Airhead - weird oil leak

MickDB1

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Hello there
I have been trying to put me old airhead back on the road - It runs but it has developed a weird old leak coming out of the lower head retaining nuts. Meaning the exposed nut positioned at 6 o'clock. I have had Heads in bits twice with a problem on one of the heads - like I bodged a loose valve guide in March then got a polite bollockin from Duncan (Arkwright) = rightly so too - I miss Duncan a lot. Lately I got a professional mechanic to do the right thing on that guide - I have changed oil - only put 20/50 in - a new filter - proper O ring and spacer and right amount of oil too.
I did give it a good ridearound getting my boots wet with drips of oil. I thought at first it was the upper tubes that conduct oil back to the crankcase but then the other side started weeping out of the same 6 oclock nut. It has the proper thick washer under nut. It is definitely not the head gasket and also defintely not the lower "pushrod tubes"
Any thoughts or ideas Please
Pisstakers - I dont mind as long as it solves my problem :thumby: :thumby:
 
So, to be clear, you mean the nut which attaches to stud numbered 2 here Mick?

Edit: If that IS the case then the oil has to be coming from somewhere else? The top studs / 'oles feed oil to the rockers which then returns to the sump via the push rod tubes. Them's the only places oil can be coming from, Shirley?
 

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Pete - Its as if its ooosing out of top/outside of stud 2 or thereabouts. Mikey - I capped the head off base side with plate then pressure tested tubes with 15psi - I used a rubber car wheel valve to jam up to the more open, top end, of the tube - No showy of bubbles or owt - Tomorra I am removing the nut and washer and running for a while to check if its coming through the stud threads (if I can see owt better) fookedif Iknow. Have you removed the studs ever and are they blind holes/or drilled into another oil course or owt?. Thank you for helping up to now
 
Pete - Its as if its ooosing out of top/outside of stud 2 or thereabouts. Mikey - I capped the head off base side with plate then pressure tested tubes with 15psi - I used a rubber car wheel valve to jam up to the more open, top end, of the tube - No showy of bubbles or owt - Tomorra I am removing the nut and washer and running for a while to check if its coming through the stud threads (if I can see owt better) fookedif Iknow. Have you removed the studs ever and are they blind holes/or drilled into another oil course or owt?. Thank you for helping up to now

The diagram shows the oil circulation, Mick. Should make my meaning clearer?
 

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I know it sounds crackers - Just to clarify even more - As the "head" fits over the barrel as in Petes picture above the head is secured and retained by the 4 Rocker nuts and 2 exterior nuts @ 12 and 6 o'clock I know there aint no "oilways" there. It does it both sides too !!!!!
I will photo tomorra if I can. Thank you again all.
 
Pop the heads off and check them and gasket and cylinder faces for flatness or damage

There is no oilway anywhere near there only the pushrod tubes as pointed out
 
The oil can only be coming from the two sources mentioned. If it’s ending up in the stud then it has to be coming from the cylinder head gasket and then to the stud by gravity / engine pressure? Bizarre that it’s happening on BOTH sides though! If that’s the case, it suggests that summat has been installed incorrectly on both sides? So as Jay says, whip the heads of and check.

Good luck!


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Perhaps post a photo Mick, might be something obvious when people see the potential direction of flow etc.
 
I know it sounds crackers - Just to clarify even more - As the "head" fits over the barrel as in Petes picture above the head is secured and retained by the 4 Rocker nuts and 2 exterior nuts @ 12 and 6 o'clock I know there aint no "oilways" there. It does it both sides too !!!!!
I will photo tomorra if I can. Thank you again all.

........I'll have some of that Mick :D
 

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It is definitely not the head gasket and also defintely not the lower "pushrod tubes"

It seems too early to rule anything out. Think about gravity. And if the heads are being taken off and put on again as often as it sounds, are you using a new head gasket each time? No-one yet has talked about the rocker cover gasket leaking. But that would be not in the region of the lower head bolt.

If truly that stud is leaking oil on both sides, you have a massive crack in your barrel and the oil is coming from your bores through to the stud. As things go, this is improbable bordering on the implausible, especially both sides.

So, how often have you used those head gaskets? Just saying'.
 
