GB is not OK!

[Greybeard]

Been in the shed most of today. I have the short engine back in the frame. I've fitted the dynamo belt kit. I have the clutch and primary on. I've taken advice from 'Er Indoors' and stopped before I start making mistakes.

I'm glad someone here pointed out the issue of modern oil pump gaskets having holes that are smaller than the pump ports. The holes in this gasket were only 3/16"! I opened these up with a hot skewer.

Tomorrow I expect to get the engine running.

I'm now hoping that I can get to the BSAOC Norfolk camp at the weekend. It's a long run, so will give the engine a good start to its bedding in.

[muskrat]

G'day GB.
My next rebuild will be a lot quicker if I post it over to you!
Cheers

[Greybeard]

G'day GB.
My next rebuild will be a lot quicker if I post it over to you!
Cheers

Please do; you may not get it back though!

Waiting for parts to arrive has been the only real delay.

[Greybeard]

Pistons and block fitted. Mag timed. The head is on. I've stopped for lunch. I'm bracing myself for 'The Pushrod Experience' 

PS. Edboy very kindly sent me a pair of conrods from his stock. However, as I doubted my ability to achieve a good result with my 52 year old adjustable reamer, and, as I'd found a friendly, fairly local engineering shop, that obviously knew about old engines, (there was a set of Austin Seven conrods on the counter in for re-metalling) that I'd stick with my original rods. I took in a new standard bush that they fitted to the good rod. They bored out the little end of my buggered rod and machined up a new bush. They then machined both bushes to fit my pins. The work was turned around in one day and cost £103, but I'm happy.

[Topdad]

Excellent GB, obviously not only a distinguised gent ,but a pretty damn quick one to!! Bloody well done , by the way your Crank was really looking clean and ready for business , best of luck with the start up, Bob

[chaterlea25]

Hi GB
I hope you have not forgotten to fit the nut inside the crankcase mouth thats missing in the photo above?

 

John

[RoyC]

What is that boss with a hole in the middle ?

[Greybeard]

What is that boss with a hole in the middle ?

It's part of the mechanical breather mechanism. The cork disk behind it seals the pressure until the hole in the part you mention rotates and opens to release crankcase pressure.

[muskrat]

G'day Roy.
To add, it's driven by the peg on the cam pinion. The cork that GB mentions fits on the pinion first and the breather runs against the inside timing cover. The cork comes in various thicknesses so there is just a little crush to make it all seal. Crankcase fumes go in red arrow, travel up yellow arrow, take a left at green arrow, travel across cases and exit in front of g/box sprocket.
Cheers

[RoyC]

Thanks for the explanation, was wondering what it was when fitting my belt.

[Greybeard]

We have a problem Houston! 

I've got the head on and started to adjust tappets. When any of the valves are set, (8 & 10 thou) the engine will not go over TDC. BUGGER! It seems valves are touching pistons!

So, now I'm wondering about this later, 356 camshaft that I've put in. This engine has low comp slightly dished-top pistons in an iron head. Are you sure that combination is ok?

I wondered if I could somehow have mucked up the cam timing so I've had a check that the pistons are at TDC while a pair of valves are 'rocking', and yes, they are.

I've used a copper gasket, which I guess is slightly thinner than the composite original type. Could that be the issue?

Oh well, I'll take the head off and have a look-see.

Just had a thought: I've also fitted new cam followers. They might be incorrectly sized and lifting valves too high.

[bsa-bill]

I assume the engine turned over before you put the head on? (had a problem with my last rebuild, turned out to be timing side bush not machined square, shop sorted it for free).
Quick check ease the barrells up just enough to put some 16th/8th shims (washers?) equal both sides back and front and gently try to turn it over, might just save a bigger teardown

[Greybeard]

I've double checked valve timing is correct. Still no-go. Head is now off. I cannot see any evidence of valves touching pistons, but then I was only rotating the engine by turning the back wheel so no hard impacts were made. I did wonder if maybe the 356 camshafts used different cam followers but the parts book says no.

I have another copper head gasket, so I could try fitting two to increase clearance. I also have a new composite head gasket that, at least before tightening down, is thicker. I think I have another cylinder base gasket so doubling them up might help.

Advice, please!

[Greybeard]

I assume the engine turned over before you put the head on? (had a problem with my last rebuild, turned out to be timing side bush not machined square, shop sorted it for free).
Quick check ease the barrells up just enough to put some 16th/8th shims (washers?) equal both sides back and front and gently try to turn it over, might just save a bigger teardown

The engine turned over as it should when I just slackened off the tappet adjusters. It does seem as though the valves are kissing the pistons.

[Greybeard]

Hi GB
I hope you have not forgotten to fit the nut inside the crankcase mouth thats missing in the photo above?

 

John

When I reviewed the photos I thought, "Did I put that nut on". I did!