Another Smokey T160

Gday Fellas. I've recently rebuilt a T160, only to find that once warmed up it blows a bit of smoke. My initial thoughts were that it was a problem with the rings. After a lot of trawling through the net, I looked towards it wet sumping. After a short ride and the engine up to temperature, the dip stick was low and I took the sump cover off and found 500ml of oil came out.

Unless someone thinks otherwise, I was going to replace the oil relief valve, oil check ball valve and possibley the oil pump. However I don't want to do any of them for no reason.

What is the best way of diagnosing exactly what is cause the wet-sumping, so I don't replace expensive parts or do work for no reason? Note that it doesn't seem to be losing much oil while stationary for a few days.

Cheers

 

The head was rebuilt with new valves and valve guides, so I'm assuming that's all good.
Compression is 135 psi for the two left cylinders and 150 for the right, so they seem ok.
I would like to go through the oiling circuit to see if there is a fault there.
What order should I check the various components. And is there more to wet sumping than just a faulty oil pump or oil relief valve? You mentioned a cracked engine casting, for example, can this lead to wet sumping?

 

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I'll double check that one.

 

Excuse my ignorance. I'm still finding my way around the bike, i've had a look, but if the pipes were the wrong way around, there wouldn't be oil flow would there?

 

Science has proven that man flu is real, so I'm feelin your pain bro!
But yeh, this must be the only t160 that doesn't wet sump when stationary, I put a pan under the motor with the sump plate off, and after 3 days maybe a teaspoon of oil. But after a run, about 500ml. Also it doesn't start to smoke until fully warmed up.

 

The original air cleaner has been removed and is running pod filters. The breather has been connected to a small gauze filter.
It's a May 1975 build no 4548. The oil is high zinc 20W50.

 

Thanks Rocker. Yeah I did see that one, that's what led me to chase the probability that the cause was wet sumping, Originally I thought it was a ring or valve clearance issue (it might still be) but before I strip the bike down I want to make sure I have the oil pump, relief valve etc. sorted.
I'm just waiting for the parts supplier to get back from overseas, so I can get the right pump for that model. Apparently they are very expensive, so I might do the relief valve first and check the impeller clearances on the pump. If the pump looks obviously worn, then I guess I'll have to replace the pump.
The thread that you posted says that he paid $130.00 for the updated pump, but he has a bonneville, so I doubt that would fit a T160??

 

I know its been a while since I asked about excessive smoke, but I finally got around to working on the bike,
Just to update, I ended up stripping down the motor and found it to have glazed bores, to the point that they were a mirror finish!! So Ive rehoned, reringed and am in the process of reassembly. I have a few more questions but will put them in another post.
Cheers