Cam gear endfloat "fix"

 Russell made me ring to add to the camshaft gear wheel.

The plan was to make it flush with the end of the cam gear shaft.

It is now bonded to the gear and the endfloat when measured on the engine is 0.05mm (with some of the float taken up with the lube) The tolerances are 0.02mm to 0.1mm.

I think its a Quaife gear but I can't find an adjustable version "on line" so don't know why the shaft is not right.
We tried to fit it in a combination of ways and this mod is the only solution that seemed to be right.

The previous owner had to grind down the bumps for the water pump bolts as they would contact the cam gear adjuster bolts. 3 of the bumps were ground down enough to break through.

minor repair attempted.

camshaft endfloat

While I was trying to determine the cam spec - I had noticed that there seemed to be excessive endfloat.

The thrust plate would not hold the cam in place and the only thing stopping the cam gear from grinding into the block was the camshaft end bearing core plug.

Eventually it was noticed that the cam gear shaft was the same diameter as the chamfered spacer.
The cam gear was removed (for the first time) and it was then possible to see the evidence that the original cam gear had a much larger diameter shaft.

If I reversed the cam gear on the cam then I was able to prove I would have the correct amount of endfloat.

As I haven't removed the gear or thrust plate until now - I haven't lost or misplaced anything. Note the Chamfered spacer is on the wrong way round in the photo.

I will try to make a bush to fit or find a suitable thrust washer.

camshaft identified

The left cylinder head was installed.
(note the bigger valves!)

The rocker assembly ultrasonically cleaned and fitted.

With the valve gaps set - then the difference in measurements relative to valve versus cam follower becomes more obvious.

It now looks more like the cam is a fast road piper cam.

The cam was set to full lift on the inlet of piston 1 by measuring start and finish point of the dwell angle (12 degrees) and setting the crank angle to halfway in between.

The cam is then disconnected from the sprocket and the crank set to 112 degrees ATDC,
The cam then reconnected and new yellow alignment dots added (will drill later)

Monitoring the valve and crank angle now shows a close approximation to the fast road cam spec 24-68 68-24







references
http://www.pipercams.co.uk/pipercams/www/tech_camshaft_installation.php
http://www.pipercams.co.uk/pipercams/www/tech.php

What cam is it!

I don't know what the camshaft is, I suspect a fast road cam.

It has a "P" and number 401 and 112.
I hope it means Piper cam
0.401" lift & 112 degrees inlet full lift.
But probably wrong.

I started by measuring the camshaft with the dial guage on the cam followers.

I got a 60 degree overlap and 173 degree duration.

I set the camshaft to be in the middle of the overlap at TDC






Then checked the timing again against the crank.
Measurements then didn't seem quite so obvious.

I began to worry I had a full race cam.
Thought best to install the cylinder head and measure on the rockers.

Tomorrow... maybe.

bottom end rebuild part one

                              Hurrah! the bearings have arrived.

Time now to install the crankshaft.

Note the areas where the crank has been smoothed.
Is this the result of damage being repaired or balancing?
There doesn't appear to be any other damage to the casing or bearing caps.

I used lubriplate on all the surfaces and storage oil as a coating.

Pistons were next to be installed.
Honing marks were still visible on the bores, so it hadn't been run for long before it was abandoned.

I might find out why later when I try to start it.



Now I'm stuck again as the camshaft sprocket doesn't have any markings on it. and I failed to notice when I pulled it apart. The camshaft is non standard. maybe a fast Piper road cam. Markings on the end are P 401 / 112. I will measure it tomorrow and attempt to set the timing from theory.