Engine

[les]

Well the flywheel saga is over so a new heading. More dismantling including cylinder head. I was interested to find a couple of threaded plugs already in the oil ways, one I’m having difficulty removing, unfortunately not in all of them have been done.

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[svenedin]

That corrosion around the water pump aperture looks quite bad. Will it affect the gasket sealing?

Stephen

[les]

Yes it needs looking at, there is an area where the gasket can seal but it could be better ! I think it will be ok.

[philthehill]

The corrosion around the bottom and sides of the water pump aperture is quite normal and does not effect anything. There is a hole through the casting/corrosion which can be cleaned up by passing a suitable sized drill through it.
There can be at least 7 oil gallery plugs fitted if required. One at either end of the horizontal oil galleries (4) and for the oil pressure relief valve bypass gallery (2). At the outer end of the head horizontal gallery (1) which feeds the rocker gear.
I would suggest that those oil gallery plugs which are proud of the block face should be machined down flush with the face unless the rear casing is recessed. The rear horizontal oil gallery plugs fitted to the inline 'A' Series engines have to be machined flush with the rear face of the block to enable the rear engine plate to fit.
Has the box to block attachment been upgraded to larger studs/bolts?

[les]

The plug in the first picture has been taken out and not screwed back in fully. The other is being stubborn ! I’m becoming more confident that the previous rebuild, apparently by a reputable person, has been done ok, not only because of the two threaded plugs but also the block has been countersunk for the studs, and the head looks in good order. I’d like to see if other plugs, if any, are fitted but wonder if it’s now necessary to remove the gearbox to see, as I originally planed. I'll be speaking to my friend on Saturday.
Removing the camshaft is next. The primary gear is straight cut as I think is the gearbox.
The bolts have been replaced with cap head Phil. I haven’t yet looked closely in that area to check if they are next size up.

[les]

Further work, the camshaft is by Kent cams, Megadyne 296. The gearbox to block cap headed screws look to be 5/16. Everything cleaned up now and ordered spares and gaskets etc, have arrived. I’m leaving the cam timing until last, as I’m a bit out of my depth with this variable cam sprocket, lining it up with the crank sprocket.

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[philthehill]

Les
A nice set of forged rockers I see.
Timing the cam is relatively easy though to do it accurately you do need at least two dial gauges - one to determine TDC and another to determine max cam lift at the specified degrees. A timing disc is a prerequisite as is the camshaft specification.

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Sorry about the Australian version but that is how it ends up.
Phil

[les]

Thanks Phil, I’d like to attempt it but don’t be surprised if I ask for your help if I do, it’s the starting point with the variable sprocket that worries me. I’ll see about the cam spec.

[philthehill]

Les
It may seem daunting but it is relatively straight forward
This is how I set my variable timing cam gear.
First:-
Fix timing disc to the front of the crankshaft.
Fit indicator pointer to read the degrees on the timing disc
Bring No: 1 piston to what you consider to be TDC.
Adjust timing disc to read TDC.
Fit No: 1 dial gauge and place indicator rod on the top of the piston.
Turn the crank clockwise so that the piston goes down an indicated 30m on the dial gauge.
Turn the crank anti-clockwise so that the piston comes up the 30mm to presumed TDC and then goes anticlockwise down 30mm.
Adjust the timing disc to read TDC at the mid degree point as indicated on the timing disc.
You may need to do this several times to determine the true TDC as in reality the piston remains at TDC through several degrees of crankshaft rotation and that is why you have to allow the piston to go down the bore the 30mm and up again and down 30mm in the reverse direction .
Adjust the timing disc to indicate true TDC against the pointer,
That means you have the true TDC to set the cam timing against.

Next:-

Fit the second dial gauge to the top of the block with the indicator on top of the rocker push rod.
Turn the camshaft to get maximum lift of the push rod as indicated in the cam spec.
Again use the 2nd dial gauge to determine max lift by turning the camshaft backwards and forwards.
The cam spec should tell you what the maximum lift is at ???? crankshaft degrees.
Turn the crankshaft so that the timing disk which is attached to the crankshaft is at the correct degrees for camshaft max lift.
Tighten the cam gear adjusting bolts and that's about it.
I would recommend that you run through the setting process at least a couple of times to ensure that all is correct
After setting the cam timing I do use a lump of plasticine on top of No: 1 piston after dummy fitting the head and rocker gear with a used head gasket - then turn over the engine, remove the head and check the clearances with the plasticine being a good indicator.
Good luck with the cam setting.

[les]

Thanks for taking the time to post that helpful information, it’s appreciated. I’ve found the specification for the 296 camshaft the lift is 8.22mm inlet.
I only have one magnetic gauge so presume once I’m happy with TDC and set the timing disc and pointer, I can move the dial to the inlet push rod. At the moment the crank and cam sprocket are loosely in position with chain and dots lined up. Any subsequent adjustment I’m hoping can be achieved on the variable cam sprocket. The only specification I have in degrees is the cam duration, which is 290 degrees (inlet).
I fitted the flywheel housing today and the flywheel but not tightened at this stage. So I’m heading towards this cam timing soon.