cam belt tensioner

I've read everything I could find on this board and on TurboFord and there seems to be disagreement about the function of the cam belt tensioner. When I got my 88 TC a few months ago I discovered that the tensioner spring was installed backward on the pivot bolt. I dicided to "fix" it. I assumed, incorrectly it seems, that the tensioner should provide tension while the engine is running, so, after turning the spring around and (finally) getting it on the pegs I lossened the hold-down bolt in the slot and fired it up. The belt promptly skipped several teeth and the car won't run. So, after the fact, I read the Haynes manual and discovered that one is supposed to pry the tensioner into position and lock it down. If that's the case, what is the tensioner for? Some previous posts here also seem to suggest the the tensioner should be locked down, while others indicate the opposite. Please help this newby understand.

After proper tension is applied to the belt with the tensioner somewhat loose, the tensioner is supposed to be locked down. That's the way everything I've seen says to set it up, which makes me wonder what the heck the spring is for. I suppose that it's to set the correct initial tension, and that's it.

Interesting note: the whiz-bang tensioner that Esslinger makes has no spring, and they say it's not necessary; we'll see when I put mine on.

HTH.

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Be Cool,

Joe

JR's Place - My 87 TC

The spring is to assist in putting the tensioner in a position to apply tension to the belt. I think the springs get weak with age (and maybe heat cycles). Sometimes they need to be "helped" a bit to achieve proper tension. Especially if the back side and the head are rusty. However you don't want to over tension the belt as this will affect bearing wear in the crank.cam and aux shaft bearings