SouthernBanana Posted March 6, 2006 Share Posted March 6, 2006 Hi. I am running about 70mm clearance under my sump, and there is already severe evidence of grounding. The pan has been repaired with ally 'fill' weld already, but is also slightly porous (minor oil weep). Oily has suggest a fix, but this would then mean that in order to TIG an ally plate to the base of the sump, the heat generated by this would disturb Oily's porosity solution. I am thinking more along the lines of a kevlar plate (thin) as per a rally car sump guard.... What have people done to protect the sump where they run with low ground clearance? Link to comment Share on other sites More sharing options...
Sheds Moderator Posted March 6, 2006 Share Posted March 6, 2006 A heavy plastic skid is the mod of choice. Link to comment Share on other sites More sharing options...
SouthernBanana Posted March 6, 2006 Author Share Posted March 6, 2006 Thanks for the reply. Is this nylon or kevlar? Have people just used a flat section and bonded this on with a glue type product? How thick is the skid plate typically used? Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted March 6, 2006 Share Posted March 6, 2006 What have people done to protect the sump where they run with low ground clearance? Increase the ground clearance. Either go for higher profile tyres, bigger wheels or lift the car if you have adjustable suspension - Be careful as small changes in front ride height without lifting the other end as well could make the car understeer alot more. The problem is what do you fit the guard to - if you fit it to the chassis, you risk damaging that, and by definition, it reduces your ground clearance even more. I use 15" wheels on the road and 13" on the track for this reason. Link to comment Share on other sites More sharing options...
SouthernBanana Posted March 6, 2006 Author Share Posted March 6, 2006 a thin section of carbon sheet (i.e. 2mm or so) would offer enough protection to save the sump I think. This could just be glued on? I don't really want to raise the ride height as the car handles well, and Gary May seemed to think it was OK. Just concerned about bottoming out under braking at the ring, etc.... Link to comment Share on other sites More sharing options...
Rob Walker Posted March 6, 2006 Share Posted March 6, 2006 Carbon is no good, Cut up an old stainless steel wing protector and bond it to the center section of the sump pan with silicon. Link to comment Share on other sites More sharing options...
steve_bow Posted March 6, 2006 Share Posted March 6, 2006 SBanana, If you find a shop to fit some kind of skid plate around OXon/Bucks/Berks/Midlands can you let me know. As in my other thread have grooves too. Steve Link to comment Share on other sites More sharing options...
Griff Posted March 7, 2006 Share Posted March 7, 2006 You want an abrasion resistent material - we use UHMW-PE (ultra-high molecular weight polyethylene) in large quantities as a facing on steel fender panels for ships to rub against. It's much better than nylon etc, is very hard wearing, impact resistant, low friction, not too heavy (SG=0.95) and easy to cut, drill etc. It comes in flat sheets of various thicknesses - we tend to use 30mm upwards but 5~10mm is no problem either. Thickness is the key to getting a strong mechanical (bolted) connection. Drawback is you can't readily bond or glue polyethylene to anything and I don't see where you could easily fix a strong bracket to support a plastic sump guard. If anyone has a good idea for a bracket design, I could bring in some "samples" to try out. Just wondering though, if you have problems at 70mm clearance (I have 60mm and have problems getting out of my driveway!) then isn't adding anything at all under the sump going to make contact with lumps & bumps even more likely? It's not pink, it's medium red violet...! Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted March 7, 2006 Leadership Team Share Posted March 7, 2006 Have a look in your local supermarket for a cheap plastic chopping board - then butcher it (no pun intended 😬) to a suitable size. Job done Stu. Link to comment Share on other sites More sharing options...
SouthernBanana Posted March 7, 2006 Author Share Posted March 7, 2006 Griff. Hi. thanks for the info. I think that even if contact is more likely with additional protection fitted, hopefully, this will be countered by the knowledge that no real damage is being done (other than to the consumable skid plate). The only downside that you've pointed out is the potential inability to bond the polythene derivative (as opposed to mechanically fixing it).... Link to comment Share on other sites More sharing options...
