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oil from the tunnel and more

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jvandyke

jvandyke

Luke Skywalker
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I thought I had a pinion seal leaking at the differential but upon closer inspection, it seems oil is coming out the driveshaft tunnel. If I jack up the front (as I have recently a few times) oil will drip steadily out the back end of the tube. It doesn't stink like I'd expect the pumpkin's gear oil to. Is this what happens when it comes through the scroll seal thingy? Gearbox seems to be as full as I left it.
Really getting a bit aggravating to chase oil leaks around. Now considering an oil trap on the tappet cover vent tube as well. I recently added a vent line from the mechanical fuel pump blanking plate which seemed to help but it's still coming out. Maybe I should consider a total rebuild.

I've got a line off the rocker cover to the SU air cleaner (and evidence of oil on the filter where it comes in).
I've got the standard 1098 tappet cover draft tube open to atmosphere.
I've got that new line from the fuel pump blanking plate rising up to one of those filters.
I drilled a tiny hole in the pretty chrome oil cap as it should be vented I believe.
Still I have oil oil oil on the ground. Doesn't stop me from having fun but it's annoying.
fuelbreather.JPG
 
jvandyke, You and me are in the same boat on this one. From the day I purchased my midget I noticed the thing wanted to mark its territory everywhere we went. When you have a few buddies that have freshly paved driveways it becomes a bit more of an issue when they want you to park in the street. With mine I started with the top and worked my way down. I changed the valve cover gasket then made sure I wasnt leaking around the oil fill cap. Looked at the oil filter and made sure that was sealed nice. The distributor gasket was worn and showed signs of leaking around the base. And the dip stick was blowing oil for a while from the new Weber carb. After addressing all that I still have some leaking that like you said doesnt stop me from doing what I need to on the road but it gets annoying. I think my oil issue is coming from the same area as what your talking about.
 
If you have a 1500 it's different, leaky no doubt but different. Maybe mine needs a rebuild, too much blowby and oily pressure everywhere? Don't know. Compression numbers are okay. I'll have to start systematically narrowing down exactly where it's coming from. That flow out the drive shaft tunnel is bizarre though. Don't detect much oil loss from engine or gearbox but it's obviously coming from somewhere. Oh well. The 1098 were certainly unique with that draft tube. Maybe I can stuff stainless steel wool in the lines to catch some of the oil. I'm about ready to do a catch can and just manually empty it back into the valve cover every few days.
 
Out the back of the tunnel. The rear tranny seal. Yep, it can be done without removeing the tranny but it is really a tough job.
 
jlaird said:
Out the back of the tunnel. The rear tranny seal. Yep, it can be done without removeing the tranny but it is really a tough job.
Click to expand...

Me agree with Jack.
 
Oh my golly Hap, you made my day. Thanks.
 
While I suspect it is the seal, check obvious things. My tranny was leaking persistently, looked up under and one of the bolts attaching the gearbox had fallen out. Quick fix.

Finally, I did replace the seal - was leaking a tiny bit - added some transmissions stop leak and tada - it even shifts better (shh don't tell anyone I resorted to the chemical solution)
 
It's either the rear transmission seal or you're getting a lot of oil coming out the scroll seal. When you have it parked after running look at the bottom of the bellhousing to see if it's dripping oil There's a hole with a cotter pin at the bottom that oil will come out if the scroll seal is letting a good bit pass. If not, then it's more than likely the rear tranny seal.
 
And cardboard to put in the garage under the car is still the cheapest fix there is. A solution from the "we tight" club.
 
I've got the cardboard and there's nothing coming from the bellhousing, which surprises me a bit as the other thread on my oil leaks has be wondering about bad rings and excessive pressure in the crank case which I would think would show up first at the scroll seal but that's the one place where it isn't leaking. I'll plan on some compression tests and maybe a leak down test but I'm pretty sure the tunnel of oil is a different issue with the rear tranny seal.
 
No no, leaks will not show up at scroll seal if it is correctly installed and I would guess that yours is fine then. However that said if the breathers are not open it will push from there.

You, as you stated are pushing oil out the breathers. The engine is developing pressure in the crank case because of the bad rings????? and the heavy fumes are takeing the path of least resistance.
 
I'm starting to face the fact that an engine tear down is on the horizon, although it is down to a pretty small leak up front at the moment, just the rear one is now quite bad. Maybe I can nurse it along for a while yet. I wonder what an engine over haul would cost if I did almost everything myself.....hmmmm
 
Done properly with no major problems 1K should handle a nice refresh.

However, what do you mean by the rear one only is bad? The rear tranny seal, cheep stuff.
 
jlaird said:
Done properly with no major problems 1K should handle a nice refresh.

However, what do you mean by the rear one only is bad? The rear tranny seal, cheep stuff.
Click to expand...

Rear tranny seal appears to be source of oil from drive shaft tunnel, they say. Refresh will have to wait. Will have to get creative to nurse it along for a bit.
 
Ok, get a new tranny seal.
 
Well I thought it prudent to check the gearbox oil level. After over 200 miles and oil from the tunnel every time I park for a while (especially if the front is high) the level is right where I left it.
So, where the heck is that oil coming from? Could my draft tube be dumping that much oil during cruising that it collects in the tunnel and it has finally made the journey out the back? I loose quite a bit of engine oil so I guess it must?
Another reason to rig up a catch can I guess.
okay, I'm off to the garage to start scheming.
 
I think I got it.
After another round of clean, run and check.
I found, during clean a drip off the extremely bottom edge of bell housing, and the low part of the curve where the crank goes through the front cover. Close inspection and it was wet on the front of the bell housing. Oil pan?
I check bolt tightness...several were pretty loose. Tightened and normally after a decent run, the car would show the two spots after it sat for 15 minutes or more. Not after the last two runs though! Maybe just maybe I have a leak free Midget, that's rare, no?
 
Maybe just maybe I have a leak free Midget, that's rare, no?

As I far as I know, Unicorns, Sascwatch and Leprechans are easier to find....
 
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