Cam Chain Tensioner


SaskGT

GT Owner
Dec 24, 2013
46
Looking for information on the hydraulic cam chain tensioner actuator. I removed the two from my engine yesterday (to remove the heads) and noticed that one side could easily be pushed in and out by hand against the internal spring but the other would not. It was solid, as I played with it for several minutes it finally started to work to push in and out. Each time it would move a small amount and a tiny amount of oil would come out until it finally had a full range of stroke in and out. Is there an internal check valve in these tensioners or is something wrong? I don't want to replace good parts but this is much too important if questionable.
Also what is the sealant on the back side that seals them to the block?
Any info would be appreciated.
 

Xcentric

GT Owner
Mark II Lifetime
Jul 9, 2012
5,199
Myakka City, Florida
Do you have the workshop manual?

Tensioners require a vice to compress and retaining clips to hold the plunger in.

Any damage to the sealing bead...including permanent compression...requires new tensioners.
 

SaskGT

GT Owner
Dec 24, 2013
46
I do have the manual. It does not cover the actual operation of the tensioner. One tensioner I could push in by hand, the other seemed like it was locked solid at first then eventually would compress by hand (after many tries).
There is no visible damage to the sealing bead, however not sure about the permanent compression.
 

RALPHIE

GT Owner
Mar 1, 2007
7,279
I do have the manual. It does not cover the actual operation of the tensioner. One tensioner I could push in by hand, the other seemed like it was locked solid at first then eventually would compress by hand (after many tries).
There is no visible damage to the sealing bead, however not sure about the permanent compression.
I would give a call to the GT Guy, Kendall and/or Shadowman. Or, any of the engine modifiers (Hennessey, Accufab, etc). Or PM Soroush.
 

Lorenzo

GT Owner
Mark II Lifetime
Dec 28, 2008
625
U.S.A.
I would call John Mihovetz at Accufab. You would be hard pressed to find anyone more knowledgeable then him when it comes to a Modular Ford motor. IMHO.
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,270
Minnesota
These are the plastic or steel ones??? the steel ones do not go back in due to special retainers that keep them from loosing up, so if one pushes in with out using a pick there is a problem with it. Stick cars shock the timing system more then auto cars do and this is why ford made these, but they can possible over tighten in a certain serious race car app too. The plastic ones are just an internal spring and should push back with your hand but it difficult with either! We modify the steel ones to get rid of the ratchet system and shim them so there never can be any slack or very little..
 

SaskGT

GT Owner
Dec 24, 2013
46
These are the plastic or steel ones??? the steel ones do not go back in due to special retainers that keep them from loosing up, so if one pushes in with out using a pick there is a problem with it. Stick cars shock the timing system more then auto cars do and this is why ford made these, but they can possible over tighten in a certain serious race car app too. The plastic ones are just an internal spring and should push back with your hand but it difficult with either! We modify the steel ones to get rid of the ratchet system and shim them so there never can be any slack or very little..
They have a steel piston and cylinder with a plastic case.
 
Aug 25, 2006
4,436
Yes a check valve and I would encourage replacing them while you have the motor apart.

I would also encourage upgrading them; John at AccuFab would be the direction I would point you.

Takes care

Shadowman
 

SaskGT

GT Owner
Dec 24, 2013
46
Yes a check valve and I would encourage replacing them while you have the motor apart.

I would also encourage upgrading them; John at AccuFab would be the direction I would point you.

Takes care

Shadowman
I have ordered new ones from Ford, do you recommend a modification to the Ford tensioners or an aftermarket upgrade?
 
Aug 25, 2006
4,436
Yes; I encourage a chat with John and consider upgrade cam chains and tensioners. As I recall, the primary chain would remain OEM however the 2 cam to cam chains and tensioners would be different.

All the best

Shadowman