Following on from the other thread about a rad leak, I went out to the garage this morning to find a rather large water leak coming from the Scott. The whole rad was empty, and it appears that the water is coming from the sparking plug recess for the right hand plug.
The recess is half-full of water (as the tilt of the block means it overflows before filling entirely) but clearly it’s a major leak. Anyone else had this?
That sounds a strange one! Are you sure it is not a leaking rad or hose which is simply filling up the spark plug ressess?
That was my first thought Stan, and it’s happened to be before, but no, it definitely appears to be “welling up” in the recess.
Before breaking out the spanners I will inspect it all minutely though; I’d hate to whip the head off just for a leaking rad pipe!
Looking at across sectional drawing of the head it is difficult to see how water could find a passage out of the head to emerge via the plug recesses. However, if that be the case, all is not lost!
“K” Seal is probably the best thing to try first – but if and when you need a permanent fix, you could do no better than go to Alan Noakes who will fit new “skulls” in your existing head – and his charges very reasonable.
Yes, judging by the recommendations in the other “leaking rad” thread I ordered some KSeal yesterday.. just in case.
I do actually have a NOS head for this engine; better than the existing one as that has 18mm plug ‘oles with adaptors whereas the new one will take 14mm plugs directly, but the screwed-in water pipe threads look a bit iffy so I shall have to spring for a 1″ X 20 TPI (I believe) tap to clean them up before going to Scottparts for two new pipes.
I’m hoping the bike will last until late Autumn (end of the riding season for me) before I have to do this job, and I need to adjust the clutch too which is another pain-in-the-bum job!
Here’s the offending hole-
OFF with the head!
Fill the hole with some chemical metal.
Second thoughts , enlarge the hole from the top and again fill with chemical metal,
because you will not be able to access it from the rear
Would it be possible to tap the hole and fit a threaded plug?
Could be more permanent than some of the resin fillers —
I’ve cleaned out the hole with a cleaning agent, removed the 18-14mm adaptor and filled the leaking hole with so-called Liquid Metal.
I found a suitable engineering-standard washer to fit under the adaptor and also covering the leaking hole to give the repair some mechanical strength, so tomorrow (my weekly run out) I will refill the rad with KSeal and top it up with water.
As long as it lasts a couple of months then good enough.
Update…it didn’t last and is leaking again. I’m loathe to use the rad sealer so will just suffer it until the end of the riding season when she’ll be put in dry dock for a range of little nuisances to be sorted.
Main thing now is to buy some water tubing from Scottparts and clean up the threads in the head.