I cheated on water pump installation!
artbuc
02-05-2008, 01:06 PM
RE: 99 Avalon w/ 3.0 V6 - 83k miles
Ok, I'm not sure if I am bragging or confessing on this one. Tore her open to replace timing belt and idler pulleys. Discovered water pump bearing/seal was sticking so I thought I had better replace. Bought a new NAPA TruFlow which is manufactured by Gates. Didn't have the tools and energy to remove camshaft pulleys and No. 3 timing belt cover so I used a Dremel to cut away just enough of the No. 3 timing belt cover to allow removal of water pump. After installing new pump, I closed the gap with High Temp RTV so as to maintain integrity of timing belt cover seal. It actually looks quite good.
Ok, I'm not sure if I am bragging or confessing on this one. Tore her open to replace timing belt and idler pulleys. Discovered water pump bearing/seal was sticking so I thought I had better replace. Bought a new NAPA TruFlow which is manufactured by Gates. Didn't have the tools and energy to remove camshaft pulleys and No. 3 timing belt cover so I used a Dremel to cut away just enough of the No. 3 timing belt cover to allow removal of water pump. After installing new pump, I closed the gap with High Temp RTV so as to maintain integrity of timing belt cover seal. It actually looks quite good.
Brian R.
02-05-2008, 03:12 PM
Good job. Next time you change the timing belt, let us know if it kept the timing belt clean....
RIP
02-06-2008, 06:13 PM
My first reaction, "WHAT!!!" Thinking on it, it's an option. Hope it works out for you. Keep your eyes on it. Maybe check it every oil change. Should be ok. You proved again that American enginuity can overcome anything.
artbuc
02-29-2008, 06:56 AM
RE: 99 Avalon w/ 3.0 V6 - 83k miles
Ok, I'm not sure if I am bragging or confessing on this one. Tore her open to replace timing belt and idler pulleys. Discovered water pump bearing/seal was sticking so I thought I had better replace. Bought a new NAPA TruFlow which is manufactured by Gates. Didn't have the tools and energy to remove camshaft pulleys and No. 3 timing belt cover so I used a Dremel to cut away just enough of the No. 3 timing belt cover to allow removal of water pump. After installing new pump, I closed the gap with High Temp RTV so as to maintain integrity of timing belt cover seal. It actually looks quite good.
Was telling a buddy of mine about what I did. He knows much more about car mechanical stuff than I do. He asked me why I didn't just remove the cam pulleys like I was supposed to do. I told him I tried to remove the Left cam pulley (closest to radiator) but couldn't do it because I couldn't hold pulley in place. He asked me how much the pulley moved and I told him that it moved clockwise/counterclockwise several times +/- 20 degrees. I explained that it first moved clockwise (direction when engine is running) until it went past the cam lobe so I had to rotate it counterclockwise to put it in the right spot. I did this several times before I gave up. Friend told me that rotating the cam pulley back and forth past the cam shaft lobe could have caused serious damage to my engine. I didn't argue because he does know alot; but, I can't see how that would be possible.
It is true that my shop manual makes a big deal about rotating the crankshaft clockwise only but I thought that was just to protect the timing belt.
Do you think I could have dmaged my engine by moving the cam pulley like I did? Engine seems to be running great.
Ok, I'm not sure if I am bragging or confessing on this one. Tore her open to replace timing belt and idler pulleys. Discovered water pump bearing/seal was sticking so I thought I had better replace. Bought a new NAPA TruFlow which is manufactured by Gates. Didn't have the tools and energy to remove camshaft pulleys and No. 3 timing belt cover so I used a Dremel to cut away just enough of the No. 3 timing belt cover to allow removal of water pump. After installing new pump, I closed the gap with High Temp RTV so as to maintain integrity of timing belt cover seal. It actually looks quite good.
Was telling a buddy of mine about what I did. He knows much more about car mechanical stuff than I do. He asked me why I didn't just remove the cam pulleys like I was supposed to do. I told him I tried to remove the Left cam pulley (closest to radiator) but couldn't do it because I couldn't hold pulley in place. He asked me how much the pulley moved and I told him that it moved clockwise/counterclockwise several times +/- 20 degrees. I explained that it first moved clockwise (direction when engine is running) until it went past the cam lobe so I had to rotate it counterclockwise to put it in the right spot. I did this several times before I gave up. Friend told me that rotating the cam pulley back and forth past the cam shaft lobe could have caused serious damage to my engine. I didn't argue because he does know alot; but, I can't see how that would be possible.
