DIY: Valve Clearances - 4G15 and 4G93

donki

donki

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4G15 and 4G93 factory valve clearance specs:

-Adjust when the engine is hot, and when rockers are not rocking.
-Rotate engine by hand so cylinder 1 is at TDC of compression stroke.
-Adjust the clearances as follows to the specs below:
Cylinder 3's intake
Cylinder 4's intake
Cylinder 2's exhaust
Cylinder 4's exhaust

Intake when hot: 0.2032mm
Exhaust when hot: 0.254mm

When Cylinder 4 is at TDC of compression:
Cylinder 1's intake
Cylinder 2's intake
Cylinder 1's exhaust
Cylinder 3's exhaust


4G15:
Intake when hot: 0.2032mm
Exhaust when hot: 0.254mm

4G93:
Intake when hot: 0.200mm
Exhaust when hot: 0.300mm


Dont mess it up, cause if theyre too tight, you're car will sound like a v6 with a cam, or if its too loose it will tick like an old VN
References:
valveclearanceqb1.gif

(Intake cold 0.1016mm, Exhaust cold 0.1778mm, if you want to experiment and try these with the engine cold)
 
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Re: Valve Clearances - 4g15

So what your saying is.......... do it to tight so it sounds like its better then it really is? :P
 
Re: Valve Clearances - 4g15

th0m0mx83 said:
So what your saying is.......... do it to tight so it sounds like its better then it really is? :P
Click to expand...

Yes :troll:



Too tight will mean the valves dont fully close, pumping fuel and air into the exhaust, and back into the intake. Sounds cool-ish, but it will burn out your valves and thats a bad thing
 
I did this :thumbdown: first time adjusting valves haha soooo regretful lol car ran fine i touched them to get rid of what sounded like a noisy lifter but instead i made it worse lol :crazy:
 
95Luke said:
Are the 4g15 specs listed here are correct for the dohc 16 valve 4g15 as well?
Click to expand...

I'm not sure, i do know that the 0.200mm and 0.300mm is a relatively standard valve clearance for any engine, so it would be a good starting point. You can then closer or open the gap if the car is too noisy or lumpy afterwards.
 
So doing it this way means that you don’t have to make each cylinder tdc one by one? Once cyl 1 is tdc I can adjust other cylinders even if their not tdc? (Within the instructions of course)
 
Yep. Pretty much just ensure the relevant valve is not in contact with the cam lobe and you’re sweet.

Base circle part of cam and you’re good to adjust. Itll make sense when youre there
 
Currently doing this able to adjust cylinder 4 just fine however I can’t adjust cylinder 2s exhaust or cylinder 3s intake as they’re in contact with the cam?
 
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