Re: Water pump

Posted by TxGoat On 2024/5/21 7:29:32

I would loosen the fan belt and check for any indication of loose bushings. The bushings may wear out of round due to the pull of the fan belt, so look for ANY wobble in any direction. If you can feel any slack in the bushings when working a fan blade forward and back by hand, the bushings are probably too loose to use. I tried several times to pack a pump with worn bushings, to no avail. After a few tens of miles, at most, it was leaking again. A pump with good bushings and a shaft in good condition will not leak if properly packed and adjusted. As noted, an adjustment or two may be needed immediately after re-packing, and it's a good idea to run the fan belt a little on the loose side for a hundred miles or so with with a new or rebuilt pump. The packing nut is not to be tightened, but only just snugged up. Tight packing can conceal loose bushings, so loosen the packing nut a little when checking for loose bushings. NEVER run the engine without water or other coolant in the system, unless you take the fan belt off. Doing so will burn out the packing.

Worn bushings will allow the fan to wobble slightly forward and back at the blade tips, and may allow the entire fan to move straight forward and back for a fraction of an inch. Test with the packing nut backed off a little and the fan belt slacked off.