m923a2 engine noise

[winterton1]

just stated to hear a low clunking/rattling noise at the front of my 5 tons engine. i can only hear it when its idling. Could this be the fan clutch or vibration dampener going bad?? Any ideas??

 

[M35A2-AZ]

I had a M932A2 that did that also, I was thinking it was the idler pulley.

 

[simp5782]

just stated to hear a low clunking/rattling noise at the front of my 5 tons engine. i can only hear it when its idling. Could this be the fan clutch or vibration dampener going bad?? Any ideas??

Take the belt off the engine from around the crank and see if the noise goes away. If it does you will be looking for something on that is belt spun. Alternator,fan,waterpump. If it is there you need to get a stethoscope and try to determine where it is. May be in the timing gears too.

 

[Elijah95]

The only issue I’ve ever had with that noise is it coming from my fan clutch, at low idle especially in gear it can be prone to this awful rattle clanky noise so like they said I’d take the 5 minutes to pull the belt and fire it up to listen

 

[winterton1]

5 ton noise

thanks for the ideas!! I will take the belt off and listen. did not think about the fan clutch because I had a bad one on a vehicle once - but it simply froze up. hope its that simple!

 

[74M35A2]

The fan blade bolts back out of my fan repeatedly on my a2 8.3L May be the same issue you have.

 

[winterton1]

5 to noise

i will check those bolts
as well...thanks!

 

[simp5782]

The fan blade bolts back out of my fan repeatedly on my a2 8.3L May be the same issue you have.

Have you removed your front engine mount bolts into the block to inspect that they are tight or not stripped out? Some of the offroad users with the 8.3 end up having bolts like that and the crank bolts back out due to a bad or broken front mount and it breaks the bolts off in the block and or cracks the timing cover due to the vibration. I actually have one to do this weekend that did just that. Gotta drill em out

 

[74M35A2]

Mine is for sure the fan. Only happens when the fan turns on, and fan blade is loose. Tightened twice so far now. Getting false tightening feedback because internal threads are rusty. Need to remove clutch, re-tap holes, then install new bolts with new lock washers, and it should hold.

 

[simp5782]

Mine is for sure the fan. Only happens when the fan turns on, and fan blade is loose. Tightened twice so far now. Getting false tightening feedback because internal threads are rusty. Need to remove clutch, re-tap holes, then install new bolts with new lock washers, and it should hold.

I meant a weak front mount causes vibration and lets bolts back out

Sent from my SM-G965U using Tapatalk

 

[winterton1]

bolts all tight. turned out to be the fan clutch. thanks for all the help.

 

[Swamp Donkey]

Mine is for sure the fan. Only happens when the fan turns on, and fan blade is loose. Tightened twice so far now. Getting false tightening feedback because internal threads are rusty. Need to remove clutch, re-tap holes, then install new bolts with new lock washers, and it should hold.

I'd just swap the engine instead. Don't you have one sitting on a stand somewhere...

 

[Jericho]

on your loose bolts drill the heads and install 20 thousands stainless aviation safety wire easy as pie WORKS

 

[WillWagner]

I'd just swap the engine instead. Don't you have one sitting on a stand somewhere...

Ouch!

 

[Steelreaper80]

Older post but I need some advice. I had the classic fan clutch rattle so I ordered the rebuild kit and the new style shutterstat. I had a shop install both. Fan clutch sounded fine at first but started getting progressively louder. 1500 miles later it is the worst is has even been. I took a peak and it is metal on metal on the alternator side and about an 1/8th inch clearance on the other. The front of my engine looks like it is covered in glitter from metal shavings. Is there a way to completely disable the fan just to get home? Why would it fail after a rebuild? The new one are Uber expensive. Do I just need to bite the bullet and order one? Thanks guys!

 

[74M35A2]

Sounds like the rebuild did not refresh the bearings, only the friction surfaces.

Cheapest way will be to find a used one. Though kind of rare, people do part these out. I’ve had great luck posting want ads here.

 

[Crf450x]

Older post but I need some advice. I had the classic fan clutch rattle so I ordered the rebuild kit and the new style shutterstat. I had a shop install both. Fan clutch sounded fine at first but started getting progressively louder. 1500 miles later it is the worst is has even been. I took a peak and it is metal on metal on the alternator side and about an 1/8th inch clearance on the other. The front of my engine looks like it is covered in glitter from metal shavings. Is there a way to completely disable the fan just to get home? Why would it fail after a rebuild? The new one are Uber expensive. Do I just need to bite the bullet and order one? Thanks guys!

I'd blame whoever did the rebuild. It should have been good as new after that. Super easy to source the parts and do it yourself. I actually did a small write up on it a while back but your bearings will be different, so just need to get them out and find the right ones for yours.

 

[Steelreaper80]

Here are the pics of the old fan clutch and I compared it to the new one. There was a pile of bearings on the ground where I took the fan off the old clutch to swap it to the new clutch. The front of my motor looks like my 3 year old daughter threw glitter all over my engine. Thank sweet little baby Jesus it crapped out on my while parked and not on the road. Easy fix, just expensive!

 

[M35A2-AZ]

That does look like it was about ready to go into the radiator. Good job!

 

[Bill Nutting]

Is it a bad thing when bearings fall out on the ground?
It was wise to replace it when you did. Expensive perhaps, but it could have caused other major and more expensive damage. I think you dodged a bullet! Glad to hear all is good now.