JohnD Posted August 5, 2017 Share Posted August 5, 2017 I posted this over on the TSSC site, but when I tried to link someone to it, they couldn't read it, because they aren't a member. So much for the 'community of Triumph'!Anyway, I reprint it here:Correcting the sump flange, to prevent leaksTriumph engines (car or bike!) are notorious for oil leaks. In the small chassis series, four or six cylinder, the sump gasket is a guilty in many cases, and the DPO (Damned Previous Owner) is often at fault. Overtightening the sump bolts bells the metal around the holes in the sump flange, to that the falnge inbetween doesn't seal. Further tightenign just makes it worse, and the problem recurs even if you rebuild the engine, as the belling persists. To correct this, it's necessary to do some minor fettling to the sump flange. Here's how, with pictures. 1/ Clean up your removed sump, especially the gasket residues on the flange. Do the same to the block. Apart from bits of old gasket preventing a seal, you can't work on a filthy sump. 2/ With a strong light behind, place a straight edge along the flange. The bells around the bolt holes will show up as light gleams through the slit. Mark the holes with a felt tip. See Pic.1. 3/ You need a 'post' in a vice. I use a length of steel plate, 1/2 x 2 x 6", but some hard wood could do as well, but ask a local metal working company if you may look in their skip for an offcut. It could be thicker, as long as it will fit inside the flange, and as wide as the the distance between holes, and the top must be flat. See Pics. 2 and 3.4/ Hold the sump so that the hole you wish to correct is in the middle of the post, and the flange is flat on the post. I've drilled a smal hole there to help me locate it. Pic 4. 5/ Now, with a hammer, beat the bell around the hole flat. Use a small hammer, and do not apply great force - the blow should come from the elbow, not the shoulder. Half a dozen firm, not hard blows will often do, and you will hear the sound change from a ringing to a duller sound as the bell is flattened. See pic 5. 6/ Check the flange with the straigt edge again. Repeat the hammering until the gap that the light gleams through is straight. Your flange may not be absolutely flat, indeed slightly curved, but correcting that is a much bigger job, and this amount of curvature won't cause leaks. See Pic 6. 7/ When you fit the sump, do NOT overtighten the bolts. The 'Book' torque is 16-18 lbf/ft, which is a bit more than hand tight. What's 'Hand tight'? is hard as you can turn the bolt just using hand and wrist strength. What's "a bit more"? GIve the bolt a final tweak with the whole arm. Hope that helps prevent sump leaks!JohnPS For some reason I cannot upload all the pics in the post. They will appear below. Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 5, 2017 Author Share Posted August 5, 2017 Pic 2, which appears sideways, a common and irritating problem. Turn your head! Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 5, 2017 Author Share Posted August 5, 2017 Pic 3 Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 5, 2017 Author Share Posted August 5, 2017 Pic 4. Sideways again. Grrrrrrrrrrrrrrrrrrrr! Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 5, 2017 Author Share Posted August 5, 2017 Pic 5 Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 5, 2017 Author Share Posted August 5, 2017 Pic 6 Quote Link to comment Share on other sites More sharing options...
1968Vitesse25 Posted August 5, 2017 Share Posted August 5, 2017 Take a large ball bearing and put a divot in the mating face of the flange, dishing the flange up under each bolt head. As you tighten down the bolts, the divots will flatten out giving you a true clamping face.Fit sump gasket with a bead of Hylosil 300 RTV no more sump leaks. Quote Link to comment Share on other sites More sharing options...
Richard B Posted August 6, 2017 Share Posted August 6, 2017 Nice and methodical John. Just to add over-tightening the sump bolts can also create a nice S curve in the aluminium bridge piece.Either repair it by skimming or replacing. I think the after market steel bridge pieces are a better bet for a leak free life. Quote Link to comment Share on other sites More sharing options...
yorkshire_spam Posted August 6, 2017 Share Posted August 6, 2017 Thanks for posting John, I suspect I need to do this to my sump soon! Quote Link to comment Share on other sites More sharing options...
RedRooster Posted August 6, 2017 Share Posted August 6, 2017 Would a spreader plate between all the bolts help prevent the bolt holes distorting? Quote Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 7, 2017 Share Posted August 7, 2017 Some sumps do have a stiffener plate to minimise distortion, but after all these years its not a major problem, a ball pein hammer and mallet to reverse the distortion will work well for the next 40 yearspower take off coverplates on our exchange truck gearboxes used this technique since the 1960s to revieve used platesits common when sheet steel and thick paper gaskets are mated together Quote Link to comment Share on other sites More sharing options...