Not done owt yet Pete. Had to help me mate with a leak in his bathroom. Should be in shed tomorra. My plan is to expose the stud(take nut and washer off) run bike on fetish tickler and see what shows. If that fails to pin it down its off with the head and swap it with another r100ead I have. If that dont sort owt its gonna be a noisy foulmouthed shed !!!!!!
 
Not done owt yet Pete. Had to help me mate with a leak in his bathroom. Should be in shed tomorra. My plan is to expose the stud(take nut and washer off) run bike on fetish tickler and see what shows. If that fails to pin it down its off with the head and swap it with another r100ead I have. If that dont sort owt its gonna be a noisy foulmouthed shed !!!!!!

Fetish tickler! Looking forward to the video Mick! :thumb2


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Fetish tickler! Looking forward to the video Mick! :thumb2


I think its his accent Pete

Probably slowed down it should be "Fast Tickover"

BUT hey I could be wrong :aidan Who is bringing the popcorn?

P>S> Mick!! Did you put the head gaskets on the right way around?? :hide:
 
Well - I thought it unusual that nobody had heard of this oil leak !!!!!!
Not surprising after todays investigation !!!!!!!!!!!!!!
Removed 6 and 12 O'clock nuts and washers and ran engine on a fetish tickler for about 5 mins usual oil started weeping down inside of one fin of the heads.
One side is slight - turther is a drip every 10/15 seconds.
I thought it ridiculous and highly unlikely that both of the upper tubes could go porous at same time
Maybe its that - the stud holes on LHS pot dont weep at least.
Looks like Mikeyboy was right first time he told me (who would have put money on that :D)
removed the LHS head and swapped for another head I had spare
HERES A TIP - to remove the rocker block seats I used a 10mm sleeve anchor inserted and just nipped up then taped out the block with a pin
put me new old head on and that dont leak
HERES ANOTHER TIP - yes I did put one of the head gaskets the wrong way around first time in March but not the second or thrid time since
(I read keep print to outside on internet = load of bollocks) They have a just slightly off centre on the bottom holes = one side has a wider surface than other side on the flange = Clue is yer pushrod get a scratching with the gasket material
Maybe doing tuther tomorra then I am going to set summat of a test jig up to test the whole head and rocker cover assembled to prove that they are leaking through top tubes.
Phoned "The Man Who Knows His Stuff" and said I was wrong and he was right = and he laughed- tittered very sympathetically = He's a good lad
More - as I drop more bollocks
At least I am getting less leaks on me bike = Me mates bathroom job has no leaks you will be glad to hear too !!!!
Thanks for all your help
 
Well - I thought it unusual that nobody had heard of this oil leak !!!!!!
Not surprising after todays investigation !!!!!!!!!!!!!!
Removed 6 and 12 O'clock nuts and washers and ran engine on a fetish tickler for about 5 mins usual oil started weeping down inside of one fin of the heads.
One side is slight - turther is a drip every 10/15 seconds.
I thought it ridiculous and highly unlikely that both of the upper tubes could go porous at same time
Maybe its that - the stud holes on LHS pot dont weep at least.
Looks like Mikeyboy was right first time he told me (who would have put money on that :D)
removed the LHS head and swapped for another head I had spare
HERES A TIP - to remove the rocker block seats I used a 10mm sleeve anchor inserted and just nipped up then taped out the block with a pin
put me new old head on and that dont leak
HERES ANOTHER TIP - yes I did put one of the head gaskets the wrong way around first time in March but not the second or thrid time since
(I read keep print to outside on internet = load of bollocks) They have a just slightly off centre on the bottom holes = one side has a wider surface than other side on the flange = Clue is yer pushrod get a scratching with the gasket material
Maybe doing tuther tomorra then I am going to set summat of a test jig up to test the whole head and rocker cover assembled to prove that they are leaking through top tubes.
Phoned "The Man Who Knows His Stuff" and said I was wrong and he was right = and he laughed- tittered very sympathetically = He's a good lad
More as I drop more bollocks
At least I am getting less leaks on me bike = Me mates bathroom job has no leaks you will be glad to hear too !!!!
Thanks for all your help

Hmmm ... tubes?
So ... Mikeyboy was right?

I still think it’s the cyl head pushrod tubes mick.
I thought you were going to pressure test them?
it was the push rod tubes then Mick?
 


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