oilyhands Posted October 3, 2005 Share Posted October 3, 2005 Just a note about foam baffles et al. In the past two weeks I have had occasion to remove the sumps from 3 Caterham engines suffering with low oil pressure, two were wet sump (one with Apollo) and the other was a gold-pumped dry sump system. Two of these had pickups completely full of broken up sump foam, one of them had hardly been used since the low oil pressure manifested itself and the bearings were pristine, the other had run bearings 1 and 2. The dry sumped engine had its sump sealed with Hylomar and the pickup for the scavenge pump was entirely covered/blocked with curds of solidified Hylomar that had severely restricted the pumps ability to recover oil from the sump, this had caused big-end 2 to be wiped out. Can I suggest that i) On wet sumps, either dont use the sump foam or replace it every 6 months to enure it doesn't harden and break up, there are modifications you can make to the gasket to improve the oil drain and concentrate it around the pickup. ii) When fitting dry sump pans DO NOT USE a regular or silicone sealant, use only Loctite 574 anaerobic flange sealant or similar. If you use an anaerobic sealant then it will harden only *in* the joint, any excess will be simply washed away and will not harden or gather at the pickup. Excess amounts of traditional or silicone sealants will harden, fall into the sump and cause mayhem. Please, please ignore the instructions with the dry sump system to use silicone sealant, it is entirely the wrong thing to use anywhere on an engine where it's debris can enter the engine void/sump. Oily Edited by - oilyhands on 3 Oct 2005 09:30:07 Link to comment Share on other sites More sharing options...
Myles Posted October 3, 2005 Share Posted October 3, 2005 replace it every 6 months Or 200 miles in my case... ☹️ Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Support Team Shaun_E Posted October 3, 2005 Support Team Share Posted October 3, 2005 Hands up - the dry sumped described engine above is mine ☹️. I was gobsmacked at how badly blocked the pickup was . Before everyone shouts "I told you so" it wasn't until after I had fitted my sump that I read the advice not to use silicone. I then removed it and used blue hylomar instead thinking that would be OK - it patently is not. Luckily my engine was being stripped prior to upgrading but it probably wouldn't have held on much longer. The engine obviously had other issues as well - the oil pump was completely knackered (some hard debris by the look of the damage) and a piece of debris has also found it's way through my gold scavenge pump. Luckily Oily was able to clean up the scavenge pump and it should be fine. I learned a hell of a lot watching my engine being taken apart and will be there for the build . My advice is listen to Oily. Yellow SL #32 Link to comment Share on other sites More sharing options...
caterhamnut Posted October 3, 2005 Share Posted October 3, 2005 *thumbup*thanks Oily www.mycaterham.com here 87,756 miles in 4 years - 1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
Pelico Posted October 3, 2005 Share Posted October 3, 2005 Cheers Oily, Can you say more about the modifications to the gasket. I assume you mean the large (wolverine ?) sump gasket. Does anyone have any news on modifications to the Hellier baffle plates. I know some were experimenting with drilling them, fore to aft I think ? Thanks, Peter Link to comment Share on other sites More sharing options...
Bricol Posted October 3, 2005 Share Posted October 3, 2005 Probably the most important word here is "Excess". Whatever sealant you use, you are joining two precision (hopefully) components together - not sealing a bath to a wall. So only a THIN smear is required - and when I say thin - just a smear down the middle of one of the surfaces so when the joint is joined, it can spread slightly without squeezing out. If you see it squeezing out on the outside, you've used too much and it will also be squeezing out on the inside. Time to dismantle and re-do. I learnt the hard way with hylomar and a Triumph engine quite a long time ago. As for the foam - I wonder if oil choice has any bearing on the foam degradation? I've only used Comma Synergy stuff (as recommended by Caterham) and in 15,000 miles, I've not noticed any foam breakup. Old foam was black and dirty (of course) but nearly as flexible as the replacements, certainly not brittle enough to break-up with flexing around. I don't know if my car use has a bearing either - mine tends to sit for months doing nothing (due to working here, there and everywhere) and then get a short blast of hard-work - 2170 miles in one week the week before last charging all over the Alps upsetting fast bike riders. Bri Edited by - Bricol on 3 Oct 2005 11:11:36 Link to comment Share on other sites More sharing options...
