Humvee loud rattle problem solved (presumably)-Power Steering issue

[Hoefler]

When first start up with cool engine, no rattle. After engined hits 200 degrees, the rattle would start. Sounded like a metal heat guard on exhaust rattling. Looked every where but couldn't pin point it.
After enough head scratching, I finally determined that it must be the belts on power steer pump and or generator. Figured the belt were slipping so I picked up a bottle of belt dressing which helped for about ten minutes. At least it got me to the root of the problem.
While adjusting the power steer pump, I noticed it flexed out a bit which caused me to crawl under the truck only to discover the lower bolt that secures the pump bracket to engine was sheared off.
This left only the upper two bolts to hold the pump in alignment.
I took the pump with bracket off from below the truck. Tight fit but it will drop down if you unbolt the sway bar.
I simply drilled a hole through the broken boly and pounded a flat blade screw driver into the hole, backed out the fugitive threads (mine was a 1/2-UNC bolt). Picked up a grade 8 bolt 1 1/2" long with new lock washer and re-assembled.
Will tackle the bleed procedure in the morning.
Check your bolt on the bottom of this bracket-two on top and one easily seen by crawling under the vehicle.
Pete

 

[erasedhammer]

When first start up with cool engine, no rattle. After engined hits 200 degrees, the rattle would start. Sounded like a metal heat guard on exhaust rattling. Looked every where but couldn't pin point it.
After enough head scratching, I finally determined that it must be the belts on power steer pump and or generator. Figured the belt were slipping so I picked up a bottle of belt dressing which helped for about ten minutes. At least it got me to the root of the problem.
While adjusting the power steer pump, I noticed it flexed out a bit which caused me to crawl under the truck only to discover the lower bolt that secures the pump bracket to engine was sheared off.
This left only the upper two bolts to hold the pump in alignment.
I took the pump with bracket off from below the truck. Tight fit but it will drop down if you unbolt the sway bar.
I simply drilled a hole through the broken boly and pounded a flat blade screw driver into the hole, backed out the fugitive threads (mine was a 1/2-UNC bolt). Picked up a grade 8 bolt 1 1/2" long with new lock washer and re-assembled.
Will tackle the bleed procedure in the morning.
Check your bolt on the bottom of this bracket-two on top and one easily seen by crawling under the vehicle.
Pete

Are you talking about the tensioning bolt for the PS pump?

 

[Hoefler]

No. There is a pivot bolt that screws into the cylinder head. The tensioning lockdown bolt is just beneath that. The third bolt (the one that I found to be broken) is seen when you are under the truck. If that bolt is broken, it allows the power steer bracket to flex.
Pete

 

[Hoefler]

Finished up and can report rattle is gone, belts running way smoother and the bleeding procedure to be simple.
Its not a two man job to tighten belts. It was however before I had found the broken bolt.
Pete

 

[Hoefler]

Rattle is back. Sounds like ball bearings in front of engine. Water pump bearings are free of play. Need help here.

 

[Bravojmc]

Rattle is back. Sounds like ball bearings in front of engine. Water pump bearings are free of play. Need help here.

Pete,
Let's try to eliminate one system and go onto the next.
If you have the engine running and you turn the steering wheel does it make any difference in noise?

 

[Hoefler]

I would appreciate the help.
Steering back and forth feels normal until the last few degrees of wheel turn were the steering wheel turns harder. The noise-not a whine-does not seem to change when doing this. I have done the, run engine, turn full right, shut of engine for 15 minutes, then repeat to the left. Did this a couple of times. I do notice that when I first start after sitting over night, the rattle takes longer to start up-like maybe 3 to 5 minutes.
Of note-this truck has a mile marker winch that runs off the power steer pump. Nothing looks hacked-truck looks factory original with no rube goldberg stuff.
I did not that the fluid in pump looked a little discolored-not frothy but sirred up.
Pete

 

[Bravojmc]

I would appreciate the help.
Steering back and forth feels normal until the last few degrees of wheel turn were the steering wheel turns harder. The noise-not a whine-does not seem to change when doing this. I have done the, run engine, turn full right, shut of engine for 15 minutes, then repeat to the left. Did this a couple of times. I do notice that when I first start after sitting over night, the rattle takes longer to start up-like maybe 3 to 5 minutes.
Of note-this truck has a mile marker winch that runs off the power steer pump. Nothing looks hacked-truck looks factory original with no rube goldberg stuff.
I did not that the fluid in pump looked a little discolored-not frothy but sirred up.
Pete

Pete,
Both of my humvees have a little bit of resistance at full lock that's normal.
do you have a 3' section of steel or alum rod that you can use as a stethoscope to different parts on the engine?
Ive used this technique a lot over the years. As for the power steering powered winch... I don't have any experience with this system. Any way your hearing the Cady valve noise?
also. Anyway to get a video clip of this noise?

 

[Hoefler]

I will grab a piece of aluminum on my way out tonight. Will give it a go and also get video.

 

[Hoefler]

Looked at the fluid in the power steer pump before and after-its not frothy or bubbly. Used an aluminum tube to ear-cadilac valve, power steer pump and water pump are not making the noise. Its seemingly more around the fan. Its not the little crimped bracket that holds shroud back-checked that and added silicone.
When I grab the fan, it does not free wheel. I grabbed the unit in front of fan center-it feels free and not worn. What the crap.

 

[Hoefler]

I notice that the unit in front of fan moves with rotation of fan a bit. I am wondering that the noise might be coming from fan hub insides. Like a pawl that is loose or dragging.

 

[Bravojmc]

Hard to hear but it sounds like belts slapping...?

 

[Hoefler]

The sound is more metallic.
I have been doing more investigating (fiddling) with her. Good, because I am now learning this truck and how cool the mechanicals are.
I found the thermal switch that operates cadilac valve was not working. My fan never cycled out-it was always back toward engine. Wrapped on the electrical component next to valve as well as pushed the four wires going into it-down. Got the fan to cycle out. Watched as the hose from valve flexed, pushing fluid to kysor which made the fan cycle away from front of engine. The rattle changes a bit when cycling.
Took the truck out for a little drive-was quiet, then got real loud again. Parked it in driveway and let it idle-the rattle eventually went away with only occasional rattle. Let it run and pushed and lifted on four wires at electrical switch to cycle fan.
Got quiet again.
So, I cranked the steering wheel all the way left hard. When it came on the stop, it rattled again, but faint. Let the wheel go and no noise.
Used a wooden stick to listen to water pump, benny and p-pump. All I can hear is wiring and not rattle.
I am thinking its the fan clutch. Its firm with no play. When I stand at front of truck, I can hear rattle out of the top hood vent which places the noise at the fan clutch.
Maybe there is air trapped in the clutch oil.
I am going to let it sit over night with hopes more air comes out.
Bravojmc-thanks for following this thread and chiming in. I much appreciate it.
Pete

 

[snowtrac nome]

look at the alternator mounting bracket those were prone to breaking one or all three bolts holding it on along with the rear curley q bracket between the rear lower pivot piviot point and the exhaust header also loosen up the alternator check the pulley and rotor for noise while the belts are loose

 

[Hoefler]

I will check that today.
Pete

 

[Hummer Guy]

I will check that today.
Pete

Did you ever find what the issue was?