Special timing idler gear on Plus models?

[douglas1947]

Last year I bought an 80 Plus model.
There were several parts missing, also on the engine.
The cam gears are there, but the cam idler gear was missing.
I have now 2 different idler gears - a standard T35 (photo left, with long stub) and a special one (photo right, with short stub).
The short stub gear has the timing marks on the non stub side. May be it is for Plus models?

I hope someone knows the gears and can tell me, what I should use in the engine.

Michael

[douglas1947]

Extra photo from the other side of the gears.

Michael

[douglas1947]

Hi all,

I still have the hope to get informations about the timing gears of the plus models.
I want to to start re-assamlbe the engine in the next days and would like to knowwhat parts to fit to the crankcase (and what bushes to make).

I will be happy for every information.

Michael

[phil1]

Hi Michael
                 Hope the photo helps, this is my mk v. phil.


[Reformat image.  28Sep22, Doug, admin]

[douglas1947]

Hi Phil,

thanks for your photo to give me help.
But unfortunatly it do not help, because it is a MK engine.

My problem are 2 different idler gears I have (difference in length of axle). The longer one is a standard MK one, the short one is unknown.

I think the front crankcase (Plus to MK) has a small difference in the timing chest, f. ex. you can not extract the cam pinions and get them out without splitting the crankcase halves.

At the moment I can do no test, because the engine is assembled.

Michael


Michael

That is the reason I would like to know, if there is a special idler for the Plus models.

[DSIM]

Michael
The Plus models have a different nose on the crankshaft as it has to accommodate the ball bearing as well as the bronze bush. The crankshaft drive gear on the standard T35 has a space between the gears but on the Plus the  drive gears butt up. Also the  PLUS GA drawing I have shows fine teeth for the cam drive and coarse teeth for the magneto drive, it also  shows the cam idler gear with short stubb towards the rear, the Plus camshaft gears also have the stubb towards the rear so the cam gears all line up and mesh correctly.
Best regards ChrisS

[douglas1947]

Chris,

thanks for the helpful explanation of the differences from standard T35 to Plus timing gears.
So I know I have to use the idler with the short stub and "reverse" timing marks.
All I have to do is to make a special bronce bush for it to fit on the stud. I will see the measures, when I reassamble the crankshaft and cams / cam gears.

Michael