Gasket alternative grooving tool
For some years now I have stopped using gaskets on my engines after deciding that they were never there for my benefit but used to compensate for poor manufacturing, and in my experience always leak after a while.
I am talking of course about old British iron and not modern machines, my Triumph twin has only a cyl head and base gasket as they are dissimilar metals.
I know I am not the first to do this, but this is my method and can honestly say that non of my old bikes leak oil after running for a few years even with HTF fluid in chaincases etc.
It also removes the need to re-tighten after first running.
Faces have to be flat and a bit of lapping may be necessary, after that a groove is cut in one half and this gives a means of retaining the jointing compound (I use Hylomar Blue as its good enough for Rolls Royce).
The obvious tool to use is a Dremel type device, mine is made from an old hand piece from a flexi drive connected to a 12 volt drill motor but the important bit is controlling the the cutter as its a freehand process.
A simple guide attachment was made and a cutter from a 1/8 centre drill ground to a D bit shape does the job, about 15 thou deep is enough.
It is important to work from the inside face so any slip ups do no harm and just like milling,direction of cut has a bearing.
The first pic was freehand and I just about got away with it, the second was guided with the attachment and the difference is pretty obvious.
I hope this helps in keeping the oil where it should be.
Great Idea OlderDan! Wish I would have thought of it. I noticed you stayed a bit south of center line too which is smart in my book. Turnips are notorious leakers!! Back when I built mine I did lap all the faces but used an amazing product I found back then called Kawasaki Bond...best sealant I ever used...had a silver look/compound in it and it came apart well and cleaned up easily. Blue and Red silicone was just out then and never did have much luck with it until the formulas improved. The early KB I used is Long gone now and haven't tried the newer silicone based version...but like you say if Hylomar Blue is good enough for Rolls...it'll work for me. Haven't heard of that before but will have a look for it over here.
Had a water issue with one of the vehicles while back with a cover plate and 2 hold downs. Think its a casting port on the block, not sure and why not a freeze plug although its a machined face & bore...maybe an Option port?? Dealer said to only use Black RTV. The plate is SS with a slight return flange and the block is AL and of course it's in a PITA place to reach and clean without removing the entire front clip, but got it best I could, applied the thin coat as directed, cross torqued between the 2 nut/studs, checked...all good. About a month later the temp gauge spiked again. Checked, sure enough dripage! This time I pulled the 2 studs by hook or crook and fabbed a flat sanding tool I could get up there with...sure enough not flat and also checked the new flange plate but it was flat. This time I goobed about twice as much Black RTV to squeeze out to the edges of the plate and smoothed it to form a fillet seal to the flange. So far it's fine now about a year later.
Next Time if it happens I'm using your idea and maybe some of that Rolls stuff!
Thanks for the great share. ~PJ
‘‘Always do right. This will gratify some people and astonish the rest.’’
Your method is the business and if I had the means I would copy, I guess you use o-ring of the roll and join them
(melt or cyano)?.
I do convert to o-rings when I can but that's limited to circular items.
Your work is something to aspire to.
I have fixed many a problem child leaker with this stuff. I do however love the idea of a tool to create grooves for sealant to lock into. O-rings even more, but I would have to do it on a manual Bridgeport, so it wouldn't' look nearly as nice as the ones Tony did.
Click for full size.
Chasing around manually.
On the left is the manually traced version with the CNC version on the right.
Both worked equally well. Never let lack of CNC be an excuse, the world was built on manual Bridgeports.
This what I do at the other end of the pushrod tunnel. In stock form the distance between the two surfaces is slightly variable and the factory used a soft rubber style gasket 2/3 mm thick. This would tend to slide about with use and most old engines have punch marks on the surfaces to try and hold the gasket. As the head to cylinder distance can vary I prefer a system which is designed to allow axial movement. I bore out both head and cylinder to take an O ringed joining tube. Goodbye to leaks.
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