It is true that my shop manual makes a big deal about rotating the crankshaft clockwise only but I thought that was just to protect the timing belt.
Do you think I could have dmaged my engine by moving the cam pulley like I did? Engine seems to be running great.
Brian R.
03-01-2008, 11:59 PM
It's possible, but don't look for trouble. If it ain't broke...
Here is my explanation and it may be wrong, so anyone with a different and correct one, please jump in...
Explanation Number 1: One possible reason it is a bad idea is that your valve lifter and the cam lobe are mated and run-in together, and turning the cam in the wrong direction results in an abnormal rubbing relationship between them. They are pressed together very tightly by the valve spring and must match precisely for wear to be kept to a minimum. The cam lobe is only ground to being pressed against the lifter with the cam rotating in one direction. The lobe ramp for opening the valve is very precisely ground to do its job and the lobe and lifter are only used to one direction of rotation. Rotating the lobe in the opposite direction causes the lifter to be "opened" against the wrong side (closing ramp) of the lobe and damage to both the lobe and the lifter may result. It doesn't take much of a bad spot on either the lobe or the lifter to result in really rapid lobe/lifter wear since they are under such a high load and undergoing sliding (as opposed to rolling) friction.
You may end up replacing the cam and lifters, but don't look for trouble. As long as the engine runs smoothly, you are good. You should hear some valve noise (tapping) if a lifter has started chewing up its cam lobe. If you are lucky, none of the lobes were at a critical rotational position when you rotated the cam in the wrong direction. In this case, you are good.
Explanation Number 2: He may not know that your engine is a free-running (non-interference) engine and was worried about one of the valves coming in contact with a piston. In this case, you have no worries.
The bottom line is that it is bad form and don't do it...
Here is my explanation and it may be wrong, so anyone with a different and correct one, please jump in...
Explanation Number 1: One possible reason it is a bad idea is that your valve lifter and the cam lobe are mated and run-in together, and turning the cam in the wrong direction results in an abnormal rubbing relationship between them. They are pressed together very tightly by the valve spring and must match precisely for wear to be kept to a minimum. The cam lobe is only ground to being pressed against the lifter with the cam rotating in one direction. The lobe ramp for opening the valve is very precisely ground to do its job and the lobe and lifter are only used to one direction of rotation. Rotating the lobe in the opposite direction causes the lifter to be "opened" against the wrong side (closing ramp) of the lobe and damage to both the lobe and the lifter may result. It doesn't take much of a bad spot on either the lobe or the lifter to result in really rapid lobe/lifter wear since they are under such a high load and undergoing sliding (as opposed to rolling) friction.
You may end up replacing the cam and lifters, but don't look for trouble. As long as the engine runs smoothly, you are good. You should hear some valve noise (tapping) if a lifter has started chewing up its cam lobe. If you are lucky, none of the lobes were at a critical rotational position when you rotated the cam in the wrong direction. In this case, you are good.
Explanation Number 2: He may not know that your engine is a free-running (non-interference) engine and was worried about one of the valves coming in contact with a piston. In this case, you have no worries.
The bottom line is that it is bad form and don't do it...
artbuc
03-02-2008, 06:09 AM
It's possible, but don't look for trouble. If it ain't broke...
Here is my explanation and it may be wrong, so anyone with a different and correct one, please jump in...
Explanation Number 1: One possible reason it is a bad idea is that your valve lifter and the cam lobe are mated and run-in together, and turning the cam in the wrong direction results in an abnormal rubbing relationship between them. They are pressed together very tightly by the valve spring and must match precisely for wear to be kept to a minimum. The cam lobe is only ground to being pressed against the lifter with the cam rotating in one direction. The lobe ramp for opening the valve is very precisely ground to do its job and the lobe and lifter are only used to one direction of rotation. Rotating the lobe in the opposite direction causes the lifter to be "opened" against the wrong side (closing ramp) of the lobe and damage to both the lobe and the lifter may result. It doesn't take much of a bad spot on either the lobe or the lifter to result in really rapid lobe/lifter wear since they are under such a high load and undergoing sliding (as opposed to rolling) friction.
You may end up replacing the cam and lifter, but don't look for trouble. As long as the engine runs smoothly, you are good. You should hear some valve noise (tapping) if a lifter has started chewing up its cam lobe. If you are lucky, none of the lobes were at a critical rotational position when you rotated the cam in the wrong direction. In this case, you are good.
