Mechanics

TAPPET NOISE

Toyota Corolla

Toyota Corolla-1997; 88,000 miles; 1.6L-4FE engine: A couple of weeks back, I got the tappet valve seals replaced due to mild smoke from the exhaust at high acceleration. Since then, the engine (tappet) has become noisy. There is no noise at all when the engine is cold. The noise comes on as soon as the engine is warmed up and remains. The seals were replaced by pressurising each cylinder with compressed air, without removing the head. At that time, engine oil & filter was also replaced. The workshop replaced the engine oil again. No use. Then they added " RESTORE" - engine oil additive. No use. The noise is worrying. It has been a very smooth car all along. What should I do next?
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Tercel
January 29, 2007.



They may have the timing belt/chain off a notch. Have them check it. If the belt is off a notch it will make a lot of valve noise.

Tiny
Mmprince3000
Jan 30, 2007.
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.

Tiny
Tercel
Jan 30, 2007.
Could be the lifters, also could be it was not shimmed properly. I would have them check the clearence between the cams and the shims (usually a cold engine), and verify the belt is not off.
Bottom line is that if they did the repair and it made noise afterword, there is a very logical chance they did something incorrectly.

Tiny
Mmprince3000
Jan 30, 2007.
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.

Tiny
Tercel
Jan 30, 2007.
You need a special tool to compress the shims and a pick tool to pull them out.
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.

Tiny
Mmprince3000
Jan 30, 2007.
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?

Tiny
Tercel
Jan 30, 2007.
If it is making valve train noise, as in an improperly shimmed valve train, then you will cause undo wear to the cam.
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.

Tiny
Mmprince3000
Jan 30, 2007.
Thank you very much. Will do these and will keep you posted. Thanks again!

Tiny
Tercel
Jan 30, 2007.
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!

Rasmataz
Jan 31, 2007.
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![/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!

Tiny
Tercel
Jan 31, 2007.
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