Engine won't time/tension

[Fraser.J.]

Right I'm struggling to get my engine to time/tension correctly. It's getting rather annoying.

The engine is out the car and on a tyre/engine crane.

Using genuine Renault tools (pin, horse shoe, sprocket lock)

The engine just won't time/tension.

With all pullys loose, I've spun it round to even out any tension, then tension the belt and rotate again to even out the tension, at this point the tension goes out, I've adjusted the tension again and rotated, again goes out. Once I was able to do this and get it within the marks, only because I set it out with the marks and then rotated and it ended up within.

I then lock the inlet/exhaust pulleys before tightening everything up. Every time I have done this and come to remove the horse shoe the inlet can always rotates anti clockwise. It seems to sit like this all the time, to fit the horse shoe, even when the pullys are loose I have to turn it with the horse shoe and slip it into the exhaust cam. And it seems sprung so always pings back?

There's seems to be an issue, as using this exact method above works on another engine half an hour before?

Any ideas/advice?

 

[Ph1 Tom]

@Phase1sr had tension issues and needed a larger pulley

 

[Mr R.]

That was only because my head was skimmed mate.

 

[MicKPM]

But this is a simple job, all you need are the correct tools... mwhahahaha!

Sorry, but that's what the FB groups would have you believe and when "we" argue the point, we're scare mongering money grabbers. The trick to timing these engines bob-on is all experience. What you're finding is a common problem and it's due to the torsional effect which goes thru the floating assembly when you torque the fixings... is there any slack in the setting points on the cams at all? As you "tighten" the fixings the camshafts naturally try to turn with the fixing (which is why we need to grip them firmly in place). If there is any "slack" in the setting point or if the grip tools aren't correctly secured the cams can advance slightly (we're talking minutes not degrees). Then, when you remove the setting tools and rotate the engine by hand, you find the minor inaccuracy is exaggerated and that stops the tool sliding back in as below:

For reference, how it should be after you've rotated the engine:



Mick

 

[Fraser.J.]

But this is a simple job, all you need are the correct tools... mwhahahaha!

Sorry, but that's what the FB groups would have you believe and when "we" argue the point, we're scare mongering money grabbers. The trick to timing these engines bob-on is all experience. What you're finding is a common problem and it's due to the torsional effect which goes thru the floating assembly when you torque the fixings... is there any slack in the setting points on the cams at all? As you "tighten" the fixings the camshafts naturally try to turn with the fixing (which is why we need to grip them firmly in place). If there is any "slack" in the setting point or if the grip tools aren't correctly secured the cams can advance slightly (we're talking minutes not degrees). Then, when you remove the setting tools and rotate the engine by hand, you find the minor inaccuracy is exaggerated and that stops the tool sliding back in as below:

For reference, how it should be after you've rotated the engine:



Mick

I know this ain't an easy task!

I'm just struggling to get it right having had a few attempts.

I can't even get the cams to line up like that when the pullys are lose, they always seem sprung out of position? I have to physically rotate the inlet cam with the horse shoe to slip it into the exhaust cam, to me this isn't right?

With everything lose, tbc pin in, horse shoe in, firmly locking in the pullys before tightening, it always springs it of position before I even rotate the engine! Never mind the tensioner playing funny buggers

 

[MicKPM]

These are 100% new fixings aren't they Fraser? Old camshaft fixings don't like to be reused and seem to bite up long before torque is achieved.

 

[MicKPM]

Give me a call on the office line and i'll talk you thru it - 01159721501

Mick

 

[neil a]

What engine Fraser your old one rebuilt or did you end up using cams and parts from the cup engine?
Your always going to have some tension on the camshaft as it is compressing valve springs but sounds like you have more than normal.

 

[franx]

^^ this is what we also found out redoing mine, we noticed this pressure from the lifters ?