Panch Posted August 6, 2019 Report Share Posted August 6, 2019 Hi all, I seem to have a leak on every bolt holding the aluminium sump on place.. It looks as though the oil is seeping down the thread and then forming a drop on the head of each bolt (see pic). I've tried removing the bolts and putting thread sealer on each along with adding a dowty washer, but that still hasn't seemed to have cured the issue.. anyone else encountered this and found a way of making it leak proof?? Panch Quote Link to post Share on other sites
Waldi Posted August 6, 2019 Report Share Posted August 6, 2019 Hi Panch, Are you using spring washers or flat washers? They look like steel washers. It is best to use copper flat washers with some sealant. Waldi Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Hi Waldi, thanks... I've tried spring, flat and now Dowty.. not sure what they're called over your way, but they're the flat steel washers with the rubber seal on the inside. None of them seem to be working sadly..! I've also tried a couple of thread sealants too, and that's not working either.. Panch Quote Link to post Share on other sites
Mike C Posted August 6, 2019 Report Share Posted August 6, 2019 Loctite 577 https://www.henkel-adhesives.com/au/en/product/thread-sealants/loctite_577.html#Features and Benefits Quote Link to post Share on other sites
RogerH Posted August 6, 2019 Report Share Posted August 6, 2019 Hi Panch, I'm sure you have looked but!!! have you looked at the front of the engine for other leaks. Timing chain case is a usual villain. Roger Quote Link to post Share on other sites
Kevo_6 Posted August 6, 2019 Report Share Posted August 6, 2019 Wasn’t the alloy sump notorious for small pin hole leaks in the casting. Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Thanks Mike... but I'm using Permatex High Temp thread sealant already, and in the past I've found that it seals absolutely anything... have you used the Loctite 577 before in High temp environments and had success? Thanks Roger, yes checked everywhere else that it might be coming from and it definitely seems to be coming down the threads... even the bolts right at the back on the sump have the same issue! I wasn't aware that the alloy sumps had an issue with leaks? Anyone else encounter this as well then? It's pretty much a brand new sump from SC so I'd hope that they would have resolved any historical issues by now?? Panch Quote Link to post Share on other sites
RogerH Posted August 6, 2019 Report Share Posted August 6, 2019 Hi Panch, just a few years ago (4 or 5) there were posts about porous castings in both the sump and rocker covers. However that would tend to be in a specific area and probably not cover all the screw heads. Roger Quote Link to post Share on other sites
Steves_TR6 Posted August 6, 2019 Report Share Posted August 6, 2019 If they are all leaking i’d question the gasket? surely the gasket should stop oil getting to the bolts? steve Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Thanks Roger... mmm... Steve, you may have a point there... I wonder... Panch Quote Link to post Share on other sites
JochemsTR Posted August 6, 2019 Report Share Posted August 6, 2019 (edited) 24 minutes ago, Steves_TR6 said: if they are all leaking i’d question the gasket? Yes! Did you put sealant on the gasket (both sides) and around the holes ? Jochem Edited August 6, 2019 by JochemsTR Quote Link to post Share on other sites
Nigel Triumph Posted August 6, 2019 Report Share Posted August 6, 2019 I've had a similar problem with coolant leaking around the water pump mounting studs, which are fitted to an aftermarket alloy impeller housing on my 2.5 litre GT6. Refitting the studs with Loctite has fixed the leak, as Mike C recommends above. Nigel Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Jochem, I didn't fit the sump so not sure what was done sadly.. Thanks Nigel.. think I might just redo the gasket and then use Loctite as well.. belt and braces approach.. Panch Quote Link to post Share on other sites
colin3511 Posted August 6, 2019 Report Share Posted August 6, 2019 Panch, As Steve has said, the bolts and thread areas are irrelevant. The correct gasket with a good quality sealant will solve your issue. The consistency of the leaks from every bolt confirms the issue is the gasket and its sealing method. Colin Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Thanks Colin... sounds like another job for the weekend then... Panch Quote Link to post Share on other sites
Steves_TR6 Posted August 6, 2019 Report Share Posted August 6, 2019 (edited) Let is know how you get on Panch! be sure to clean the mating surfaces thoroughly, perhaps whoever fitted the alloy sump wasn’t thorough enough. also, i wonder what the correct torque figure is for the sump bolts with the alloy sump?, low torque setting on the steel sump is partly to protect the sump flange from distortion. Also beware the allow bridges front and back, these strip their threads easily ! steve Edited August 6, 2019 by Steves_TR6 Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Great... thanks Steve.. Will need to do a bit of a search I think to find out the correct torque settings for alloy... otherwise will just go with standard I think.. Panch Quote Link to post Share on other sites
