Inertia seat belts

Andrew Wiggins

Andrew Wiggins

New Member
I've just had my 73 V8 MOT'd and a comment was passed by the tester that the front seat belts weren't locking under sudden tension. Sure enough he's correct, but just tilting the mechanism slightly all is well. Without hurling myself down the road and violently testing is this correct with these original 40 year old Wingard belts or do I bin and buy new?
 
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I believe they work differently to standard inertial reel belts in that the locking mechanism isn't on the movement of the belt but in the inertia of the reel itself in that there is a pendulum inside which swings and locks the reel. which explains why tilting it works too.

So your MoT tester is wrong.

In theory this is a superior design allowing easier movement with no accidental locking, the downside being you can't test it very easily.

I would ask some of the gurus here to confirm before relying on my comments but I remember being told this.
 
tester has overall say though one can appeal using due process. in short if tester finds its not working as expected he can rightly fail it. any appeal would need to show tester was checking correctly e.g. sudden pulling having the inertia mechanism work and 'lock ' the belt up .so yanking fast in same direction as worn is correct test/check. thus where a belt is drawn through B post vertically ..this ought to be same direction as when worn /impact effect.
some types do indeed have a spring loaded weight using pendulum effect and direction ( vertical or otherwise) therefore is irrelevant. though I would presume ALL belts have to travel from floor mount via B pillar support before going diagonally across driver/passenger into buckle .
 
I've taken them off the car, retensioned the belt retraction springs and lubricated the mechanism. All movements are free and as I have already observed any tilt and they lock up, but sat in the vertical they move freely. Hopefully Peter is correct and if it comes to the crunch they work.
Thanks for the replies.
 
Hi Andrew.
It's not part of the test to check if the Belt locks when pulled.
Only locking part checked is the stork itself.
Those belts you have work under heavy braking if not damaged.
Clive.
 
Clive, thanks for the info. The tester did only mention he thought they weren't working-not a fail as you said.
Anyway did go out and test them and they do work! Now to replace the rear pads for the retest next week.
 
Andrew Wiggins said:
I've taken them off the car, retensioned the belt retraction springs and lubricated the mechanism. All movements are free and as I have already observed any tilt and they lock up, but sat in the vertical they move freely. Hopefully Peter is correct and if it comes to the crunch they work.
Thanks for the replies.
Click to expand...
Andrew
What condition were the internals like?
The fact mine have never been a problem and I take them for granted
Perhaps its something we all should be doing i.e. pull apart and re grease etc.
My P6 have the originals - but still working fine .
 
I remember fitting inertia reel front seat belts to my Austin 1100 when I was a tallow youth of 20 years old. Cars at that time did not have them fitted as standard and I thought that it would be a good idea to fit them to my car. The type that I fitted apparently had a large ball bearing in the bottom and that jammed and took the tension when activated. Perhaps the tester should pay more attention to that area of the setup? ;)
Peter
 
The belts and the mechanisms are in very good nick for 43 years old. I cleaned with a healthy jet of WD40 and left lightly oiled. To be fair not much crud came out.
These are the Wingard safety belts and have the pendulum weight rather than the spring and steel ball. The retraction springs were a bit lazy. ( three extra turns sorted that out ).

Next job. Having fitted Spiyda RVI to RVC conversion board, recalibrate the tachometer.
 
I understood the locking mechanism should be left dry , no lubricant as it attracts dust and can then not work correctly.
 
I had an argument with a muckanic many years ago about the very same thing. They work on the inertia of the car, not the seatbelt reel.

Can be a right pain if parked facing downwards on a steep hill when trying to put them on :)
 
I just had the exact same comment from my MOT tester about my seat belts. I have just had them apart and sure enough they have a weight on a pendulum which causes them to lock when the car is under deceleration (hopefully). They gave me a ticket anyway. I will have to point out this thread next time.
 
I have tested my seatbelts by travelling down the road and pulling on the belt whilst braking. The mechanism works fine and catches even at a fairly modest deceleration. It gives me peace of mind that if anything unfortunate does happen I should be protected.
 
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