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850 ES oil leak when on side stand

Submitted by mike_steer on Mon, 19/10/2020
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Commando

This is a post I wrote earlier today (Monday).  I have rectified the problem now but thought I would post it anyway as it might come in handy for anyone else who might be looking for solutions to a problem or at the very least something else to consider. 

Just been for a 15 mile run on the 850 ES Commando.  100 miles on the clock since total rebuild. Got back home put bike on side stand with engine running and me sat astride it just checking things were ok around the engine area, when I checked the left side of the bike it was in the process of dumping a load of hot oil onto the drive. Shut the engine down for a closer look.  I shone a torch around the head gasket area but I wasn't 100% convinced it was coming from that area, I didn't see anything definite or a positive oil trail other than the oil appearing through several fins.  It's as if the oil had collected somewhere during the journey!!  

Things to consider

I haven't re-torqued the head as yet from the rebuild

To cure previous oil seepages around the fourth fin I fitted a Yamaha 650 reed valve to release pressure in the crank 

Studs at the front of the head have been fitted using a suitable sealant 

I have looked through various posts on here covering similar subjects which I take on board but it was the amount of oil I was concerned with not a leak overtime or seepage but a largeish deposit in one go, probably about 150/200cc's until I switched the engine off

Problem Solved

Having just gone back out into the garage to have another look in more depth I see the rocker feed pipe (06-5561) that runs between the carbs at the back of the cylinder head has melted against the back of the head and was pushing pressurised oil out from the melted fracture, with the engine running, from back to front between the fins around the gasket are.  Hence the amount of oil and and me being unable to pinpoint the exact location area, till now.  I did have one of the carbs off last week and obviously didn't ensure that the feed pipe was in the correct position when I refitted the carb.  'Every day's a school day'.

Submitted by john_holmes on Tue, 20/10/2020

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That pipe is a high pressure feed, if it breaks then your big ends lose oil pressure. Best to replace the original nylon/plastic version with one in pipe covered with braided stainless reinforcement which has a further layer of clear plastic. Without the final layer of plastic the stainless braid will hacksaw through anything it touches. I was lucky with mine I had just started the bike and looked down to see a spray of oil coming from a free end of the pipe that had fractured at the banjo.

Submitted by alan_sessions on Tue, 20/10/2020

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A few years ago, I returned from a ride to find an amount of oil on right side of engine - the plastic oil feed to the head had melted near the top banjo - the bike has always seemed to run hot & I think the pipe was original - please inspect yours for brittleness & replace with braided hose for peace of mind

Submitted by john_neely on Wed, 21/10/2020

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I rebuilt mine some time ago and wondered what the rubber grommet on the vertical line was for.

I found out that it fits onto a small wire clip attached to the r/h carb and holds it safely away from the cylinder head.

I can picture it in place if required.

Submitted by steve_constable on Wed, 21/10/2020

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John

can you post a pic of this clip?

I can’t find it on the parts list. I had always thought the grommet itself was to stop contact and rubbing wear.

cheers

Steve

Submitted by john_holmes on Thu, 22/10/2020

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I run my pipe outside of the carbs on the right side, you can keep it away from the carbs and engine by holding the banjo in position as you tighten the nut, as mine is stainless braided and uncovered so I have wrapped it in self amalgamating rubber tape where it could touch and its ran that way now for 20 years.

Submitted by john_neely on Thu, 22/10/2020

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I got the clip from Les Emery, I ran the feed pipe as instructed on the outside of the first engine plate, using the rubber covering to stop it rubbing and everything lines  up perfect.

Hope this helps more pictures if you want them

Attachments
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Submitted by mike_sullivan on Tue, 27/10/2020

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Another option for covering the braided cable is shrink tube, you'll need a shrinkage ratio of 3:1 iirc in order to clear the connections - did this on mine. 

 


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