4K Gearbox Overhauling

Early 80’s Toyota lovers do know how well their machine been servicing as their riding horse. Over the decade of wear and tear, the Toyota 4K gearbox does need servicing and worse come to worse, need a major overhauling.

Toyota Starlet KP61 belongs to Amer Asmadinar are having a gearbox malfunction when the fifth gear doesn’t seem to be engage in static nor during cruising. During the initial checking, it was suspected that the ‘mesh gear’ has worn out and need to be replace.

Jack up the car and start dismantle the propeller shaft and doing checking onto the main gearbox shaft. We found out that the shaft have quite a lot free-play and above the tolerance.  With this symptom, it’s not just a mesh gear problem, the two main bearing also need to be replace.

The Process

We haven’t had the chance of using a proper car jack, head on to Giant Store and purchase a 1 Ton Car Jack for RM110. It prove to be handy at first use tho. Not recommended if you going to use it on a regular basis. Put the car on stand and start draining the gearbox oil.

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Leaking detected.

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Mini Jack at work.


Draining all out the old gearbox oil.
Draining all out the old gearbox oil.


Draining the gearbox oil can takes some time around 5 ~ 20 minutes depending on your gearbox oil reservoir. Just let it daring over time while sipping some hot coffee.

Rusty Gearbox Oil
This is the colour of your gearbox oil after no servicing for a long period of time. Gearbox oil mixing up with rusty and oxide formation.
5 Speed 4K Gearbox
5 Speed 4K Gearbox taken out from Toyota Starlet. We’ve clean it up prior to overhauling it.
Dismantle the end side first. At this time you can check the main shaft for ‘free-play’ tolerance.
Rusty components and gears.

Front Main Bearing and Oil Seal that need to be change.
Ball bearing placement. Need to be careful not to lost it.
Worn out Oil Seal need to be change.
Arranging the components for easy checking.


The Gallery

The rest of the process can be view inside our Photo Gallery.


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