Explanation Number 2: He may not know that your engine is a free-running (non-interference) engine and was worried about one of the valves coming in contact with a piston. In this case, you have no worries.
The bottom line is that it is bad form and don't do it...
Thanks Brian. The engine runs beautifully when it is in Park. However, when I put it in drive and first accelerate, I hear a low frequency noise/vibration which sounds a like I have a hole in the exhaust. Then for just a second, I hear another low frequency vibration. As the engine warms up, the first noise goes away entirely. The engine accelerates great, but the noise is bothersome. Sounds like something is out of balance and briefly going thru some sort of harmonic.
In addition to moving the Left cam pulley back and forth, I also broke the crankshaft pulley bolt loose by bumping the starter with a socket/breaker bar taped against the frame. I first tried to loosen with my impact wrench. I held the wrench on the bolt for 5-10 secs before I gave up. I used the same "bumping" technique that I had used a week earlier on my wife's RX300 which has the same engine. Could I have done some damage to the crank or flywheel?
Also, the new Gates water pump has a cast iron impeller whereas the original was plastic. I'm wondering if the new water pump is a problem.
Puzzling thing is that in Park, the engine makes no noise even when accelerating hard. So, whatever is making the noise only happens when the engine is under load from driving.
Here is my explanation and it may be wrong, so anyone with a different and correct one, please jump in...
Explanation Number 1: One possible reason it is a bad idea is that your valve lifter and the cam lobe are mated and run-in together, and turning the cam in the wrong direction results in an abnormal rubbing relationship between them. They are pressed together very tightly by the valve spring and must match precisely for wear to be kept to a minimum. The cam lobe is only ground to being pressed against the lifter with the cam rotating in one direction. The lobe ramp for opening the valve is very precisely ground to do its job and the lobe and lifter are only used to one direction of rotation. Rotating the lobe in the opposite direction causes the lifter to be "opened" against the wrong side (closing ramp) of the lobe and damage to both the lobe and the lifter may result. It doesn't take much of a bad spot on either the lobe or the lifter to result in really rapid lobe/lifter wear since they are under such a high load and undergoing sliding (as opposed to rolling) friction.
You may end up replacing the cam and lifter, but don't look for trouble. As long as the engine runs smoothly, you are good. You should hear some valve noise (tapping) if a lifter has started chewing up its cam lobe. If you are lucky, none of the lobes were at a critical rotational position when you rotated the cam in the wrong direction. In this case, you are good.
Explanation Number 2: He may not know that your engine is a free-running (non-interference) engine and was worried about one of the valves coming in contact with a piston. In this case, you have no worries.
The bottom line is that it is bad form and don't do it...
Thanks Brian. The engine runs beautifully when it is in Park. However, when I put it in drive and first accelerate, I hear a low frequency noise/vibration which sounds a like I have a hole in the exhaust. Then for just a second, I hear another low frequency vibration. As the engine warms up, the first noise goes away entirely. The engine accelerates great, but the noise is bothersome. Sounds like something is out of balance and briefly going thru some sort of harmonic.
In addition to moving the Left cam pulley back and forth, I also broke the crankshaft pulley bolt loose by bumping the starter with a socket/breaker bar taped against the frame. I first tried to loosen with my impact wrench. I held the wrench on the bolt for 5-10 secs before I gave up. I used the same "bumping" technique that I had used a week earlier on my wife's RX300 which has the same engine. Could I have done some damage to the crank or flywheel?
Also, the new Gates water pump has a cast iron impeller whereas the original was plastic. I'm wondering if the new water pump is a problem.
Puzzling thing is that in Park, the engine makes no noise even when accelerating hard. So, whatever is making the noise only happens when the engine is under load from driving.
Brian R.
03-02-2008, 07:12 AM
I bet the noise you're hearing on start-up (maybe both noises) is most likely the water pump. It could be the idler pulley, but I think it is less likely. You better keep an eye on a coolant leak in that area. If the noise gets really bad or you notice a coolant leak, you better replace the water pump again.
I doubt you damaged your engine when you loosened the crank bolt.
I doubt you damaged your engine when you loosened the crank bolt.
artbuc
03-02-2008, 08:15 AM
I bet the noise you're hearing on start-up (maybe both noises) is most likely the water pump. It could be the idler pulley, but I think it is less likely. You better keep an eye on a coolant leak in that area. If the noise gets really bad or you notice a coolant leak, you better replace the water pump again.
