rear shoulder belt question

[burgermeister]

I just ordered a replacment 3-point used rear seat belt for my 88 coupe. The belt does not unwind - the inertial latch catches it, no matter how slow I pull. The junkyard says it must be installed in the car to unspool. Is this true, or just a bunch of BS? I'd hate to take the rear deck apart for no reason - time is a precious commodity for me.

[bpoteat]

Sounds like bunk to me, but I am as far from a seatbelt expert as you could get. I just don't see how mounting it will make the internal mechanism be any different.

[burgermeister]

Bunk indeed.

I messed around with the seatbelt again for a bit - and, it does unspool just fine out of the car...just as one would think.

Happily, this was not the junkyard recommended by our host (the recommended one didn't carry the seat belt).

I'll figure this Porsche parts thing out sooner or later... (or go broke trying )

[burgermeister]

I believe I was in error.

Maybe not Bunk after all.

I'm not sure how or why this is, but the extremely cantankerous seatbelt appears to work just fine once installed. The previously very smooth seatbelt from the car (with partially cut webbing, which is the reason for replacement) no longer unspools except with a LOT of fiddling. I asked a friend who is a safety and crash engineer at GM, and she suggested the belt had to be mounted in just the right orientation and held very rigidly for the inertial latches to work properly.

Also, uninstalled belt seems to unspool better once some of the belt is already extended.

Go figure.

[petrolblue83911]

When I replaced the front belts on my 83 a few yrs back, the new belts I bought from out host would not unwind at all until installed. I thought they may have been defective at first, but they worked perfectly once on.