2004 4.0 timing chain rattle, chgd tensioners-different rattle

[adinini]

2004 Explorer, 4.0 2WD had a slight timing chain rattle only on start-up.
I changed the rear hyd tensioner. It starts fine, no rattle on start-up. However, about ten seconds at idle the rattle re-appears and sounds even worse now. I re-installed the old tensioner but the rattle is still there(idle), about ten seconds after start.
I changed the front tensioner too, but it didn't stop. I drove it around for awhile hoping it needed oil pressure build-up, but still the same.

(didn't use crush gasket on rear tensioner, No oil leaks, oil level good)

What did I do wrong???

Any suggestions?

Thanks!

 

[2000StreetRod]

replacing hydraulic tensioners

Unfortunately, for the last couple of years the new hydraulic tensioners (even from Ford) seem to have weaker springs than the old ones being replaced. I doubt you did anything wrong. The spring pressure only matters when the oil pressure is low. Once the engine is running and the oil pressure is normal the hydraulic pressure in the piston should be keeping the chain taught. If a cassette guide is broken the slack side of the chain will still be loose even when the piston is fully extended. The following link may be helpful: Timing chain rattle resolution process - SOHC V6

 

[adinini]

Thanks StreetRod

I put the old part back in hoping it would go back to its original condition, but it didn't.
I changed the rear tensioner but the rattle/pinging is coming from lower front engine.
I also changed front tensioner but no change.

 

[2000StreetRod]

another possibility

Harmonic balancer failure

 

[adinini]

No sqeaking, sounds like marbles in a can

 

[cross6]

Unfortunately, for the last couple of years the new hydraulic tensioners (even from Ford) seem to have weaker springs than the old ones being replaced. I doubt you did anything wrong. The spring pressure only matters when the oil pressure is low. Once the engine is running and the oil pressure is normal the hydraulic pressure in the piston should be keeping the chain taught. If a cassette guide is broken the slack side of the chain will still be loose even when the piston is fully extended. The following link may be helpful: Timing chain rattle resolution process - SOHC V6

Sorry to hijack, but I've seen it mentioned in other threads how the newer ford tensioners are weak and some people have had them collapse and stay collapsed.

I compared a cheapo chinese time kit from ebay with a new motorcraft tensioner and the chinese one had much more spring tension.

Do you think we should start using non-ford tensioners like cloyes or somebody?

 

[adinini]

Yes, the spring on the new tensioner was very weak...same or less than the old one I took out.