I have a 1997 F-250 with 7.3L diesel engine. Yesterday I started my truck and heard a loud squeal and light thumping under the hood. I raised the hood but could see nothing wrong. My initial thinking is that the water pump bearing is getting ready to go, although there is no visible leak and there is no play in the fan. All the internal gauges look good and there is not noticable decrease in performance or power. I don't want to drive it while it's making that noise so I'm trying to see if any of you more knowledgeable gentlemen can give me some recommendations.

Also, my truck was sold to me as a '97 but the plate in the door jamb says it was manfactured in December of 1997. Wouldn't that actually make it a '98?

Moby

 

Maybe you have a belt tensioner pulley, idler pulley, alternator or a vacuum pump headed south.
Remove the belt to see if the noises go away. With teh belt off you can Spin the pulleys by hand to check them out.

 

If you have a 1998 OBS then you are the only person in the world that has one as Ford never made a 1998 OBS to my knowledge.

You might consider pulling the belt off and checking every inch if it the check all of the pulleys for freedom of movement.

You never said if the engine was still running when you were under the hood and if so could you still hear the noise/bumping.

Rog

 

cat?.......

 

the '97 model year carried over into '98 while ford was finishing up the '99 NBS, so trucks manufactured in what would normally be a '98 model year are actually a '97... and the '99s started production early as well i believe... as did the '08s

 

The engine was still running and, no, it was not a cat.

 

Its all those Horses trying to get out! lol

I would do what Cuda and kawa said to do and see if the noise is still there with the belt off.

 

X2 what the other fella,s are saying if you still can,t find the bad bearing or what not you can try a mechanics stethoscope with the belt on and truck running they work surprisingly well.

 

I'm gonna try what Cuda and kawa said; remove the belt and play with the pulleys to see if I can duplicate the noise. Anyone have any diagrams showing the proper routing of the belt so I can put it back on without screwing it up?

 

 

or this one.
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Accessory Drive Belt, 7.3L Diesel Engine
1 Generator
2 Belt Idler Pulley
3 A/C Clutch Pulley
4 Vacuum Pump
5 Power Steering Pump Pulley
6 Crankshaft Pulley
7 Water Pump Pulley
8 Drive Belt Tensioner
9 Drive Belt<O></O>

 

In my trials with belts and pulley's every time a pulley decided to go south the belt did not run straight causing it to fray on the rubbing side and boy did it make a heck of a sound-like a cat dying. The belt would not be frayed much at all. after finding the culprit if your belt is frayed it will need to be changed.

 

Jose Bond,
Where do you come up with all of these schematics? They're Great.

I tried to Rep ya but they said that you have too much love as it is.

Rog

 

........................

Thanks Roger, I know about that

Sincerely
J. BOND.

 

You guys are all great. I'm gonna pull that belt off this evening and try to find the culprit.