'66 L-72 Water Pump Belt

[R N.]

Hello Everyone:

Ref. '66 427 L-72 w/o ps

Looking for some help regarding the correct length belt for the water pump and the balancer pully. Quanta lists a short version (34.4") and a long version (34.8") long.

As there is no adjustment to tighten this belt how does one assure which belt to use? Can anyone share their experiences with me.

Thanks,
kurt Neiman

[Wayne M.]

Re: '66 L-72 Water Pump Belt

Kurt -- GM catalogs show # 3837810 as a 3/8"inch wide belt with length of 34-3/8". Don't know why Quanta shows one 0.4" longer, as well.

[Paul B.]

Re: '66 L-72 Water Pump Belt

Seems as though this is a "trial & error" fit. Went to go put a water pump/crank belt on my '75 A/C delete(I deleted this option!!!), GM book called for a 33.0" x 7/16" belt. Was'nt even close!!! Ended up with a 34.4" x 7/16" belt which did the trick.