Hogie Posted August 7, 2017 Share Posted August 7, 2017 Hi John, using a wood or nylon hammer may give a slightly better finish.Steel hammers to flatten sheet can easily spread it. Wooden hammers/mallets help compress the material.Roger Quote Link to comment Share on other sites More sharing options...
ferny Posted August 7, 2017 Share Posted August 7, 2017 There's a reason a lot of manufacturers use sealant now... http://www.henkel-adhesives.co.uk/2838_UKE_HTML.htm?nodeid=8797716348929 Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 8, 2017 Author Share Posted August 8, 2017 Vitesse 25.The objective of this work IS a "true clamping face". Distorting the face to allow you to distort it again with the bolts? Too much tightening force.Richard,An S-Curve in the Bridge piece? I'd have to see a picture of that, to see what you mean and how sump bolts could achieve it.RR,A spreader plate between the bolt holes? The flange is already indented in the pressing to stiffen the flange between the bolts, and there are spreaders between some holes, at the back. I don't see how more will help.Roger,Fascinating! How does a wooden hammer/ mallet compress, yet not spread the material? How does a nylon hammer improve the 'finish', when all we want is a good seal? Please show us your mallet with a head small enough to do the above job? And please note my comments on controlling the force of the blows.Ferny,Yes? and what is that reason?JOhn Quote Link to comment Share on other sites More sharing options...
nicmk1est Posted August 8, 2017 Share Posted August 8, 2017 think it comes down to over-tightening! hand tight does the job not brute force.......i use pin hammer to flattened my sump holes Quote Link to comment Share on other sites More sharing options...
RedRooster Posted August 8, 2017 Share Posted August 8, 2017 Quoted from JohnD RR,A spreader plate between the bolt holes? The flange is already indented in the pressing to stiffen the flange between the bolts, and there are spreaders between some holes, at the back. I don't see how more will help.JOhn the indents can't be working then or you wouldn't need to hammer the bolt holes flat again.RR Quote Link to comment Share on other sites More sharing options...
ferny Posted August 8, 2017 Share Posted August 8, 2017 Quoted from JohnD Ferny,Yes? and what is that reason?JOhn To seal it. Quote Link to comment Share on other sites More sharing options...
Hogie Posted August 9, 2017 Share Posted August 9, 2017 Roger,Fascinating! How does a wooden hammer/ mallet compress, yet not spread the material? How does a nylon hammer improve the 'finish', when all we want is a good seal? Please show us your mallet with a head small enough to do the above job? And please note my comments on controlling the force of the blows.JOhn[/quote]Hi John, I'm not a panel beater but have learnt a few things from a friend.Take the example that you wanted to put a 90' bend in a piece of sheet steel. The bend also has 6" radius (compound curve).The edge of the steel for the flat sheet is longer than the edge of the finished article.So you need to bend it on a dolly and somehow shrink the metal - otherwise it will pucker.If you used a steel hammer each blow would tend to try and squish the metal and this make it bigger (stretch)Using a wooden hammer/mallet that is softer than the steel the metal would bend but as it is trying to get more metal into a smaller place the metal would now start to compress'shrink.So you get a neat finish with the wooden hammer than the steel.Very bad explanation but I'm sure there are good tin bashers on here that will explain better.Rather than a smaller nylon hammer use a smaller nylon dolly.http://www.hotbikeweb.com/shrinking-metal-with-mallet-stumpRoger Quote Link to comment Share on other sites More sharing options...
Hogie Posted August 9, 2017 Share Posted August 9, 2017 Quoted from RedRooster the indents can't be working then or you wouldn't need to hammer the bolt holes flat again.RR The indents between the holes support the flange material. They do not support the bolt holes.The indents have to finish away from the holes and so the hole can get distorted.Without the indents there would be oil passing out everywhere.Roger Quote Link to comment Share on other sites More sharing options...
RedRooster Posted August 9, 2017 Share Posted August 9, 2017 I know that which is why i mentioned a stiffener plate earlier. Quote Link to comment Share on other sites More sharing options...
Gt6s Posted August 9, 2017 Share Posted August 9, 2017 Quoted from 1968Vitesse25 Fit sump gasket with a bead of Hylosil 300 RTV no more sump leaks. NO WAY once you have seen lines of silicone sealant hanging like snotters out of an oil pump strainer it puts you off the stuff. I use nothing more than a smear of grease on both sides of paper gaskets. Done that for years on cars, Trucks, Heavy plant, Fuel tanker delivery pumps, filter blocks and manifolds works on coolants air/fuel, and hydraulics. Bonus IN AN EMERGENCY you can reuse the gasket.Laurence Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 9, 2017 Author Share Posted August 9, 2017 Roger,That guy is clearly an expert, but I fear he misinterprets what he is doing.The disk he demonstrated needed to be made it into a bowl. That's what happens if you hammer the centre of the bowl, and leave the rim untouched.But the hammering must be right up to the rim, whose rim will crinkle if you stretch the adjacent metal too little.He removes the crinkle by hammering just inside the rim, to stretch it more.I do know whereof I speak - the 'bonnet bulges' on SofS and it's dad, Silverback were my work.John Quote Link to comment Share on other sites More sharing options...
Hogie Posted August 11, 2017 Share Posted August 11, 2017 Hi John, perhaps I posted the wrong/inappropriate video clip.Making bulges is easy (sort of) shrinking the flange (or better still NOT expanding it) is more difficult.Steel hammers are not the way forward for shrinking.Roger Quote Link to comment Share on other sites More sharing options...
JohnD Posted August 11, 2017 Author Share Posted August 11, 2017 Roger,Panel beating is indeed an art, and every artist has their own way.I'm happy to be a beginner!JOhn Quote Link to comment Share on other sites More sharing options...
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