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Help with diagnosing oil leak

bic_bicknell

bic_bicknell

2016-06-17 09:58:00 UTC

Well. Last week I had to fix a damaged plug on the left hand side of the engine which was an easy fix as it was a leaking inspection plug. This week the Gods of fate decided to give me another oil leak for my 150 miles back from Bristol in torrential rain. This time it is on the right hand side and resulted in oil all over my right boot and blowing back all over the engine and pooling enough in the belly-pan to blow back over the rear tyre. Nightmare journey but managed to stay on and get home with frequent stops to gauge the situation and clean the tyre.

Anyway, today I removed belly-pan and gave the whole bike a degrease and jet wash. went for a test ride and got the oil leak within a few miles but I just can't see where it's coming from. Here's a few pictures that I took showing the front right of the engine. Enough comes out for it to cover the lower front engine block and drip down onto the exhaust header which then burns the oil off. On faster motorway speeds this eventually starts blowing back all over the top of the clutch casing and filling the belly pan. It's not the cylinder heads or base gaskets, pretty sure of that. Top suspect is the black metal oil line running up and then attaching into a thicker rubber hose that disappears behind the lower engine mounting bracket and then goes up to the oil tank. Oil is all over this line and forms a drip at the bottom but I just can't see where it could be leaking.

Has anyone had experience of this before of have a clue as to what I should do to locate the source of problem?


No. 47

No. 47

2016-06-17 11:00:00 UTC

Looks like pipework but check front cylinder cam chain tensioner cover and seal.

shadowman

shadowman

2016-06-17 11:41:00 UTC

Wen trying to trace an oil leak I have started with the highest trace and looked round at that level and then slowly worked down from there looking at all the places oil flows and could escape.

If not found then clean it up again, wrap in kitchen roll avoiding the downpipes and run at idle. You can usually see where the stain starts from and thats your issue.

You probably thought of all that already!

Good luck

bic_bicknell

bic_bicknell

2016-06-17 13:24:00 UTC

47 Mate, do you know what's involved just replacing that oil pipe? It seems to run from the top of the oil tank down to the metal one then round the front, behind the battery box and then all the way down to the bottom of the left hand side of the engine. Maybe I will just have to get a new one and fit it and see if the problem is cured.

No. 47

No. 47

2016-06-17 13:50:00 UTC

It's a real bugger to thread through and fix properly at each end and at mid support bracket fixing without removing radiator, oil tank and headers...........................................

Aphex

Aphex

2016-06-17 14:18:00 UTC

I agree about the rubber hose + pipe fitting,

Mine was leaking a bit from where the hose connects to the top of the tank, the clamp had deformed the hose.

It's the longer of the two here:


Image

bic_bicknell

bic_bicknell

2016-06-17 15:59:00 UTC

Well I have cleaned it all off and it's up on the stand but I can't seem to get it to show a leak with just the engine idling and getting hot. If I had to guess I think the only place that it could be coming from is the connection between that long metal oil pipe and the rubber oil hose that goes up to the tank. There seems to be a considerable overlap where it pushes on and there is a metal clip at the top. The metal clip is a crappy analogy of a Jubilee clip but you can't make it tighter as this seems to have been done in the factory with some sort of bend deforming the clip. The pipe below the clip is definitely not too tight because you can twist it with fingers so it's probably lubricated with oil which is another reason for me to think this is the place oil is coming from.

So looking at the complexity of replacing the whole oil line I thought I'd have a go at putting on another proper clip just below the OE one and see if that cures the problem. There's loads of room to do this and you won't be able to see it when the engine hanger has gone back on.

Can't test it now because it's just started to thunder and lightening and totally piss it down and I'm a bit tired of riding with a potentially oil spewing bike in the wet.

bic_bicknell

bic_bicknell

2016-06-18 08:44:00 UTC

Yay!

Went for a 20 mile blast up the motorway to test my Jubilee clip fix and it has worked. So that's where the leak was coming from - the join between the upper rubber oil line and the steel line. No need to remove the pipes, just an easy solution really, just took ages to diagnose. Not sure why it happened. Either just something that happens at 25K miles or maybe Fowlers overfilled the tank last week after doing the other oil leak and that somehow just increased the pressure sufficiently to blow the seal past the OE clip.

Sarasota_Steve

Sarasota_Steve

2016-06-18 11:50:00 UTC

Bic, glad you figured it out and it was an inexpensive and easy repair.
For non-UK English speakers here is a translation:

"A Jubilee Clip is a circular metal band or strip combined with a worm gear fixed to one end. It is designed to hold a soft, pliable hose onto a rigid circular pipe, or sometimes a solid spigot, of smaller diameter. Wikipedia"


Sarasota_Steve
08 990 SDR

bic_bicknell

bic_bicknell

2016-06-18 12:50:00 UTC

Ha ha Here's a picture of it on the job.... (you can just see on of the OE clip type at the top of the picture on one of the water pipes)

SDNerd

SDNerd

2016-06-18 20:17:00 UTC

Good on ya for finding that one, and sharing it with the rest of us.

And people wondered why I felt I had to replace all those shitty, too-thin gauge material, Oetiker/pinch clamps all over the bike ...

Aphex

Aphex

2016-06-19 04:04:00 UTC

Were any or you, I mean were any of your 990 SD's linked to the oil tank return tube inlets not being drilled large enough and causing an oil leak or the hose being blown off or leaking. There was a simple "go" gauge that consisted of a small ball end that must go through the inlet spout and into the oil tank. If it doesn't go through then the passage is not large enough and causes too much line pressure. My 990 SD was linked to the TI and was restricted so I drilled it with a grease coated drill bit.......I know crude but it work for me

It's the spout connection right at the filler cap where clamp #37 clamps in Aphex's illustration.


SD#1

Aphex

Aphex

2016-06-30 16:52:00 UTC

Post missing.

Merka685

Merka685

2016-07-01 02:33:00 UTC

Post missing.

Merka685

Merka685

2016-07-01 02:47:00 UTC

I just did a search and found the tech bulletin, it's TB 0904

Don't know if this link will work but it's here: www.peachtreecarwash.com/990_KTM_TSB_0904.pdf

if not do a search for KTM super duke oil tank tech bulletin that's how I found it.


And there's more to the bulletin, there's also new hoses

SD#1

KTM TECHNICAL BULLETIN TB 0904
SEPTEMBER 24 ยป 2008
Subject: Checking the Oil Tank Return Pipe Bore