Rob G B
Junior Member
I have a Ram 1500 4.7 4X4 which I bought with an engine tick and which has 207,000 KM (124,000 Miles). The body and interior are excellent and I got the truck for a good enough price that I can put whatever money I need into the engine if I have to and it is still a good value. I have tried many things to resolve the tick, and at this point I am ready to pull the engine because that is the only way I can really see what is going on. Before I do that I was hoping for more experienced people to advise if there is anything else I should do first.
Here is a video of the tick, which has not changed regardless of the repairs I have made:
To diagnose the issue I have counted the cadence of the tick which seems to be about 1/4 of engine RPM. This told me that the tick appeared to be somewhere in the valve train. The oil pressure seems to be normal. There are no engine codes. It is difficult to tell if this sound is coming from the top or bottom, or the left or right. I have a mechanic's stethoscope and no matter where I put it I can hear the tick. It definitely sounds louder from the bottom end, on the driver's side right on the back frost plug. So if it is in the valve train, shouldn't the sound be louder on the top end and on one side?
If I rev the engine up to 1500 - 2000 RPM and hold it there the tick reduces dramatically. When I let my foot off the gas, the tick comes back as it starts to approach lower RPM and idle. The tick does not change with engine temperature.
What I have checked and done so far:
1) Looked for smoke - there is no smoke at any time when the truck is running, startup or warm
2) Oil and coolant look normal
3) Looked at all the spark plugs and they look normal
4) Took compression test (130 - 150 PSI each cylinder, which seems low but I did not disconnect the fuel and take the test with the throttle wide open which I think I am supposed to do)
5) Removed the accessories
6) Changed all lash adjusters and rocker arms - There was some movement but everything actually seemed to be pretty good. There is no movement in anything now
7) Looked at (but did not mic) the cams and they looked fine. If these are only slightly outside of spec would it cause a tick, or would lobes worn enough to cause a tick be obvious?
8) Replaced the complete timing set including chains, gears, and adjusters; adjusters were at max and there was slack in the cam chains so it was time anyway
9) Replaced the exhaust manifolds - both were warped up to 3/16 inch and were leaking based on the burn marks on the gaskets
10) Checked the flex plate and bolts and all appeared normal
11) Removed the coil wires one at a time on each cylinder to see if there was any change in the sound (to diagnose if it is a rod bearing) and there was no change
12) Even though I did not think it was a rod bearing, I removed the oil pan and removed all of the connecting rod bearings. They looked brand new and after plasti-gauging them they were all easily within tolerance. Manipulated the connecting rods and there did not appear to be any up and down movement in the wrist pins. There was still cross hatch on the cylinder walls I could see from underneath.
What I am planning to do next:
1) I bought a cylinder leakage tester kit to see if everything is tight in the cylinders/heads. This should hopefully tell me if I have ring or valve problems (piston slap or valve seats?) If this is normal
2) I will mic the cam lobes to make sure they are within spec
3) Can this possibly be anything to do with the reluctor ring? (Would that not tick at engine RPM if it was rubbing somehow?) How can I check this?
4) Pull the engine and tear it apart - look at the heads, main bearings, connecting rods, pistons.... I can't do much more with the engine in the truck. I could pull the heads, but at this point I think I will just rebuild the engine.
If it was a valve guide would the valve seal not be bad and should I not see that in the spark plug condition?
Can it have anything to do with torque converter or bearings (I don't think so since it does this in park and does not change if I put it in gear)
Can the starter bendix somehow be causing this? (doubtful)
Does this sound like it could be a main bearing issue? I don't think so but perhaps... Would a main bearing sound better at 1500 RPM? No oil pressure problems?
Anything else I have not considered?
Also, if anyone has a line on new connecting rod bolts... They are torque to yield but seem to be discontinued from Mopar with no after market replacements...
Thanks very much. I appreciate greatly any insights anyone can provide.
Here is a video of the tick, which has not changed regardless of the repairs I have made:
To diagnose the issue I have counted the cadence of the tick which seems to be about 1/4 of engine RPM. This told me that the tick appeared to be somewhere in the valve train. The oil pressure seems to be normal. There are no engine codes. It is difficult to tell if this sound is coming from the top or bottom, or the left or right. I have a mechanic's stethoscope and no matter where I put it I can hear the tick. It definitely sounds louder from the bottom end, on the driver's side right on the back frost plug. So if it is in the valve train, shouldn't the sound be louder on the top end and on one side?
If I rev the engine up to 1500 - 2000 RPM and hold it there the tick reduces dramatically. When I let my foot off the gas, the tick comes back as it starts to approach lower RPM and idle. The tick does not change with engine temperature.
What I have checked and done so far:
1) Looked for smoke - there is no smoke at any time when the truck is running, startup or warm
2) Oil and coolant look normal
3) Looked at all the spark plugs and they look normal
4) Took compression test (130 - 150 PSI each cylinder, which seems low but I did not disconnect the fuel and take the test with the throttle wide open which I think I am supposed to do)
5) Removed the accessories
6) Changed all lash adjusters and rocker arms - There was some movement but everything actually seemed to be pretty good. There is no movement in anything now
7) Looked at (but did not mic) the cams and they looked fine. If these are only slightly outside of spec would it cause a tick, or would lobes worn enough to cause a tick be obvious?
8) Replaced the complete timing set including chains, gears, and adjusters; adjusters were at max and there was slack in the cam chains so it was time anyway
9) Replaced the exhaust manifolds - both were warped up to 3/16 inch and were leaking based on the burn marks on the gaskets
10) Checked the flex plate and bolts and all appeared normal
11) Removed the coil wires one at a time on each cylinder to see if there was any change in the sound (to diagnose if it is a rod bearing) and there was no change
12) Even though I did not think it was a rod bearing, I removed the oil pan and removed all of the connecting rod bearings. They looked brand new and after plasti-gauging them they were all easily within tolerance. Manipulated the connecting rods and there did not appear to be any up and down movement in the wrist pins. There was still cross hatch on the cylinder walls I could see from underneath.
What I am planning to do next:
1) I bought a cylinder leakage tester kit to see if everything is tight in the cylinders/heads. This should hopefully tell me if I have ring or valve problems (piston slap or valve seats?) If this is normal
2) I will mic the cam lobes to make sure they are within spec
3) Can this possibly be anything to do with the reluctor ring? (Would that not tick at engine RPM if it was rubbing somehow?) How can I check this?
4) Pull the engine and tear it apart - look at the heads, main bearings, connecting rods, pistons.... I can't do much more with the engine in the truck. I could pull the heads, but at this point I think I will just rebuild the engine.
If it was a valve guide would the valve seal not be bad and should I not see that in the spark plug condition?
Can it have anything to do with torque converter or bearings (I don't think so since it does this in park and does not change if I put it in gear)
Can the starter bendix somehow be causing this? (doubtful)
Does this sound like it could be a main bearing issue? I don't think so but perhaps... Would a main bearing sound better at 1500 RPM? No oil pressure problems?
Anything else I have not considered?
Also, if anyone has a line on new connecting rod bolts... They are torque to yield but seem to be discontinued from Mopar with no after market replacements...
Thanks very much. I appreciate greatly any insights anyone can provide.