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lower crankcase leakage

Posted: Mon Nov 01, 2010 2:59 am
by Mutineer
Hullo
Took my century for a good 2 hour run yesterday(in 2 hour long runs with some sailng in between)
It ran and started pretty good, though I noticed some fuel leakage at the bottom ofthe crankcase /top of the drice shaft
I'm going to give the bolts a tighten, but how dire is it?
thanks

PS Thanks to Billyboy for the inspiration I polished up one of my brass tanks to an unholy sheen!
and did some polishing on the flywheel..whilst running, letting the gull do the work

Re: lower crankcase leakage

Posted: Mon Nov 01, 2010 11:58 am
by Collector Inspector
Intersting!

B

Re: lower crankcase leakage

Posted: Mon Nov 01, 2010 5:18 pm
by Mutineer
Hey Bruce
Never encountered that before?
It did have a slight leak(very slight not pouring out or even bubbling) in the seam where the tiller arm attaches, as is common
I'm pretty sure though that the lower leak is seperate,,or at least it looked it
I can have another look when I go back to where my motors live

Re: lower crankcase leakage

Posted: Thu Nov 04, 2010 2:47 am
by Todd
M -
I'll take a stab at this. All my 'Gulls ooze around that seam. What I think is going on is oil gets pushed past the lower crank bushing - no seals, remember - and onto the top of the drive shaft where it tends to get slung into that drive tube joint. I suppose you could try making a gasket or sealing it with some sort of goo. But you'll be defeating one of Seagulls most celebrated engineering features. "If it's covered with oil, it won't corrode."

Re: lower crankcase leakage

Posted: Thu Nov 04, 2010 5:05 am
by Mutineer
Thanks Todd
I hadn't noticed it on my other gulls so I was wondering if it was sign of some ailment
It's good to know I'm not alone, nor does it seem to be a problem..hurrah
Happily, as a result, I too will not corrode..or at least my hands.

Re: lower crankcase leakage

Posted: Thu Nov 04, 2010 11:47 am
by Collector Inspector
Hmmmmm, my too SDs have/had a gasket.

None of my other gulls "ooze" from that spot.

I would not think too much of a problem unless the lower bush is flogged out.

Might vibrate if really bad.

We all enjoy "our Weeps" from time to Gull Time eh?

B

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 7:03 am
by Mutineer
Well
I might be calling it a year for sailing...I made it into November!
So maybe I'll pull the bottom end off and look at the top 'o the drive shaft ( top 'o the driveshaft to ye! )
Hey Bruce (and or any of you knowledgable folks) You're referring to the lower crankcase bushing yes (I'll look at my shop manual too) Shoulds I just look for excessive play and wear? Like yourself none of my other gulls leak from this area so I think having a look would be good..I do have another entire crankcase for this century
It was a rebuild from two by a motor enthusiast..not sure if he was an "expert" though ...I certainly am not.

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 7:19 am
by billyboy
do you notice that there is always a wet oily residue inside the magneto baseplate where the coil and points are? if so this is another indication that the bushings are starting to wear. might be time to dig out that spare.

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 1:50 pm
by Collector Inspector
I would not get too carried away with "Oily Residue" in the ignition plate insides Mate. My comment was for the lower bushing leak and weeping externally only.

Top bushing is basically free from, let's say, normal wear and tear with any reasonable lubrication from petrol/oil mixes as the flywheel, well ballanced ex factory, tends to keep everything pretty well aligned when Gull doing it's thing.

Any oil in that region is basically "HO- Hum" and would be after many years of operation if not from various lube efforts for the point runner as applied by past many user/owners.

Just a point to consider in that nearly every Gull has a history and that the lower bush can be a problem only if the poor dear has had a hard life.

Regards

B

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 2:51 pm
by Charles uk
Bruce I've had way more top bush problems than bottom bush, with Seagulls.

125's & 170's give the top main bearing bush a fairly hard life, as do all the Wartime & earlier seagulls with the "coolie hat flywheels".

Could this be a Northern Hemisphere thing?

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 3:12 pm
by Collector Inspector
What are "125's & 170's" bushes?

Never had anything to do with them.

Comment on only what I know about, Old Dears eh?

B

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 3:33 pm
by Collector Inspector
Actually, I am at the moment, stuck on a road just south of Nannup western Australia. Coast trip stalled because my old Ford decided to have a Hissy Fit!

Waterpump belt and after unloading the boot, only one I do not have a spare .................Crap!

RACWA on their way.

Pic out ofdrivers' window........Phone works and hard work sending this.............Hope it makes sence....

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 3:37 pm
by Charles uk
Are those giant termite nests?

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 4:04 pm
by billyboy
[quote="Collector Inspector"]I would not get too carried away with "Oily Residue" in the ignition plate insides Mate.

there is a fair bit of difference between the normal lubrication and build up in there and the wet stuff to which i am referring. so humour me mutineer and check it anyway eh? :D

Re: lower crankcase leakage

Posted: Sat Nov 06, 2010 4:08 pm
by Horsley-Anarak
I thought it was a black cat in a coal cellar.

(all looks black to me)

H-A