4.0 SOHC rear chain tensioner anyone fix one that did not leak?

[robs2002explorer]

OK, Got an 02 Explorer 4.0 SOHC. Got a leak from that stupid cam chain tensioner on the passenger side. I have 100K miles and have no chain noises at all. I did a million searches and all of them said that when they replaced this it leaked. Was anyone sucessful installing this without a leak? It drips on my new driveway now and prevents us from using the AC when driving due to the smell.
I took it to a supposed good mechanic and he found out that it was not the valve cover but this tensioner and he was afraid to touch it...claimed all hell would break loose if you took it out....Thanks much!

 

[boominXplorer]

Its probably the valve cover that is leaking, they start leaking from the back corners.

 

[wbrudi28]

i just replaced both my tensioners. i bought them on eBay, Ford OEM parts. was like 150 bucks for the pair. one goes in the front and one goes in the back. They need to be removed with some extensions and a breaker bar, just e careful not to slip and mar the engine block because these tensioners don't use a gasket. simply metal on metal. then when you install the new ones, you need to torque them down to 59 ft/lbs. mine leaked at 59 so i set my torque wrench to about 62 and then they stopped leaking.

edit: the passenger side (rear) tensioner is accessible thru the wheel well. take the wheel off and peel back the plastic fender well. it's behind spark plug #6 i believe

 

[Tyleryac]

If you are replacing the tensioners getting the correct torque spec is very important. When Ford did mine they weren't tourqued correctly and they rattled until they were re-tourqued.

The leak sounds more like a valve cover like boominxplorer said.

 

[CDW6212R]

The external tensioners do have a seal behind them, it's a thin folded metal crush washer. Look at a spark plug that uses a gasket, it's a similar appearance but thinner.

Don't install one without the seal. Mine were OEM Ford parts when I did it in 2005, the seals were included then. Now I gather it's rare to get the seal with the tensioner. I suggest being very careful with the old parts, and save the old seal in case it's needed again. Regards,

 

[EXPLORER04]

If you need a new metal o-ring for the tensioner they are part number XU2Z6M252AA

 

[wbrudi28]

+1 forgot one of the tensioner a uses a thin crush washer. All the research I did pointed towards just one crush washer, the other tensioner didn't use one. I used the old one on my new OEM tensioner

 

[CDW6212R]

They both should have one, a seal. Leaving one out is likely going to make a leak.

 

[Tech By Trade]

You can reuse the washer, it just requires more torque. Have a look at the service manual for the specific torques. If you need a washer they are around 15 bucks each from the stealership.