Griff Posted March 7, 2006 Share Posted March 7, 2006 Stu has a good idea. The material for plastic chopping boards is also PE but a lower grade so not quite the same impact/abrasion resistance but probably adequate and easy for all to get their hands on quickly! It's not pink, it's medium red violet...! Link to comment Share on other sites More sharing options...
SouthernBanana Posted March 7, 2006 Author Share Posted March 7, 2006 good thinking batman! Only problem now is how to attach the bl00dy thing! Link to comment Share on other sites More sharing options...
anthony1956 Posted October 1, 2011 Share Posted October 1, 2011 what happened next?! it#s like the final episode is missing. Link to comment Share on other sites More sharing options...
Sheds Moderator Posted October 2, 2011 Share Posted October 2, 2011 When I get back to the UK (Nov) I could do some light engineering if I had a suitable guinea pig. Any takers? Link to comment Share on other sites More sharing options...
6speedmanual Posted October 2, 2011 Share Posted October 2, 2011 I am not a big fan of the sumpguard idea (for quite a lot of reasons which i will not go in to here. I run a K with DS. 65mm clearance under sump. On roads with a hig domed camber the sump can grind on the road. It has not ever hit on a flat road surface even after jumping on humps in the road. The only issue I have with this is that Aluminium being soft, grinds away relatively quickly. I have made a steel skid shoe for the leading edge of the sump. It is only 3.5mm thick, minimising any effect on the available clearance. This is working superbly, the wear rate of the steel being vastly lower than the ali casting. It also makes a load scrang noise when it does touch the road so provides an early warning of contact occurring. [The ali sump make about as much noise as filing pasticene, so I was not even aware of how often it touched the tarmac] When it wears through I will remove it and make a new one, or more likely refabricate this one with new material where it has worn. I have driven all over the Alps, Scotland and Wales with this very low ride height and not had a problem. [ include Col de Tende with it rock/gravel surface and water deflector stoney sleeping policemen] (not recommended for 7s - Renault Kangoo 4X4 better) As an aside regarding the issues Ant has had with the "blue plate", I find it hard to understand how this got damaged as it sits about 10mm higher than the lowermost points on the engine. Mine remains virtually unmarked despite traveling difficult roads. The last thing I would do is replace it with a thicker and more complex gizmo with more exposed fixings. Southernbanaba and Ant, if you BM me, I'll e-mail you back some photos of the Alpine Pass proven sump skid-shoe. Peter Edited by - 6speedmanual on 2 Oct 2011 22:40:28 Link to comment Share on other sites More sharing options...
Jason Plato Posted October 3, 2011 Share Posted October 3, 2011 why bother running such a low ride height and then have to manage the consequences ? get 80mm under the sump and all will be ok , or update the spring rates . Link to comment Share on other sites More sharing options...
6speedmanual Posted October 3, 2011 Share Posted October 3, 2011 DJ, Because settinging the suspension close to its design specification is beneficial and managing the consequenses is simple. here Peter Link to comment Share on other sites More sharing options...
anthony1956 Posted November 5, 2011 Share Posted November 5, 2011 sorry Peter I missed this reply. My blue plate was damaged by a camp site Germans' caravans concrete hump (sleeping policeman). At least that is what I am told is the reason for it being so vicious. Hard way to learn about the effect of concrete instead of tarmac. So my front wheels went up and over and by the time the underneath of the car landed on the hump, it was the blue plate bolt heads on one side that took the damage, including knocking some of the thread off from the housing itself. Later campsite ingress and egress were by means of paving stones I placed as runners to provide a path before and after the hump, so reducing it's height to something I could push the car over without anyone in it. That's my best recollection of the horrid affair. Car as of today has an ally sumpguard made from the stuff I see used on Landrovers, folded to hold spaceframe bars, but held on only with cable ties should it need to let go without taking the chassis with it. Not 100% sure about it, but not too rough here for testing and early experience. Very interested to hear about Col de Tende as I sat at the end of the tarmac on both sides a couple of months ago wondering whether to go or not, decided not given lack of sump guard. So do I gather it can be (sort of) driven in a 7? It looked to me like the cross bikers made a good job of flattening most of it, leaving ruts gullies and rocks strewn about. My sump is practically worn out, especially after the engine mount collapsed, hence addition of protection as a new sump looks like need to split the engine because of the bolts that run from top to bottom of the K series. Having seen it in bits at Minister I was unpleasantly surprised to see and be told it is stamped magnesium and very thin when I thought it was solid ally. So there you go. :-) I prefer the glued sacrifice idea, but that's not on the cards for now. Link to comment Share on other sites More sharing options...
