Explorer Forums - Serious Explorations

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January 23, 2018
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2004 Ford Explorer V6 4.0 K series XLT 2 Wheel Drive. 146K and never been serviced. Got it off a guy about a month ago. Drove it ran rich with a bunch of fuel issues. Fixed all the issues and got it cleared ready for smog. Few days after, TIMING TENSIONER goes bad and caused the REAR GUIDE to bust & THE CRANK TENSIONER to bust as well. Driver side tensioner just failed but the Guide was ok. PULLED THE ENGINE TO find a remanufactured Trans. I've done the OIL CHANGE/SPARK PLUGS/VALVE COVER GASKET/EGR so far. Engine turned on even with 2 out of 3 guides busted no problem just super loud clanking. Either way, engine is out on the stand. Had a tough time cranking it 6 revolutions to get it all on TDC. plastic was lodged behind the REAR lower sprocket. Literally could not over turn cams to get any movement to undo the jammed plastic. I decided to lock the Harmonic, take out the spark plugs an make sure no valve marks were on the piston heads. No marks, and cylinder 1 and 5 are confirming TDC is set. I have no choice to loosen up the FRONT CAM SHAFT BOLT AND SPROCKET, while on TDC w/ the Cam Shaft Sprocket locked to the block. As soon as it loosens the driver side cams made a noise like the FRONT cam springs released the tension and shifted the the driver side cams to match and are now identical with the REAR passenger side timing marks in the direction of 3 and 9 o'clock. I look in the in the spark plug journal to see the piston head an everything is still the way it was when I started...my question is WHAT DID IT POSSIBLY DO WHEN I RELEASED THE FRONT CAM SHAFT BOLT? The Rear Cam Bolt has never broke the seal yet. The front cassette and cam shaft sprocket is off. OIL PAN AND LADDER ARE COMPLETELY DROPPED. I'm hoping my timing may be a slight hair off an can be adjusted to still come through with a fix , but I've searched an no one I've seen so far had this happen in that sequence. I have the timing guide kit. CHAINS/ SPROCKETS/TENSIONERS & GUIDES. Getting a few more things as well to but before I do I need to know. Is it going to be ok? And how do I set the timing for the cams back manually with out damaging anything??




Lol, there are no timing marks. Search for the OTC6488 before you put anything back together and you will see what is going on.

I know there's no marks that's why I'm asking, there's only the cut grooves in the back of each shaft like in the photos. does it just have to be flush with the valve head? If so then why get the tool?? 6mm Allen keys an vice grips will lock it in place. Both cams need to be retimed so I'm wondering is it a series of revolutions that set it..like the balance shaft below the block? Or is there a specific way to time them individually? Both cams are still joined by the REAR the FRONT is loose. An that's what made the driver side cams either lock or lose it's timing.

There is a tool in the kit that holds the crank at tdc. Then you do the cams one by one. the tool locks the cam to the top of the head so it cant turn. There is also a tool that holds the chains taught so they are at specific tension, if not the timing will be out. You do one side, the the other. If the crank doesnt move, and a side is complete, it may move when the tensioner tool is out, but it will still be in time when the actual tensioner functions. If you can get all the pieces of this jigsaw puzzle into place without the tool, then you can pull it off.

if you look closely at the slots on the cams, they are off center, Have a look, but I think they have to be on the low side. With the OTC tool they only fit one way. If you get them upside down the valves open 180 deg out of phase, and it wont run worth a crap. Being a wasted spark ignition system it will still run though.