JX cambelt tension

[superdes]

I've have just replaced the head on my JX and am putting a new belt and tensioner on whilst it's relatively accessible.
I don't have the special tool to check the belt tension but was wondering whether there is a rule of thumb people use to get the tension about right?
I have currently tensioned it so it can be easily twisted 45 degrees but won't quite go to 90 even with some force. Does this sound right? If anything it seems a bit loose but I don't want to go too tight and knacker my bearings.
I may have to bite the bullet and get the proper tool but I'd like to get it up and running over the holidays without the belt flying off or damaging something else.

[colinthefox]

That's about right.

[superdes]

That's good to know. I'll turn the key with a bit more confidence now. Thanks

[California Dreamin]

90 degrees on the longest length...but then you need to make sure the crank is turned so the opposite side is tight and all the slack is on that longest side.
The result you're after is that 'once the engine is up to temperature' this free play is all but gone (the belt gets tighter as the block & head expand)
However, factor into this slight initial stretching of the new belt.

Martin

[superdes]

Cheers Martin. I have the van back up and running now with the belt tension set as in my previous post. This seems to work well and I've run it with he timing cover off and it's not flapping all over the place. I will however see what it's like when the engine is hot, as per our advice.

[California Dreamin]

Over tensioned belts tend to 'sing' as in wur - wur - wur - wur noise (when hot)

Martin