Oil Welch Plug

[david.g.chapman]

I have my engine on a stand, and looking at the back of the block, there is a small 5/16 inch Welch plug on the right hand side at the end of an oil gallery.
I need to be sure this isn't leaking. The top edge of the crankshaft oil seal carrier is dry, do no oil had been trickling onto it. If I change the plug I could introduce a leak that wasn't there before.
Could I test the plug in some way by pressurising the oilways in the engine from the oil pressure sender hole (I have a small air compressor)?
Even though the oil has been drained there must be a residual amount that would be forced out?

Dave Chapman.

[rgh0]

That plug blanks off a drilling that runs through the blocks original cam pushrod bores, I think to drain oil from them. The drilling is not pressurised and not connected to the oil feed system so not likely to leak and as its an oil passage not likely to have corrossion. With no pushrods and followers on the orginal cam this area drains straight to the sump anyway on a Twincam. If the welch plug is not leaking or showing signs of damage i would leave it alone.

cheers
Rohan

[david.g.chapman]

Thanks Rohan.

The crankshaft oil seal surface has some grooving and minor pitting under my inspection glass, so I've ordered a Speedisleeve CR99311 to fix it.

Dave Chapman.