I doubt you damaged your engine when you loosened the crank bolt.
Thanks again Brian. I replaced both idler pulleys with brand new Koyo OEM. I also suspect the water pump.
If I replace the water pump should I also install a new timing belt? I have read that once you tension/use a timing belt, even for a brief period, you should not re-install it.
I doubt you damaged your engine when you loosened the crank bolt.
Thanks again Brian. I replaced both idler pulleys with brand new Koyo OEM. I also suspect the water pump.
If I replace the water pump should I also install a new timing belt? I have read that once you tension/use a timing belt, even for a brief period, you should not re-install it.
Brian R.
03-02-2008, 10:22 PM
If the belt is pretty new, reuse the old one. Put match marks on all the pulleys and the belt and replace the belt as previously installed. Belts are cheap enough to replace it if it has more than 20K on it.
artbuc
03-07-2008, 08:34 AM
I bet the noise you're hearing on start-up (maybe both noises) is most likely the water pump. It could be the idler pulley, but I think it is less likely. You better keep an eye on a coolant leak in that area. If the noise gets really bad or you notice a coolant leak, you better replace the water pump again.
I doubt you damaged your engine when you loosened the crank bolt.
Just installed a new Toyota (factory part) water pump to replace the Gates (NAPA) Tru-Flo which had less than 1k miles on it. Also, for good measure installed new Totyota timing belt even though Gates TB also had less than 1k miles. Both noises gone. After removing TB cover I observed the Gates pump operating. You could see the TB walking in/out the drive hub. This tells me the drive hub was not exactly perpendicular to pump body, cam pulleys, etc. You could hear a low frequency whirr/groan in sync with the TB walking. The Gates pump bearing still worked smoothly but it was much harder to turn than the new Toyota pump. Also, the Gates pump is much heavier with massive cast iron impeller vs plastic and much heavier drive hub. I think some of the noise was related to the mass and design of impeller.
Called NAPA and they said they would refund my money - no problem.
PS The RTV I used to seal No3 TB cover was working great. The hardest part of the job was breaking the water pump away from the RTV!
I doubt you damaged your engine when you loosened the crank bolt.
Just installed a new Toyota (factory part) water pump to replace the Gates (NAPA) Tru-Flo which had less than 1k miles on it. Also, for good measure installed new Totyota timing belt even though Gates TB also had less than 1k miles. Both noises gone. After removing TB cover I observed the Gates pump operating. You could see the TB walking in/out the drive hub. This tells me the drive hub was not exactly perpendicular to pump body, cam pulleys, etc. You could hear a low frequency whirr/groan in sync with the TB walking. The Gates pump bearing still worked smoothly but it was much harder to turn than the new Toyota pump. Also, the Gates pump is much heavier with massive cast iron impeller vs plastic and much heavier drive hub. I think some of the noise was related to the mass and design of impeller.
Called NAPA and they said they would refund my money - no problem.
PS The RTV I used to seal No3 TB cover was working great. The hardest part of the job was breaking the water pump away from the RTV!
Brian R.
03-09-2008, 08:30 AM
Sounds like everything is under control. Good job.
micali
09-05-2009, 12:22 PM
artbuc, how hard was it to replace the timing belt? I am taking a long trip in a week and would like to change it before I go. Any advise would be nice.
artbuc
09-11-2009, 01:25 PM
artbuc, how hard was it to replace the timing belt? I am taking a long trip in a week and would like to change it before I go. Any advise would be nice.
Haven't been back to this site for awhile. If you have basic mechanical skills it is actually quite easy providing you have a Repair Manual. Go to the Camry forum and use the one that matches your engine. The installation is identical for Avalons & Camrys with the same engine. I suggest you replace the idler and tensioner bearings. Best bet is to buy a kit. The Gates and Dayco kits will probably come with either GMB or Koyo bearings which are both OEM.
Haven't been back to this site for awhile. If you have basic mechanical skills it is actually quite easy providing you have a Repair Manual. Go to the Camry forum and use the one that matches your engine. The installation is identical for Avalons & Camrys with the same engine. I suggest you replace the idler and tensioner bearings. Best bet is to buy a kit. The Gates and Dayco kits will probably come with either GMB or Koyo bearings which are both OEM.
Automotive Network, Inc., Copyright ©2025