Have heard a light knocking (not really metallic, more of a plastic sound) from front of engine for past few days - was intermittent, would hear it mostly when cruising to a stop light. I had poked around and looked at the radiator fan, belts, etc, but nothing looked out of order or felt loose. We were on the highway this morning going around 55mph and the knocking sound really started accelerating. Began to pull over on the shoulder when the knocking sound stopped and then the dashboard lit up with the brake and oil light. Car ran fine for the few seconds it took me to pull over and even reverse on the shoulder (knocking sound was gone). Popped open the hood and found what looks to be the water pump pulley with a large crack. Belts somehow managed to stay in place through all this. While we're in there replacing the pulley and belts does it make sense to replace the waterpump? Anything else that we should address?
Broken Pulley
- Thread starter rogermarcon
- Start date
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Check fan blades and backside of radiator for damage. Check for stuck, wobbly, or rough feeling water pump shaft, alternator, fan clutch, all pulleys/idlers.
Could you post up more photos of any damage including the fan pulley
once it's off the engine?
Could you post up more photos of any damage including the fan pulley
once it's off the engine?
- Thread starter
- #3
Yes i think water pump is on my list, but if it failed i wouldve thought i’d see leaking coolant somewhere. I think the belts might have been on there a little too tight and this is the result
- Thread starter
- #4
Yes ill get a couple more pictures when it’s pulled apart
Never seen that before. Bummer.
- Thread starter
- #6
An update - put new pulley on and found a slight wobble. The waterpump was slightly bent - not sure if it was the cause, or a result, of the pulley failure. Waiting for a new waterpump to come in and then should be good to go.
really wierd - stamped/formed steel part - normally crack proof.
(1991 FJ80 @235k miles) This exact same thing happened to me about a week ago and I'm pretty sure it was the pulley connected to the water pump. After spending the day putting on new brake pads I was driving around testing them out and all of the sudden this loud intermittent popping sound started coming from the front end of the engine compartment. It wasnt metallic and constant, it was occasional. At first I thought something might have gotten stuck in the fan blade, but I wanted to be sure so I immediately pulled over and got a tow. When I got it home I noticed the pulley was really wobbling with the motor on. But when the pulley would find its "center" and not wobble the noise would go away. Then it would go off track again and the loud popping would begin. So I pulled off the belts and saw that I could easily wobble the pulley by hand. No bueno. So after some research I concluded that it would be best to just suck it up, replace the pump and do some PM while I had the front end pulled apart. I attached some photos so you can see the condition of the pulley.....I'm still waiting on parts to come in the mail.
Some lessons learned.
Disclaimer: My truck has a lift so its pretty easy to get underneath and work from the bottom up, also, I have NWTI bumper with a flat "step" so its convenient to stand on that and get deep inside the engine bay. Your rig will be different so you have to find what works for you.
1. Remove the battery and tray, it's worth it for the extra space
2. The bottom left (Passenger Side) Water Pump hose can be easily removed by coming underneath the truck, there is a bolted clamp that secures the hose to the engine compartment that may be difficult to see from the top down, once that is removed the hose should budge. You do not need to remove the Power steering pump or AC bracket.
3. There are 4 studs that secure the water pump to the engine. You will need to remove the bottom 2 on the left side (passenger side) of the water pump before the water pump can be easily detached. You don not need to remove the small guide pulley. Some have referred to the "double nut" method to remove these studs, however, because of the tight spacing I found it easier to just purchase a set of stud extractors (not the conical shaped one, its too big)
4. Purchase an extra long double ended 12mm / 14mm flex head ratchet and a breaker bar
5. You will need to drain the radiator. There is a petcock on my bottom right (Drivers side) of the radiator. The petcock did not have a nipple to attach a hose. I re purposed the hose from my coolant overflow reservoir to drain into a 5gal gerry can. Still made a mess, had to basically hold the hose against the petcock for 15minutes to drain. Arm was very tired. Even after this coolant will pour all over the ground once you detach the water pump.
Good luck and hope this helps
Some lessons learned.
Disclaimer: My truck has a lift so its pretty easy to get underneath and work from the bottom up, also, I have NWTI bumper with a flat "step" so its convenient to stand on that and get deep inside the engine bay. Your rig will be different so you have to find what works for you.
1. Remove the battery and tray, it's worth it for the extra space
2. The bottom left (Passenger Side) Water Pump hose can be easily removed by coming underneath the truck, there is a bolted clamp that secures the hose to the engine compartment that may be difficult to see from the top down, once that is removed the hose should budge. You do not need to remove the Power steering pump or AC bracket.
3. There are 4 studs that secure the water pump to the engine. You will need to remove the bottom 2 on the left side (passenger side) of the water pump before the water pump can be easily detached. You don not need to remove the small guide pulley. Some have referred to the "double nut" method to remove these studs, however, because of the tight spacing I found it easier to just purchase a set of stud extractors (not the conical shaped one, its too big)
4. Purchase an extra long double ended 12mm / 14mm flex head ratchet and a breaker bar
5. You will need to drain the radiator. There is a petcock on my bottom right (Drivers side) of the radiator. The petcock did not have a nipple to attach a hose. I re purposed the hose from my coolant overflow reservoir to drain into a 5gal gerry can. Still made a mess, had to basically hold the hose against the petcock for 15minutes to drain. Arm was very tired. Even after this coolant will pour all over the ground once you detach the water pump.
Good luck and hope this helps
From the pictures, it doesn't look like anything is wrong with the pulley. Did it fracture like the OP or were the fan clutch nuts just loose, or is the bearing in the water pump shot?
Yes, I mispoke. Not the pulley itself but he part on the water pump that spins around which the pulley attaches to. My guess is the bearings were worn. The fan clutch nuts were tight however the clutch itself was sort of seized. I managed to clean and lubricate it and now it rotates. Do you see the dark, powdery, metallic dust on the pump where the pulley sits and also inside the pulley? It isnt carbon build up or oil, it was fresh and dry like ground coffee, Im assuming thats where the bearing had worn down.
At this point you should be purchasing a new Aisin water pump (WPT-029) or Toyota part# 16100-69255; a new Aisin fan clutch (FCT-049). The 3FE fan clutch is no longer available from Toyota, but Aisin is the OEM.
Also carefully inspect the plastic fan blade for hairline stress cracks. After 30 years of use, they can fracture.
- Thread starter
- #13
I also saw this dust on my truck. Was on the blades of the fan and the pulley itself. You can kind of see it in the first picture of the tread
For what its worth, I have plenty:
absolute-wits-end.com
80 Series 3-Groove Water Pump Pulley
80 Series 3-Groove Water Pump Pulley (WPP-1)