Having replaced timing gears both by removing the radiator and not, I'd suggest leaving the radiator in place. Access to the gears is easier by removing it, but then you've got to deal with the radiator and all that coolant that invariably spills all over the place while draining, refilling, etc.

As you mention, it's hard to see so I marked the timing marks with a sharpie before starting so I could tell without a doubt if they were lined up right from my limited vantage point either under or above the area of interest. I always lave a little mirror in my toolbox for shenanigans like this. This photo is of a set of steel gears so yours will look different.


To block the gears from turning while loosening and tightening nuts I jammed rags in the teeth. Leaving it in gear is scary because you likely have the front jacked up. Turning nuts means turning wheels which could roll the car off the stands in the front. The crank pully is generally not tight enough for this to be a concern but the cam nut usually is. By the way, that nut fits a, I believe, 36 mm socket.

Getting the fiber gear off can be a real pain and I have never managed to do it without breaking it into pieces. Be sure to cover the little opening into the oil pan to keep stuff out of there. Also, this is a good time to remove the oiler nozzle and give it a cleaning.

Below is a photo of the last timing gear I pulled. I was lucky enough that I was in the garage when the car finally quit running completely. Note the lach of several teeth.

Lastly, a failing gear sounds terrible and makes your heart sink but it's honestly not that big of a deal. I wonder how many cars have been abandoned due to a rod knock that only needed a new timing gear.


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Justin 66 122E
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