2003 4.7 Durango engine noise
#81
#82
Not really "free play", but you should be able to depress the plunger if there's no oil in the lifter. It'll still give some resistance, but just from the spring under the plunger, shouldn't be that difficult to move the plunger. Just be careful how much force you use in your vice, and how quickly. All you're after here is to squeeze the oil out of the lifter so you can check to see if the plunger is moving like it should. Put too much force on it too quick, and you could damage a lifter that has nothing wrong with it.
The compression test is an excellent idea, and probably should've been done before you pulled the cam and lifters, but no sense in second-guessing things now, and it won't be difficult to drop the valvetrain back in for a compression test. All you need is the cam, lifters, and timing belt/chain in place. Valve covers, timing cover, etc. can all wait until you've verified compression. Also, be absolutely sure those lifters are working before you put them back in, and try to put them exactly where you got them from. I'm sure I don't need to tell you why
The compression test is an excellent idea, and probably should've been done before you pulled the cam and lifters, but no sense in second-guessing things now, and it won't be difficult to drop the valvetrain back in for a compression test. All you need is the cam, lifters, and timing belt/chain in place. Valve covers, timing cover, etc. can all wait until you've verified compression. Also, be absolutely sure those lifters are working before you put them back in, and try to put them exactly where you got them from. I'm sure I don't need to tell you why
#83
#84
The new lash adjusters (lifters) will need to pump up with oil before they'll operate properly. A good idea before installing them is to submerge them in a can of oil and "pump" the spring a few times to fill them with oil.
I hope you've found your problem, but I kinda doubt it. (sorry!) If a valve adjuster fails (pumps down) the rocker will rattle and possibly fall out of place, but it makes more of a "clattering" sound. Pretty common on the 4.7's. If you have two that are fully extended and not compressing at all it'll cause premature wear on the cam / rocker assembly, but I don't believe it'll cause the valve to hit a piston. Unless the cam is out of time, the valve is still going to close when the lobe rotates off of the rocker. Even fully extended the lash adjuster isn't long enough to cause a valve to open.
Bob
I hope you've found your problem, but I kinda doubt it. (sorry!) If a valve adjuster fails (pumps down) the rocker will rattle and possibly fall out of place, but it makes more of a "clattering" sound. Pretty common on the 4.7's. If you have two that are fully extended and not compressing at all it'll cause premature wear on the cam / rocker assembly, but I don't believe it'll cause the valve to hit a piston. Unless the cam is out of time, the valve is still going to close when the lobe rotates off of the rocker. Even fully extended the lash adjuster isn't long enough to cause a valve to open.
Bob
#85
Working on replacing the left side lifters. Yes, I did the old school trick to soak the lifters before installing them. I should have it buttoned up tomorrow and then I will check compression although I think it is fine. I still think there is something funky with the timing chain and I don't know how to identify if everything is fine or not. Once I get the lifters and cam back in I will spin the engine without the plugs in to observe the timing chains. Also, I am resetting the tensioners after I get the cams back on.
#87
I have video of what the timing chain is doing while cranking the engine. The tensioner is popping up and down and you can see the slack in the chain hitting the top guide. The left side appears fine. So is this a bad tensioner...it is brand new. Sorry the sound is messed up...
http://www.youtube.com/watch?v=gaxva...&feature=feedu
http://www.youtube.com/watch?v=gaxva...&feature=feedu
Last edited by dmeray1; 11-10-2011 at 11:06 PM.
#88
Check the teeth on the gears for extremely worn or actually missing teeth. I can't think of anything else that would cause that thing to jump and bounce like that. The tensioner is trying to do it's job, it's just that something is causing the slack to fluctuate pretty wildly. I'd think that it should operate pretty smoothly. That is not smooth.
[EDIT]
One other thing I wanted to ask: Does that tensioner use oil to keep pressure on the chain? If so, it might not smooth up until the engine has been run, or you've pumped the tensioner up with oil.
[EDIT]
One other thing I wanted to ask: Does that tensioner use oil to keep pressure on the chain? If so, it might not smooth up until the engine has been run, or you've pumped the tensioner up with oil.
Last edited by brhodes; 11-10-2011 at 11:22 PM.
#89
I rotated the engine by hand and even though the bottom side is taught, the top side goes slack a couple of times through the cycle. This is a new timing chain set. The left side chain stays taught throughout the cycle. I did remove and reset the right side tensioner and that helped...apparently the stop did not go out far enough the first time and did not put enough pressure on the guide. But I am still seeing this slack in the chain. Maybe I should reinstall the old chain and sprockets?
#90
Here is a video with the tensioner reset. Does not bounce as much but is not as steady as the left side.
http://www.youtube.com/watch?v=s-DDH...&feature=feedu
http://www.youtube.com/watch?v=s-DDH...&feature=feedu