General TR Still Losing Oil

[KVH]

Now that I have my car running great, I'm focused on the loss of oil. It's not from a leak. What shows up on the floor seems trivial. Teaspoons. But I'm losing 1/2 quart a week, driving maybe 120 miles. I'm still running a bit rich, and, to me and at least some onlookers, the exhaust is black, not blue or gray. My plugs have been sooty when too rich, but now they're clean and gray/brown.

I rebuilt my engine 9 months or so ago.

Can it be that I screwed up the rings? Wouldn't my plugs be wet or oily if my rings were allowing oil past the block?

Any more ideas about my oil loss?

 

[Gliderman8]

I had a similar situation with my TR6. It drove me crazy trying to find out the source of the leak. It turned out to be coming from the dipstick tube! The crankcase was not properly vented. Once Ken (pool boy) helped me sort things out the leak stopped. May not be your case but I'm putting it out there as a possibility.

 

[TomMull]

I think Elliot's on the right track. I think a plugged system or one injecting too much oil into the intake could account for all your issues. Tom

 

[Geo Hahn]

Sometimes when there is an oil loss but not much of a puddle on the garage floor it is because the oil is only lost while the engine is running well above idle - suggesting a leak that is from a source under pressure.

Do you have a spin-on adaptor? I ask that as they can be a troublesome seal (the one between the adaptor & filter head) that can cause a running leak.

In any case, I'd be examining the engine, not the floor, to pinpoint the leak (if there is one).

 

[Gliderman8]

I would also check the valve cover gasket. I switched to a silicon gasket and that was a big improvement.

 

[Rut]

I know these are different engines, but I had a similar issue with an MGB engine that I rebuilt and it turns out that the modification I did to the tappet cover caused the problem. The MGB uses 2 tappet covers with 1 vented to the carbs via a rubber hose that splits just before connecting to the SUs. I made an aluminum plate to replace the forever leaky tappet covers and in my infinite wisdom vented both the front and rear individually to each carb without the 'steel wool' to slow the oil vapors so they could condensate and run back into the crankcase. My modification allows for really good negative crankcase pressure, but it consumes oil faster than normal while keeping the rear seal leak free. I haven't decided how or if I'm going to fix the issue, but any increased flow from the crankcase to the carbs or manifold via a PVC valve can potentially increase oil consumption. I don't know if this will apply to the TR engine, but it's so similar to my issue I thought I would bring it up.
Rut