1997 Toyota Corolla Tappet Noise
Thanks v much... It has a timing belt, I had the timing checked with a strobe light - it was around 10 deg and we adjusted it back to around 7 to 8 deg by moving the distributor. No change in the noise. Is that sufficient or should I look for timing marks or something on the gears or any other method? I heard that some of the hydraulic lifters could be making the noise. Is this possible & could they be replaced? This happened immediately after the seals replacement.
Bottom line is that if they did the repair and it made noise afterword, there is a very logical chance they did something incorrectly.
Bottom line is that if they did the repair and it made noise afterword, there is a very logical chance they did something incorrectly.[/quote:a904b24366]
I too feel that they mixed up the shims. Is it possible to check the clearance in the hydraulic type? Is it done the usual way? Can I do it myself? They said that there is no need for any adjustment - it adjusts by itself.
The shims have a tolerence between the cam and the shim. With engine at TDC#1 you can check the clearence on #1 intake and exhaust. There is a procedure in the Haynes manual or the factory service manual.
You can check the clearence yourself, but if you do not have the special tool and a supply of various shims (thickness), it would be tough, or time consuming at best.
Assuming they got the wrong shim on, you would have to measure each intake and exhaust clearance, the thickness of each shim and compare to the factory specs, then put the proper shim in the proper place.
I would insist they do it, since from what I've read it wasn't making valve train noise until after they installed new seals.
The shims have a tolerence between the cam and the shim. With engine at TDC#1 you can check the clearence on #1 intake and exhaust. There is a procedure in the Haynes manual or the factory service manual.
You can check the clearence yourself, but if you do not have the special tool and a supply of various shims (thickness), it would be tough, or time consuming at best.
Assuming they got the wrong shim on, you would have to measure each intake and exhaust clearance, the thickness of each shim and compare to the factory specs, then put the proper shim in the proper place.
I would insist they do it, since from what I've read it wasn't making valve train noise until after they installed new seals.[/quote:388cc839d7]
Thanks! I don't have the special tools, so I will go back to them to get it done... I have 2 more questions: (a) Is there any harm if I leave it like this say for a couple of months? and (b) How can/should I check the lifters at the same time?
I am not sure there is a procedure for checking lifters, other than replacement, in which case you have to remove the camshafts.
That is the reason I mentioned the timing belt, if it is off a notch is will make a definate rattling noise and advancing or retarding the timing would not help since only one cam may be off.
Get a Haynes manual and check to make sure the belt is on correctly and use the procedure to check valve clearance. The only thing it would cost you is the cost of the Haynes manual and a valve cover gasket.
I am not sure there is a procedure for checking lifters, other than replacement, in which case you have to remove the camshafts.
That is the reason I mentioned the timing belt, if it is off a notch is will make a definate rattling noise and advancing or retarding the timing would not help since only one cam may be off.
Get a Haynes manual and check to make sure the belt is on correctly and use the procedure to check valve clearance. The only thing it would cost you is the cost of the Haynes manual and a valve cover gasket.[/quote:303061e29f]
Thank you very much. Will do these and will keep you posted...Thanks again!
Maybe they clogged-up the oil passages to the head or block and its not being lubricated BTDT. If this is not the case-these 2 are partners in crime lifters and Camshaft.
One goes the other follows.
Good Luck!
One goes the other follows.
Good Luck![/quote]
They did the seal replacement w/o opening the head - by using air pressure through the spark-plug holes to hold up the valves. In such as case, is it possible to clog up the oil passages? Your 2nd point is what someone at the OEM recommended:- replace the camshaft and the lifters. But that is expensive!
Open the valve cover and check whether the oil is making it all the way up there. Check your oil pressure with a pressure gauge start from there-to rule out a clog pick-up screen and a sloppy pump
Open the valve cover and check whether the oil is making it all the way up there. Check your oil pressure with a pressure gauge start from there-to rule out a clog pick-up screen and a sloppy pump[/quote:098143f6b8]
Thanks. Btw, how safe is it to start the engine with the tappet cover opened? Will it spray or splash the oil all over the place? The exhaust manifold cover is just beside it... If its ok, it would be a great way to see if proper lubrication is taking place...
Open the valve cover and check whether the oil is making it all the way up there. Check your oil pressure with a pressure gauge start from there-to rule out a clog pick-up screen and a sloppy pump[/quote:fa5073c9b1]
Thanks. Btw, how safe is it to start the engine with the tappet cover opened? Will it spray or splash the oil all over the place? The exhaust manifold cover is just beside it... If its ok, it would be a great way to see if proper lubrication is taking place...[/quote:fa5073c9b1]
No nothing is gonna jump out there to hit you-just get plenty of rags beside it. its nothing compared to a push rod engine. Give it try.
My guess they overtighten the valves and worn out the lifters and camshaft before the oil got to it. There's such thing as cold and hot valves adjustment-by using a feeler gauge.
Great addition to this thread! Please feel free to help out on the site whenever it can add information that will help.
Best, Ken
Suggested Repair
Have the shop recheck cam timing-belt alignment using the timing marks, not just distributor timing. Measure cold cam-to-shim clearances and correct any mixed or incorrect shims. Verify oil pressure and that oil is reaching the valve train. If the cams were removed, reload the split cam-gear spring preload before reassembly, since unloaded gears can rattle like noisy lifters. Do not leave incorrect valve clearances uncorrected, as they can wear the cam.
Conversation Summary
A 1997 Toyota Corolla 1.6L developed warm-engine tappet noise immediately after valve stem seals were replaced with the head on, using compressed air. Oil changes and an additive did not help, and adjusting distributor timing did not change the noise. Experts advised checking whether the timing belt was off a notch, measuring valve clearances in case shims were mixed, and verifying oil pressure and oil delivery to the head. Continued noise from incorrect clearances can wear the cam. A later contributor explained that Toyota split cam gears must be spring-preloaded after cam removal or they rattle like noisy lifters.
