Breather/ crankcase pressure question?

[twoshirtz]

Hi guys and gals. I hope I'm posting this in the right spot.
I have a 74 tx 650a
I recently changed my head after discovering a very poor repair job but that's another story haha. So the new one came all bead blasted and fresh with guides and I swapped all valves ect. over and everything went smoothly. Put engine all back together and put about 200kms on it. I then changed my breather case from the double y style to the single port breather which I have just read might be a bit small and cause early leaks. A couple of weeks ago I started getting oil in my left and right intakes, I changed valve stem seals.. Still leaking oil!
Closer inspection I noticed it looks like the leak is coming from where the guide meets the head. I was wondering if it's possible that changing the breather to a single port has increased the pressure causing this or it's just the valve guides that need replacing? Any thoughts or help would be appreciated. Thanks

 

[Signal]

To check if the breather is the cause swap it back to the two port one and test. I don't think that's your problem though.
I think from the location of the oil around the guide head interface that the guide is not sealing in the head. Perhaps the O rings that go under the guide were not installed.
Others with more knowledge than mine will no doubt comment.
Cunning way to get photo!

 

[twoshirtz]

To check if the breather is the cause swap it back to the two port one and test. I don't think that's your problem though.
I think from the location of the oil around the guide head interface that the guide is not sealing in the head. Perhaps the O rings that go under the guide were not installed.
Others with more knowledge than mine will no doubt comment.
Cunning way to get photo!

Yes the inspection mirror comes in handy for a lot of things. My first guess was loose guides as I'm unsure how long this head had been sitting around until it was cleaned up and sent to me. The only thing that made me think maybe the breather is too small and creating to much pressure is that the left and right intake guides have started leaking simultaneously.

 

[Signal]

I think a lack of breather volume would most likely cause the cam shaft seals to weep before it forced oil through a healthy head to valve guide joint.
For your own peace of mind swap the breathers over and test. You will then know for sure.

 

[grizld1]

+1, Signal! The clutch pushrod seal would also be prone to leaking. In the photo the guide appears to be milled, and that's not an OE feature. The guides may be the source of trouble. They need to be sized to allow for a tight interference fit in the head, and the installer may have fudged that.