Renault diesel (J8S) Timing belt woes

[derskine]

Whilst the 18 is off the road I thought I might as well change the timing belt, it's just about hit the interval anyway.

Reading the manual it suggests I need to measure the frequency of the belt once tensioned and it's to match 65hz.

The tool it suggests to use is £600.

Has anyone dealt with this and have a better solution, will a tuner app on my phone work?

It's the 2068cc N/A engine but I imagine the turbo engine is much the same.

[mouseflakes]

I've read the same line for testing my Saxo Dizzler belt - it requires a 'Seems' meter or summert like that to test it? I've only ever had timing chains on my cars before the Saxo so it's all like voodoo to me.
 
When I checked around on various forums most folks seemed to think the 'quarter turn' test was sufficient and seem to have been using it for years.
 
(This guy doesn't approve by the way - you can tell just by the expression on his face...)
 

[Rusty_Rocket]

As above, just set it by feel. Get a 2nd opinion if you're not 100%!

[gordonbennet]

Following OMGCHG outside oil leak on my 2068 engined Savanna i stripped and rebuilt the engine, and slipped a new belt at the time, never did anything any different to usual of the time, marked the relevent pulleys (sod timing kits who needs one) and tensioned by twisting the longest run by 1/4 turn to slightly tighter than the old one.

 

Lovely engine that was, typical French design though, everything crammed on one side and room for a party the other.

[derskine]

Decent, that's what I wanted to hear.

I had my concerns as I read somewhere if the head gasket blows, you can't get the head skimmed or the valves will contact the pistons.

I'm familiar with the 1/4-1/2 turn test, and will do exactly as "gordonbennet" did.

[Pillock]

You have to test the resonant frequency of the new belt?!

 

Zat is, how do you say, bloody stupid.

[derskine]

Yep, I did a little research and a few points were brought up, ie different manufacturers belts being composed differently.

[Sigmund Fraud]

Yes, Mr.Renault's engines are so advanced* that you are expected to use NASA equipment to set the cambelt tension...

 

Rubbish ! As already said, use the quarter turn test and it should be fine.

[twosmoke300]

Ducati recommend the same tension measuring method . Us mere mortals see if a 6mm Allen key fits between belt and tensioner.

[cort16]

What's the 1/4, 1/2 turn test?

[derskine]

Yes not sure why I said half turn! For some reason I thought I'd previously tensioned belts at a half turn, but thinking about it, that's fairly ridiculous.

It's 1/4 turn, and thats the way I've always done it, just getting my fractions mixed up...

[Rusty_Rocket]

The trad way of getting the timing belt about* right* was being able to twist it a quarter turn on its longest stretch. 

This is fine on old engines like Pintos and other correctly engineered engines but not really applicable on nasty, needlessly complicated modern stuff with dozens of pulleys and tensioners. There definitely is a 'feel' to a correctly tensioned belt but I'm not sufficiently articulate to describe it.