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Progress-new thread Monday

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Breather installed, nice part.

Just came back from a two mile run, got two drops or so out of the scroll seal.

Now for a longer run to see just what is what.

If this pans out it indeed was not the scroll seal but is blow by on rings. That's a whole different kettle of fish than a leak per say.

More to follow.
 
Noop, no fix. Ran about 5 miles and still leaks badly.

Guess there is no hope for it, got to pull the engine again this week so I can see that rear seal. Well sort of a seal.

However, I do know a lot more about that seal than when I started this. One thing I can not claim is that it is blow buy. That new vent has almost a 3/8 or bigger hole straight into the crankcase. It vents and vents well.

Think I will try the old finger test on the vent hole before I go further and see just how much blow by I have if any at this point, of course there is always some.

More to follow.
 
Did the finger test just a small bit of pressure both in and out. Nothing excessive at all in my humble opinion.

Checked the plugs again both 3 and 4 indicate I need to do some more carb adjustments they are both fuzzy black and I had switched with 1 and 2 to see what was what. Think my back carb is very rich for some reason. OK not a problem, maybe the rings have sealed after all. Engine runs quite well, smooth and starts easly as fast as you can get you hand off the starter switch.

I have now exhausted all that I know to do other than pull the engine and look at that rear bearing cap makeing sure it is seated properly along with the eyebrow. Of course looking for what ever else I can see while in there at that scroll seal.

Could that scroll seal be cut backwards for some other engine or do all A40s turn the same way? Hmm, will check just because.

More to follow sometime this week, seems wife wants to start on Christmas decorations and such, must keep peace here this time of year especialy.

Oh yea, that darn clutch still has a bubble in it, LOL.
 
JPSmit said:
Keoke said:
JPSmit said:
Jack - is there a LBC or (old time) shop near by? We keep trying to solve this one online but this might be a time to consult with a mechanic?
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===== /bcforum/images/%%GRAEMLIN_URL%%/shocked.gif Wot!! You mean, ain't non of these folks mechanics?? Sure could ah fooled me!---Keoke-- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
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O man I really stepped in it there /bcforum/images/%%GRAEMLIN_URL%%/blush.gif - er um - of course we're all mechanics /bcforum/images/%%GRAEMLIN_URL%%/grin.gif (and all special in our own unique way /bcforum/images/%%GRAEMLIN_URL%%/wall.gif ) Just stop right there-----Keoke /bcforum/images/%%GRAEMLIN_URL%%/banana.gif
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---------------------------------------------------- /bcforum/images/%%GRAEMLIN_URL%%/lol.gif
 
No question in my mind as the dip stick shows lower and lower.
 
Jack, you have seen me post that I am blessed with some truely awesome friends that are much better wrenches than I. Maybe it is time for you to quit beating yourself up with part replacement and have somebody else take a look at it. Sometimes when somebody fresh to a problem looks at it, there is a simple and obvious solution that you are simply missing. We all wish you well, but we would really like to see you find your problem and enjoy Miss Agatha. Oh yeah, be careful with the Christmas decorations if they involve climbing.
 
Hehe, I will overcome. Gesh, I am the wrench. I even still make little race cars go like skat. This has become a personal challange.

I no longer climb for anything, Christmas lights outside are all on the front bushes and shrubs.
 
A man after my (decorative) heart!!!

You will get it Jack, if not this engine pull then maybe next!! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Well, think about this.

I now have no back pressure. Three releaf tubes, compression all the same cylinders. Was getting black oil, changed it, not sure anymore.

Still leaking.

There is a hole in there that has to be the size of a pencil lead. I know it could be a long narrow one.

The oil is comming from the rear crank area.

Something is wrong with the rear main scroll cover fitment, drain hole in bearing cap is pluged although I ran a wire through it while it was in the engine. Eye brow is not makeing proper connection with the rear bearing shell although I did seal with RTV.

Not too many possibilities left, I should be able to pull the rear bearing, check the fitment and drain hole and reinstall with tac sealer and reinstall the eyebrow the same way. Checking clearances for a .002 fit at the same time. If the eyebrow is not close enough to the rear bearing seal I can adjust that with a bit of fine tuneing on the ends of the eyebrow and enlarging the bolt holes a bit to allow for a closer tolarance.

Something strange in there. I will find it and it will be dumb. But let me tell you we all will have tighter engines after rebuilds when I am done.
 
Jack,

Why do you have to enlarge the mounting holes? Didn't the car run for awhile without leaks? Make sure there are no burrs on the block and scroll seal where they touch, draw file them. Make sure the mounting screws are not too long. Is sealer needed between the 3 faces of the main bearing cap and the block? How much play is in the rear bearing? Check the direction of the knurling direction on the crankshaft vs. engine rotation. Check the back plate for warp, twist, and and irregularities. Draw file both the backing plate and the block. Double check the plug in the oil passage. Check around the cam shaft hole. Check the valve cover seal and the head gasket seal areas. Check the oil drain back holes in the rear main cap.

Take lots of pictures of everything.

We had a similar problem with the front end of my son's 1500. It turned out to be a bent and dented front plate leaking around the cam shaft and the oil galley plug. The plug was so tight we had to weld the allen wrench into the plug to remove it, but even being this tight it still leaked. It took 3 or 4 tries to stop the leaks. It is really hard when you start with multiple leaks. Keep at it and check all the details.

Can anybody think of any other areas for leaks or any other procedures Jack should be doing?

Phil
 
I sure agree with your check list Phil. I will do all of those things and a couple more even. Would only have to enlarge the eyebrow mounting holes if it was not tight enough but I think it is, was just thinking out loud, would only be a draw of a rat tail file in any case.

It did run without major leaks but since this rebuild it has been awful. Something changed.

Supose I could have a burr some where, it surely is something. However it does not leak between the backing plate and the block it is behind the backing plate and the only thing there is the scroll seal.

Can't wait to get it open myself.
 
You do of course realize We are all seating hear on the edge of our seats waiting for the next installment on this adventure series?
Who care's if Hollywoods on strike and there's nothing but reruns on the tube.
We have Jack With an adventure that revials any thing on the tube. Now this is reallity LBC!
/bcforum/images/%%GRAEMLIN_URL%%/eek.gif
Come on Jack ....Jerk that Engine out were dying Out here to know!
 
I'll tell you what changed between the first and the second rebuild, I have oil pressure now. Hmmmm, wonder what that means.

Cold here now, will be 34 degrees tonite but do have my stuff done so I can spend some time in the garage as long as it is warm enough.
 
Jack,

Thought the engine was already out. If not,drain the oil out before you pull the engine, as to not contaminate the leaking areas, and post pictures, so us experts (LOL) can be beside you this time.

Requested pictures:
Fan
Crankshaft knurling
Back of flywheel
Engine plate
Area of leak
Rear main cap showing drain back holes
Block mating surfaces of rear main cap
Cap mating surfaces of block
Scroll seal
etc...
 
Oh yes, will do.

Wonder if a bit of talcum powder would make pics show up better.
 
I think the talcum powder is a great idea. Might want to take pictures first and than try the powder. Just in case it doesn't work.
 
Yep, good idea, will do. Fluids draining now.
 
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