TOPIC:

Raygun wrote: Bike pump?

No. Can't do it. When you understand the design of the leak down tester, Basically, a leakdown tester is 2 pressure gauges in series and in between the 2 pressure gauges is a .040" orifice. You supply 100 psi to the first gauge (which means a regulator is on the upstream side and the air goes through the orifice supplying the down stream gauge and the hose leading to the cylinder. if the leakage in the cylinder between the exhaust valves, intake valves and the piston rings is less than the flow through the .040" orifice, then the downstream pressure gauge will read 100 psi. If let's say the leakage was more then the pressure on the downstream side will read less. So if the downstream pressure gauge read 80 psi then the leakdown would be 100 - 80 = 20. 20 /100 is 20%.
Any engine with 5% leakdown is great. 10 to 15% leakdown marginal. Anything more than 15% should be repaired.
If the escaping air is heard at the exhaust pipe, then it's an exhaust valve problem. If the air escaping is heard at the carb, it's an intake problem. If the escaping air is heard at the oil filler cap, then it's piston rings. And a lot don't check, but if there's bubbles showing up in the rad, then a head gasket is at fault.
It's my go to test.

McBoney wrote: Right, all is well. Camshafts are in and this time I counted from the right timing mark. Everything is running smoothly when I turn the engine.

One minor issue is that some of the valve clearances have changed (four exhaust 1, 2, 5 and 6 have gone smaller by 0.1 and inlet on No 1 cylinder has to be increased by 0.1)... I hope this is not because the valves have been damaged. I have ordered new shims but I guess I will have to do a leak test to be sure. But although I have a compression test set, I have no access to compressed air....

Paul

I wouldn't get too excited about this phenomenon. You checked the valve clearance when the engine is at 3 degrees C ?? Co-efficient of linear expansion will throw off the clearances especially with an aluminum head. The manual specifically says

"VALVE CLEARANCE
Valve and valve seat wear decreases valve clearance,
upsetting valve timing. If valve clearance is not adjusted,
the wear will eventually cause the valves to remain
partly open, which lowers performance, burns the valves
and valve seats, and may cause serious engine damage.
Valve clearance for each valve should be checked and
adjusted in accordance with the Periodic Maintenance
Chart (Pg_ 10) and any time that clearance may have
been affected by disassembly.
Be careful to adjust within the specified cleara!lce.
Adjusting to a larger value will disturb valve timing
and cause engine noise.
NOTE: Valve clearance must be checked when the
engine is cold (room or atmospheric temperature"

Anytime measurements are quoted for fits and tolerances it's assumed that those specs are taken at 70 Deg F and at standard barometric pressure ( known as Standard temp and pressure) unless otherwise stated. Any company that operates under ISO 9001 has a "Standards Room" for quality control purposes and that room is kept at STP and any tolerances that are recorded include STP as part of the tolerance recorded.

Right, understood, and logical if one thinks about it.

I guess this engine will have to spend an evening in the kitchen again!

Paul

Kawboy wrote:

Raygun wrote: Bike pump?

No. Can't do it.

Oh ok I get it. I figured you could pump it up and the see if it held pressure but I guess it’s more complicated than that.

Ha, my new cam chain tensioner has arrived.

Someone on the forum mentioned that I would have to cut the spring.... is that correct? And if so, why and by how much?

And as it came without instructions, I take it the small rod goes inside the spring? What about a gasket?

Paul

McBoney wrote: Ha, my new cam chain tensioner has arrived.

Somewhere on the forum mention as made that I would have to cut the spring.... is that correct? And if so, why and by how much?

And as it came without instructions, I take it the small rod goes inside the spring? What about a gasket?

Paul

Which tensioner did you get Paul? Ned to know so the boys can properly advise.
If you got the ZX11 tensioner you may want to read this topic
ZX11 tensioner mod post