Sheds Moderator Posted November 6, 2011 Share Posted November 6, 2011 Anthony, a sump guard tied on with tyraps isn't going to work. You may as well tie a biscuit tin lid under the car. What you want is a smooth plate that kicks up at the front, I'm not sure what I would fix it to at the front but I'd be thinking of tying it to the engine mounts and maybe the bellhousing bolts to the rear. Then when you hit anything solid it lifts the engine up as it slides over the obstacle. This does need a decent anchor at the front though, and obviously the front anchors are the most important. Link to comment Share on other sites More sharing options...
anthony1956 Posted November 6, 2011 Share Posted November 6, 2011 it's fashioned with four "hooks" , the metal is turned (panel beaten) so that the front two each hook over the front tube in front of the engine and two side ones each hook over the side tubes that run at an angle from front to rear. The tie wraps stop these turns or hooks chafing and moving about, but the elsaticity in the ally keeps the piece flexed solid away from the engine by 5mm approx and in place , needs a pic really. The front is like a skid so car will ride up it and being ally it is soft and sacrificial, I hope. I'll see if I can get a pic and see what you think. Link to comment Share on other sites More sharing options...
anthony1956 Posted November 6, 2011 Share Posted November 6, 2011 let's see if this works, taken me ages feeling a right numpt http://my.lotussevenclub.com/Pictures/myPictures/tabid/481/UserId/962/Default.aspx Seems to work, I have added some descriptive text for each of the five pics, but the text does not show unless the mouse pointer is over the picture. Edited by - anthonym on 6 Nov 2011 02:25:32 Link to comment Share on other sites More sharing options...
CageyH Posted November 6, 2011 Share Posted November 6, 2011 Without wanting to put a downer on this, I have my doubts if this will be effective. Anything solid enough to damage a sump, is likely to rip through the protection, as it is ally sheet. You are asking a lot of a piece of 2 to 3mm ally. It is likely to get deflected straight into the sump, and cause the same problem. I think you need something fairly solid, that is capable of lifting the car, or smashing the object if you want to protect the sump in this fashion. Link to comment Share on other sites More sharing options...
elie boone Posted November 6, 2011 Share Posted November 6, 2011 The ali sheet will work but you might need to replace it after 1 year of touring, what will not work is the fixation. Get some of those plastic ARB blocks to fix the ali plate onto the chassis tube, the front fixation is vital, the rear less so. Link to comment Share on other sites More sharing options...
anthony1956 Posted November 6, 2011 Share Posted November 6, 2011 well we'll see. the damage has been caused over many years and is the result of scraping over humps. Rocks on rough roads (tracks) have been the other issue. All at very low speed. If I actually hit something (like a rock etc at speed) I can accept that's a different kettle of fish. I have never bottomed out from compression (obviously must drive faster), caught the crown of the (fast) road and we don't have cat's eyes on the mainland. I have to try something because I have practically worn the magnesium (?) sump away. I'll report back what happens. I like the sound of Peter's alpine rock basher, but that is for another day. Link to comment Share on other sites More sharing options...
anthony1956 Posted November 6, 2011 Share Posted November 6, 2011 elie ARB blocks, will see if can do.thanks. Link to comment Share on other sites More sharing options...
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