1966 318 Poly timing gear

[bob32268]

A friend was talking to me tonight and mentioned that his 67 Pontiac (400 motor) jumped time due to the nylon teeth on the timing gear breaking off. I had the same problem back in the 70's also (with a GTO). I was wondering if my 66 Coronet with a 318 Poly engine came from the factory with an all steel timing gear or did MOPAR also use the nylon teeth timing gears also??
Tks,
Bob32268

 

[Jerry Hall]

I don't know about the 318 Poly, but original timing gears in 383 and 440's had nylon or some kind of fiber gears. I took one out of a tired 383 a while back that was in nearly perfect condition.

 

[Vaanth]

A friend was talking to me tonight and mentioned that his 67 Pontiac (400 motor) jumped time due to the nylon teeth on the timing gear breaking off. I had the same problem back in the 70's also (with a GTO). I was wondering if my 66 Coronet with a 318 Poly engine came from the factory with an all steel timing gear or did MOPAR also use the nylon teeth timing gears also??
Tks,
Bob32268

The 1966 318 Poly was originally equipped with a steel camshaft timing gear (sprocket).

The aluminum gear with nylon teeth was introduced as a running production change in late 1965 on big block engines, except Hemi. The small block, except 340, and slant six engines started using the aluminum gear with nylon teeth in 1968. The last year for the 318 Poly engine was 1966 in the US and 1967 in Canada.

The following image shows the introduction in the 1966 Service Highlights:

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[bob32268]

The 1966 318 Poly was originally equipped with a steel camshaft timing gear (sprocket).

The aluminum gear with nylon teeth was introduced as a running production change in late 1965 on big block engines, except Hemi. The small block, except 340, and slant six engines started using the aluminum gear with nylon teeth in 1968. The last year for the 318 Poly engine was 1966 in the US and 1967 in Canada.

The following image shows the introduction in the 1966 Service Highlights:
View attachment 2075839

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Thanks a lot Vaanth, now I don't have to tear the front of my engine off.
Bob32268

 

[pnora]

Thanks a lot Vaanth, now I don't have to tear the front of my engine off.
Bob32268

Are you the original owner? If not its possible that the original gear and chain were replaced. Just saying.