2F Timing Gears - when replace?? (1 Viewer)

[berntd]

Hello all,

My manual is inconclusice here...

Is the timing gear on the camshaft made of Novotex (plastic type stuff)?

Does it need to be replaced at a certain interval?
Is it a big job?

I ask because my old dad just said that this motor seems based on an old american design. If so, it will eventually break the teeth of the cam gear unless it is replaced at certain intervals to prevent this. He also said that it is a big job to replace this gear as the camshaft has to come out and the gear is pressed on?

Anyone have input please?

Kind regards
Bernt

 

[cruiser_guy]

I don't know for sure but I've heard the older motors do have a plastic type gear. I know I have a new cam and a new crank gear here if you're interested.

 

[matt.mcinnes]

2F timing gears are metal, the 3F and 3FE had nylon cam gears so I suspect it has been replaced in the past already.

They all use the same size gear size though.

Early 2F and late 2F the later on the left. Both have a metal cam gear

 

[Trollhole]

If it looks like this I'd replace.

Vever heard of teeth breaking off.

Maybe that was for straight cut gears?

 

[matt.mcinnes]

I think he means the smaller gear from the first post.

But as your pic shows the later gear has a composite bond that can crack after time too.

If your replacing, then best done as the pair in my opinion and in metal.

 

[amaurer]

Has anyone ever seen that composite bond fail? Its loaded primarily in shear, I have to imagine its going to take a lot before it lets go, even cracked... ?

 

[Trollhole]

I've heard of a couple people on Mud have them fail. That being said I would doubt it would for a long time. The motor my picture was from had at least 250k of miles on it.

 

[Rhinoliner]

My 78 2F cam gear has the rubber strip in it and I wasn't aware of it being a potential problem when I installed my new cam.

When I finally got far enough along in my restoration to start the engine it had a knock coming from the timing cover. I had to go half way back into the engine to install a new cam gear and that fixed my problem. You can't really see anything wrong with my old gear.

If I ever have to put a new cam in one of these engines again, it will definitely get a new gear also.

my $.02

 

[subzali]

From:
https://forum.ih8mud.com/40-55-series-tech/138196-truck-running-rough-not-driveable-help-2.html

 

[berntd]

Hello,

Thanks for that. Steel is good and I will leave in peace then.
We were under the impression that the gears were made from Novotex (reddish bakelite type of material) like in the old US engines.

My 2F is a 1981.

Kind regards
Bernt