oilyhands Posted October 3, 2005 Author Share Posted October 3, 2005 Bricol, I agree that it is excess sealant that ends up in the pickup, however if the sealnt is anaerobic then the problem simply doesnt occur. It's also very difficult to know, especially for a novice what amounts to excess and what doesn't. To be completely successful any sealant will need to be applied in slight excess. There will always be those who dont have a problem, that is the nature of the issue, but surely it is better to spend the extra £15 on a sealant that you *know* can never give a problem rather than spend 50 times that on a premature engine rebuild. I have seen sufficient number of broken up foam baffles to know that there is no degree of certainty with those, even with recomended oils the baffle has been known to disintegrate at lower than the recommended change interval. I will take some photos of the modified sump (large wolverine type) gasket the next time I modify one, the trick is to encourage drain of the oil into a concentrated stream, right above the pickuo, this involves drilling some small holes in the gasket on the lower side so that the drain from behind the gasket where a wedge of oil normally forms is direct rather than spilling over the gasket 'wall'. That way the whole of the drain from that lower side of the engine cavity is concentrated where it is needed. I have tried modifying the sump baffle to allow oil to flow into the pickup are from the back and front of the sump but this had little or no affect. since drilling the sump gasket and removing the baffle on two engines, things have improved significantly. I'll publish the pictures of the gasket mods as soon as they are taken. Oily Link to comment Share on other sites More sharing options...
Myles Posted October 3, 2005 Share Posted October 3, 2005 I wonder if oil choice has any bearing on the foam degradation? Well (and this is all in the archives, but worth repeating here...)... I ran with the foam for almost 18k in total - all with Halfrauds 'Fully Synth'. I changed the foam once in that time, IIRC and didn't have any significant issues (few bits of debris, but nothing to worry about). Then we built the PSC engine (with foam) and I filled it with cheap non-synth cr&p for running in. Sticking to the facts, the foam *completely* dissolved within a very short time (ISTR I noticed a drop in OP around the 70 mile mark...) - certainly less than 400 miles. The result was damaged bearings... The point was made at the time by Oily that although most people get away with using the foam for mile after mile, there are many, many cases where the foam has failed - and no real consistency of how and when it happens. It's an unpredictable time-bomb. Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
bat flattery Posted October 3, 2005 Share Posted October 3, 2005 ...so regarding the sump foam, is the advice to take it out and don't replace it with anything - this would be for general road only use, by the way? Just wondering what to do for the best - I have done 8500 miles on the original foam in just under 2 years..... Peter Red Roadsport SV FP53FHB Link to comment Share on other sites More sharing options...
prs Posted October 3, 2005 Share Posted October 3, 2005 I'm now running a CC dry sump and had problems getting a decent oiltight seal using Loctite 574 even though both mating surfaces looked perfect. My final solution was to use a wet sump gasket and cut off the surplus, I've now done several thou and it seems ok with no seepage etc. Phil S7SVN Link to comment Share on other sites More sharing options...
Dobuy Posted October 3, 2005 Share Posted October 3, 2005 I use the Ford (blue-black) sealant as recommended by Pete McEwan at Raceline, he swears by it, no idea what spec it is Duratec SV, built in Dubai Link to comment Share on other sites More sharing options...
martinwhitcher Posted October 4, 2005 Share Posted October 4, 2005 Great post Oily, Top advice as always...... Guess if people do not want to take it, they would probally end up at yours anyway Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 207 Edited by - Martin Whitcher on 4 Oct 2005 13:11:11 Edited by - Martin Whitcher on 4 Oct 2005 13:11:21 Link to comment Share on other sites More sharing options...
captain chaos Posted October 4, 2005 Share Posted October 4, 2005 I use a black sealant as recommended by vauxhall (it is one of their own parts). It's bloody difficult to get off but ceratinly only a small amount is needed to do the job. How can one tell if it's Anaerobic?...is that a bit like Oz Aerobics on sky! 😬 Link to comment Share on other sites More sharing options...
Myles Posted October 4, 2005 Share Posted October 4, 2005 Easy( ) - squirt some onto a surface that is open to the air and see if it sets... Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Ash.Bailey Posted October 4, 2005 Share Posted October 4, 2005 😬 Halfords "blue" sealant is anerobic . Anerobic sealant on sets in the absence of air (doh) so squirt some on the workbench / kitchen table / toilet seat and see if it cures or sets over night Captain - dont dream of jumping into bed with those Ozzy aerobics instructors ........let me tell you , you will be very demoralised Edited by - wonkycustard on 4 Oct 2005 13:31:33 Link to comment Share on other sites More sharing options...
captain chaos Posted October 4, 2005 Share Posted October 4, 2005 I needed a 'tongue in cheek' smilie for my Anerobic comment ...Wonky, I see your another fan of Oz Aerobics... I might get totally demoralised...but what a way to go! Link to comment Share on other sites More sharing options...
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