John L Posted August 6, 2019 Report Share Posted August 6, 2019 All the side bolts are away from the oil, the only ones you need to seal with copper washers are the 4 I think in the aluminium bridge piece at the front and the rear of the engine, these do go into the oil. John Quote Link to post Share on other sites
astontr6 Posted August 6, 2019 Report Share Posted August 6, 2019 6 hours ago, Panch said: Hi all, I seem to have a leak on every bolt holding the aluminium sump on place.. It looks as though the oil is seeping down the thread and then forming a drop on the head of each bolt (see pic). I've tried removing the bolts and putting thread sealer on each along with adding a dowty washer, but that still hasn't seemed to have cured the issue.. anyone else encountered this and found a way of making it leak proof?? Panch 6 hours ago, Panch said: Hi all, I seem to have a leak on every bolt holding the aluminium sump on place.. It looks as though the oil is seeping down the thread and then forming a drop on the head of each bolt (see pic). I've tried removing the bolts and putting thread sealer on each along with adding a dowty washer, but that still hasn't seemed to have cured the issue.. anyone else encountered this and found a way of making it leak proof?? Panch Hi Panch, That sump looks to me to be to be a gravity casting if so this type of casting is prone to be porous when cast in aluminium? Are there any other oil patches on your sump i.e. between the ribs. You may have to have the casting vacuum sealed, a common Aerospace procedure to cure this sort of problem. Bruce. Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Oh really?? That's interesting. I'll look further into that then Bruce.. thanks.. I'm wondering if I should just go back to the standard sump!! Panch Quote Link to post Share on other sites
Chilliman Posted August 6, 2019 Report Share Posted August 6, 2019 For what it's worth I've had a couple of these sumps from new and they were both porous...but I agree with the others, I think it is more likely a gasket issue, plus of course you can't use the original bolts as they are too short Quote Link to post Share on other sites
Richard M Posted August 6, 2019 Report Share Posted August 6, 2019 11 hours ago, Panch said: Hi all, I seem to have a leak on every bolt holding the aluminium sump on place.. It looks as though the oil is seeping down the thread and then forming a drop on the head of each bolt (see pic). I've tried removing the bolts and putting thread sealer on each along with adding a dowty washer, but that still hasn't seemed to have cured the issue.. anyone else encountered this and found a way of making it leak proof?? Panch Hi Panch, I have the same problem but only on 3 bolt heads two on drivers side of engine second & third one back from timing case & one on left side towards the bell housing cured this one with sealant, but unable to stop the other two from leaking. My thoughts are that it must be the gasket that has not been fitted correctly but now hearing your problem l am not so sure. What grade oil are using ? since l changed my oil that must of been to thin & replaced with 20/50 it has reduced the leak. Quote Link to post Share on other sites
Panch Posted August 6, 2019 Author Report Share Posted August 6, 2019 Richard, I'm using Classic Oils 20w/50 so I don't think it's the oil. I'm now tossing up between it being the gasket and/or the porosity of the aluminium itself based on comments above. The thing is, if I've got to take the sump off to redo the gasket, and then I find it's the sump itself once I've reassembled everything, I'm going to wish I'd just swapped the sump when I was doing the gasket!! Thoughts on whether I just go back to a standard sump? I thought the additional cooling and the capacity would be a bonus with the aluminium sump, but not at the expense of my garage floor.. Panch Quote Link to post Share on other sites
Mike C Posted August 7, 2019 Report Share Posted August 7, 2019 (edited) If you take the sump off run a straight edge along the mating faces to make sure the gaskets are being compressed properly. I went off finned sumps decades ago after reading an article by the late Phil Irving in a book published by Repco/Brabham around 1970 - the didn't improve oil cooling during engine operation much at all unless the sump also had internal ribs. Can't find the Repco reference but this link has Phil's ideas from his book "Motorcycle Engineering" https://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&cad=rja&uact=8&ved=2ahUKEwikwdbD1e_jAhUGA3IKHe8RB-cQFjAKegQIBBAC&url=https%3A%2F%2Fwww.perfvair.com%2Fapp%2Fdownload%2F5712740%2Fperformancecorvairs_Sample.pdf&usg=AOvVaw1XabJ5_BAq-_iEsNFylDjg Edited August 7, 2019 by Mike C Quote Link to post Share on other sites
Waldi Posted August 7, 2019 Report Share Posted August 7, 2019 If the casting appears to be porous: Porous castings can be made leak-tight by impregnating with water glass, which is cheap, but I do not know if this still works once the metal is contaminated with oil. Waldi Quote Link to post Share on other sites
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