Oil leak, front of engine

[The Veg]

You may recall the video I posted a few weeks ago in the 'What did you do to your Lotus today' thread of my Plus 2's engine running for the first time in four years. I ran it again today to test the new fan wiring setup and try to get the ignition timing adjusted. After getting the engine good and warm and holding an idle I went to check the timing and pointed the strobe at the crank pulley and saw some airborne droplets. I shut the engine off immediately and investigated. I found an accumulation of oil on top of the 'lip' of the lower tank of the radiator, and there was a coating of it on top of the frame member which dripped down off the rear edge of the member. The oil doesn't seem to have come from the dipstick tube as there wasn't much oil on the stick or the tube, and from what I could see of the rear face of the crank pulley from underneath, I'm not convinced that it's coming from the front main seal, thank goodness.

So where could it be coming from?

[h20hamelan]

Will it only leak while its running.
How is the breather, could you use another oil cap with a provision for another breather?
Sure its not coolant getting mixed with some oil. So your oil or coolant level is going down. And if the dipstick is removed while running.

[The Veg]

Definitely while running as it didn't leak during the past four years of sitting, and the puddle forming on the floor was definitely oil.

[webbslinger]

I'm not acquainted with +2's, but "airborne droplets"? , does your car have an oil cooler?

[JonB]

Sounds like it’s coming from the timing chest seal.

Welcome to the club!

[el-saturn]

airborne droplets - reminds of US when we're drinking: we also tend to whitewash our TC issues, don't we? sandy

[prezoom]

I would first try removing the oil filler cap while the engine is running to see if there is a significant amount of blow by pressure present. Quickest thing to check. If there is, I would put the cap back on and check the tube from the cylinder head to the air box back plate to see if the screen is not some what plugged. Since you are finding oil slung about, I would then pull the front crank pulley and take a good look at the area where the seal contacts the pulley for wear. If there is a groove present, a seal saver, along with a new seal may be the easiest answer. Unfortunately, there is insufficient room in the front cover to relocate the position of the seal so the seal contacts the pulley at an un-worn area. I have had good luck in being able to slightly moving the seal, new of course, from its present location to an un-worn spot and solving an oil leak. Mostly with differential pinion flanges.

[richardcox_lotus]

See if any oil has settled on the little “tab shelf” in the block/head above the generator near no 1 exhaust. That to me is a good indicator of a timing chest top seal leak.

Also double check your oil pump - if oil is leaking around the upper side of the sump and being picked up by the fan belt.

Good hunting.

Regards
Richard

[Donels]

I had a similar problem on a cross flow engine I had rebuilt several years ago. The oil was coming from the front of the crank pulley, leaking between the crank and pulley. I think I fitted the oil flinger the wrong way round! Cured by use of silicon around the retaining bolt and washer.

[The Veg]

I would first try removing the oil filler cap while the engine is running to see if there is a significant amount of blow by pressure present. Quickest thing to check. If there is, I would put the cap back on and check the tube from the cylinder head to the air box back plate to see if the screen is not some what plugged.

Right now instead of the tube I've got a rubber elbow in the breather hole, connected to a 1/2" ID Tygon hose going into and unsealed catch-bottle (a small plastic jug actually). After running I saw condensation droplets inside the hose so I suspect the blow-by is OK but I'll do the cap-check too just to verify.

Since you are finding oil slung about, I would then pull the front crank pulley and take a good look at the area where the seal contacts the pulley for wear.

I've been thinking of putting on a new pulley anyway since the old one has some chips on the edge, so that sounds like a plan.

If there is a groove present, a seal saver, along with a new seal may be the easiest answer. Unfortunately, there is insufficient room in the front cover to relocate the position of the seal so the seal contacts the pulley at an un-worn area. I have had good luck in being able to slightly moving the seal, new of course, from its present location to an un-worn spot and solving an oil leak. Mostly with differential pinion flanges.

Interesting. I'm having trouble visualizing this but I'm sure it will all make sense once I get in there.

The engine was rebuilt several years and two owners ago, but very few miles put on since- probably under a thousand. I know that dis-use is bad for seals; does dis-use agree with a potential seal problem here?

[The Veg]

I had a similar problem on a cross flow engine I had rebuilt several years ago. The oil was coming from the front of the crank pulley, leaking between the crank and pulley. I think I fitted the oil flinger the wrong way round! Cured by use of silicon around the retaining bolt and washer.

I would never have thought of that type of leak!

Thanks guys, sounds like plenty of things to go on. I'm feeling better about it already. The upside is that it doesn't lose oil fast enough to endanger running.

[The Veg]

airborne droplets - reminds of US when we're drinking: we also tend to whitewash our TC issues, don't we? sandy

Now that I think of it, 'airborne droplets' sounds like something from a medical lecture on infection-control. And in a past employment years ago, I did among other things, oil-change services on the big vacuum pumps in hospitals...the pumps that provide the 'suction' used in ORs and ICUs or anyplace where a patient may have a drain or a respiratory issue. While I doubt that any pathogens could live very long in 30-weight compressor oil, I nevertheless treated the stuff as contaminated and wore gloves, handled with care, etc. I never got sick from it but then I worked everywhere in hospitals every day so my immune system was probably better than Superman's because of the constant low-level exposure. Some of the larger/older pumps were a pig-job that would have made Mike Rowe proud!

[StressCraxx]

I had a similar problem on a cross flow engine I had rebuilt several years ago. The oil was coming from the front of the crank pulley, leaking between the crank and pulley. I think I fitted the oil flinger the wrong way round! Cured by use of silicon around the retaining bolt and washer.

I would never have thought of that type of leak!

Thanks guys, sounds like plenty of things to go on. I'm feeling better about it already. The upside is that it doesn't lose oil fast enough to endanger running.

Well then, consider it's just marking its territory, like a fine British motorcycle of the same era.

[webbslinger]

When I asked if you had an oil cooler in my previous post, I was thinking about your new fan and your mention of oil on the lower part of the radiator and crossmember. With all the leaks I've had (every one described here so far) I've never seen oil come forward like you describe, or seen drops flying around. It got me thinking about an oil cooler leak. I'm curious, please let us know what it turns out to be.

[jk952]

If memory serves me correctly, x x - oops it didn’t