TR2/3/3A Locating source of oil leak

[BobbyO]

Oil is showing up under the car so I'm attempting to locate it's source. There is oil on the cover plate covering the lower forward portion of the transmission where it bolts to the engine. Is it possible residual oil, draining down in the engine after it has been running could find its way onto this surface? If not, where could it be coming from?

 

[KVH]

Oil is showing up under the car so I'm attempting to locate it's source. There is oil on the cover plate covering the lower forward portion of the transmission where it bolts to the engine. Is it possible residual oil, draining down in the engine after it has been running could find its way onto this surface? If not, where could it be coming from?

Yes, and I've go the same thing, as do many others here. I just rebuilt my engine, in part to replace the rear main seal to see if I could stop the leak. Looked great for a month, but now I've got oil there nearly every time. It's so difficult to isolate the problem. Could be oil coming from the front sealing block and running along the pan to the back. I had that problem, too. But you'd see oil on the pan bolt heads. Oil from the valve cover is really tricky. It can run down the rear of the engine and find its way to that same transmission area. So can oil from elsewhere. But a couple of teaspoons at the rear each day isn't that odd or unusual, and I'm certainly not yanking my engine again to hunt down that problem. I just accept (and exaggerate) what everyone around here tells me--that if it's not leaking oil it's not a Triumph.

 

[TFB]

I thought I had the common rear seal leak also,but it turned out most of it was coming from the fuel pump gasket.
Tom

 

[TR3driver]

Some other possible sources are the front seal on the gearbox, and the plug in the corner of the head. I think mine is mostly oil mist from the road draft tube (it's already past time for new rings).

 

[BobbyO]

Randall Initially thought it was the gearbox front seal since there was oil along the gearbox, dropping off the drain plug. And the gearbox was low. So, filled the gearbox, made sure the drain plug was not leaking and plugged the breather hole at the front of the gearbox, figuring that would be where the oil was coming from if it were the front seal. The car is not being driven but still got oil on the front of the gearbox so I figured it had to be residual oil draining through the rear seal from the last time it was driven. Just seemed like a long time for a drain down.

Am now wiping off the front of the gearbox daily hoping at some point there will no longer be oil, concluding drain down is complete. If that occurs, will start the engine to circulate oil and see if the leak re-starts. Hopefully, thereby proving its the rear seal. Or not (hopefully, that is) since that is not a good thing.

There isn't any oil at the top of the engine so don't think it would be the head plug or valve cover. Also, without the car being driven don't think it would be the draft tube or the fuel pump gasket. The hunt goes on.

 

[Merlin63Tr4]

To add to the sources of oil leaks, the main oil leak in my Tr was caused by a loose generator bracket.....

M.

 

[sp53]

My first guess is rear main and then residual oil from breather tube or then maybe the banjo bolt on the sender line. You can clean the area up good with some kitchen spray degreaser or solvent then fog some baby power on the area and the oil leak might/should show or they have the chemical you add to the oil and shows up under a black light.

steve