How is the valve lash/clearance adjusted on a 97 Tercel? One source suggested shims but most others said screwdriver and wrench adjustment. The only concern was to do them while the engine is hot. Can anyone clarify?
Thanks.
Jim
How is the valve lash/clearance adjusted on a 97 Tercel? One source suggested shims but most others said screwdriver and wrench adjustment. The only concern was to do them while the engine is hot. Can anyone clarify?
Thanks.
Jim
If it's only doing it at start-up, cjances are it's the valve stem seals.
I have had a Twin Cam Corolla for 19 years and never had to adjust the valves!
Check this out before you remove anything. And, on my Supra, replacing the oil with Castrol High-Mileage seems to have resolved this problem.
The subject on your post suggest that your 1997 Tercel is burning oil on startup. Adjusting valve lash will not affect oil consumption.
With DOHC and 4 valves per cylinder, my guess is that valve lash is adjusted with shims, and yes, valve lash should be adjusted while the engine is hot.
In my eagerness to simplify my message, maybe I oversimplified :(
First thing I noticed was that oil consumption between changes had increased but not hugely. Then I noticed the engine at idle had become noisier although none of the other members of the household agree with me about that. Then I noticed the smoke at startup. I figured the noise was associated with the valve gear and linked that to the burning oil in the morning. Hence my oversimplified question :) So I guess I'm looking at worn valve stem seals for the oil consumption and smoke. Any clues about the noise on this engine?
If the smoke is only apparent at startup and the smoke is blue-grey color, then leaking valve stem seals are a likely cause.
Noises are difficult to diagnose without actually hearing them first hand. If the noise is coming from under the timing cover, you may be hearing the timing belt slapping, especially if it has been more than 60,000 miles since the timing belt was replaced.
"Ray O" wrote in news:849a3$46082e3e$44a4a10d$ snipped-for-privacy@msgid.meganewsservers.com:
Valve lash is adjusted **COLD**.
The only time you would EVER adjust valves with the engine hot is on pushrod engines. Pushrods lengthen with heat, so you have to adjust the clearances when they're at their longest.
"Jimbo" wrote in news:1174939013.333582.276400 @o5g2000hsb.googlegroups.com:
Your engine uses shims on top of the valve spring buckets. Adjustment is a time-consuming job, but rarely needs to be done if the oil has been changed regularly.
Check the clearances before thinking you need to adjust them.
Adjust **COLD**!
And if you're burning oil on startup, your valve guide oil seals are shot. This is usually due to insufficiently frequent oil changes.
I can appreciate why that may be the case, however, my Corolla 4AC requests the motor, warmed to normal op temp.
That is one reason. How were those push rods operated?
Hammo
Hmmm .... timing belt? The previous owner told me it had been replaced and that was just about 60,000 miles ago. Maybe its time to do that anyway.
I believe that the timing belt replacement interval is 60,000 miles under severe conditions - frequent short trips, idling, towing, etc. That said, the timing belt may not be the source of the noise.
Hammo wrote in news:C22ED1C0.1E5A9% snipped-for-privacy@aapt.net.au:
What's your source for that?
All the 4A engines I've even known have required valve lash be set cold. Toyota did not even give hot clearances, as far as I can find.
By lifters riding on the camshaft, of course. Adjustment was by screw and locknut at the rocker.
So I did an oil and filter change using high mileage oil. First start up was smoky but not excessively so. This morning, the exhaust appeared less smoky and less blue than the last couple of weeks. Only other factor is weather is much warmer this week than previously. Engine still sounds noisier than usual but I haven't had time to look into that.
hey guys, i had found this new website
So what was the problem regarding your car?
The service manual for the vehicle. "Once vehicle has reached operating temperature....."
A typo?
Hammo
Hammo wrote in news:C24336C1.20F80% snipped-for-privacy@aapt.net.au:
Maybe not. Does the 4AC have shim-type adjusters or screw-and-locknut?
Any pics in that manual? Is this a Haynes or Chilton manual?
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