my 2056 Type IV leaks a couple of 3-4" oil spots every time I drive it, which is a couple days a week lately. the drain plug has a new copper washer, and the taco plate has new rubber and paper gaskets with gasket sealant.
I think the leak is from the case halves. Mobil1 10W-30. Would a higher weight oil make a difference?

Man, I hate oil leaks!

Yes, did it for many years when I auto-Xed my 914-4.

Just takes time good work, proper O-rings and good sealants. Jake Raby did a thread back in the day about what he used, at that time. I just followed his lead, and it worked out great.

Still did not keep people from coming over an looking under my car for leaking oil when it was found on the course.

I would let them look, then point to the car that was leaking the oil, as you could see a trail of oil from the corse, through the paddock, to his trailer where we was working on it. Really bunch of Stenotypists

I do not have the post in my archives sorry.

If it is a case leak, then you will have to split the case.

can a 60's era british motorcycle be made leak free? the answer is, I am afraid, no. too many mating surfaces, paper gaskets, heat cycling, they will all leak eventually. it can be mitigated with sealing compounds, proper lubricants and careful assembly, but its going to leak. 10-30 synthetic is too thin, 20-50 dino will slow the drip and dissipate heat better. originally designed to run straight 30wt or 50 wt depending on climate.

I’ve owned my stock 76 2.0 with 120,000 miles for over 20 years. I use Brad Penn 20/50. The car has never leaked a drop of oil.

There's an old joke about why the Brits don't build computers?

Answer: they can't figure out how to make them leak oil.

I rode a 62 bsa 650 pre unit construction for many years. Never leaked oil.

Oh yeah, 914 doesn't leak oil either

I heard 914s stop leaking oil when they run out of oil! Seriously a few drops is not that bad. Using 914Rubber’s extra thick valve cover gaskets really helps.

We have three drivable 914’s and only one leaks and it needs a case reseal.

not to be argumentative but I have never dropped an engine from a 914 that was not covered in oily crud, especially under the cylinder cooling tins. the base gaskets scrub from use and they leak, two different metals and expansion rates, oil gets by. pushrod tube seals and oil cooler seals are notorious for leaking over time. curt, I think your recollection of your 63 bsa is clouded. they leak from the rocker shafts, the poorly designed plain bush on drive side of crank and the shitty felt gasket on the trans mainshaft. my 51 goldstar is as oil tight as can be and it pisses oil when ridden more than around the block. they all leak at the cylinder block/ case surface. least I have ever seen is my bmw r75, but it still weeps when ridden at the cylinders.

Fully-synthetic oils will create leaks, which is one reason why they tend not to be recommended for use in air-cooled VW engines, other than race motors, with their vertically-split crankcases. Modern semi-synthetics are better, or a good quality traditional mineral oil. I ran fully-synthetic in my drag race motors, but always semi-synthetic in the road cars.

Try swapping to a semi-synthetic – or a modern mineral oil from Valvoline, or similar.

will do!

I hesitate to say this, but the only oil leak my 73 had when I bought it from Dad in 2002 was from the oil cooler. When new gaskets were installed, the leak was gone, and to this day Mistress doesn't leave a trace of her passing anywhere! The motor has never been out during the current 58K miles, and I hope to keep her that way during the rest of my lifetime!

with Keith,the OP should change to a high zinc quality mineral 20/50 and be done with.

OT: I thought at first you were talking about leaking water into the cabin and both trunks...Also next to impossible. Back to regular programming.

Very possible. I have been leek free since dropping the motor for the body work 2 years ago- it was the third time I did the o-rings for pushrod tubes, and did the front crank seal oil cooler seals and there torqued the heads/cylinders that were getting some blow by, torque was half of what they should be- now, leak free all the way around. Oh and I rum Bradd Penn 20:50 oil, motor has 153k miles, of which I’ve put about 20k on it since I owned it, about 3k since the restore