Help with oil leak

Try some silicone sealant on the bolt shank.

Morning, I’ve not dealt with an oil leak there before but my thoughts are it’s two possibilities:

1) The washer and bolt has retained oil. It’s VERY hard to actually clean oil out of an oil soaked bolt so it can appear to ‘leak’ when it’s actually just old oil hiding in the bolt/split washer. 

2) My understanding is that the only reason that bolt could leak is if the crank case seal has broken down. If this is the case you have a much bigger issue. The crank cases should be split, inspected and re sealed if the cases haven’t fretted/chaffed. 

Simply sealing the bolt might fix the leak but not establish the cause 

I just went through this here is my path over 2 years on a fresh overhaul

first the crank seals due to high crank pressure so check that

I did have a bolt leak on the upper rear, silicone did the trick i though .Im not sure those lower bolts have oil pressure.  

most oil stopped but i still had some between the right cylinders and fins. im thinking oring on head bolts? before i pulled the cylinder I had to check better. Cleaned the engine with brake cleaner and applied spray on foot powder. Took it around the pattern once and inspected and found the area of leakage right away . top over number 1. 2 small cracks not even visible with the eye. It was the older crankcase which is prone to cracking.  Oh the hook for a new engine block now and an end to my season. we learned a lot

good luck

Oozing bolts like your picture are fairly common from what it have seen over the years and usually aren’t a big deal. Most never see or find them unless they do what you did. I use Desenex foot spray powder to find things like this. I wouldn’t lose any sleep over it, but if you want to fix it remove the bolt and apply some Loctite 243 blue to the threads. Coat them fairly well and put a dab on the washer face and on each side. It should take care of it.