Crankcase Joint Oil Leak

[Owen Snell]

I have an oil leak along the crankcase joint, both in front of and behind the strainer. It's definitely the joint leaking - I have the van in the air and got it completely clean after adding some UV dye to the engine oil.

It's more of an annoyance than anything else, but it does wind me up.

There are traces of sealer used when mating the case halves, clearly unsuccessful.

I'm not taking the engine to pieces now, so looking for something that will maybe improve the situation. I've ordered a can of Permatex 82099 sealer that allegedly works from the outside. I'm a little sceptical, but it's worth a go.

Is there any reason not to slack off the lower case nuts before applying the sealer (oil drained and all cleaned) and then tightening up after, or is that a no-no on an installed engine?

[wreck]

I had a leak like that , very annoying , I tried ultra grey RTV , and even 24 hour JB weld with no real luck . I recently pulled the engine down for an inspection and to fix the leak . The case flange area needed a little work .( just dressing with a large flat sharpening stone . )