wild bill Posted April 2, 2008 Share Posted April 2, 2008 Right then, 1.8 K series 188 bhp (probably a bit less now) with apollo (yes i know some people think they are a WOT) Removed Foam following a search on tech advice here. Drilled Sump gasket as instructed and in fact made the holes a bit bigger Tight right handers with larger G's (i.e with a faster than usual speed so track stylee) in other words mainly roundabouts produce drop in O/P Any suggestions? Never had a problem with the foam before but i don't want to fit it again because of potential hazard, baffle is AFAICS unproved, dry sump expensive. Do i need further gasket modding? on the next oil change (i change oil very regularly about every 2000 miles and after and before track days which i do less frequently now) having said that O/P when car warmed up is now 30 (just under if driven hard) whereas it used to run just above 20 when driven with spirit so the idle pressure has improved and the running O/P sits normal at about 60 ish Edited by - wild bill on 2 Apr 2008 20:44:38 Link to comment Share on other sites More sharing options...
Mick Day Posted April 2, 2008 Share Posted April 2, 2008 Check the oil pick-up pipe is not hard onto bottom of the sump. Difficult to tell but sometimes there are witness marks. So take the sump off & either mill the area to provide clearance or modify the pick-up with a large screwdriver in between the 3 pips (use the screwdriver to develop pips in the opposite direction between the existing pips)to allow better clearance. Have a look here & here for some pics etc. BTW I think the Hellier baffle helps prevent surge. Link to comment Share on other sites More sharing options...
Englishmaninwales Posted April 2, 2008 Share Posted April 2, 2008 I never solved this with my 1800 (except by fitting a DS). Took foam out, drilled gasket, apollo, improved pick up position, fitted a Hellier baffle (useless). Malcolm Link to comment Share on other sites More sharing options...
The Polisher Posted April 2, 2008 Share Posted April 2, 2008 I would avoid modifying the oil pickup by increasing the depth of the pips. If you think about this, although you may increase the oil flow when the sump is full of oil you will be at greater risk of sucking in air when the sump is starved. If the pips are 3mm deep you only need 3mm of oil to avoid sucking in air, if the pips are increased to 5mm deep you will be sucking in air with the same 3mm of oil in the sump. ☹️ Dave H. Mad about S77ENS Link to comment Share on other sites More sharing options...
Paul Deslandes Posted April 2, 2008 Share Posted April 2, 2008 I've no experience with K series engines but the Vx wet sump has a similar foam baffle. If these are not changed at about 6k miles they will clog. We recently had a friend's Vx in with low running oil pressure (30 - 45 psi flat out on a good day). We removed the foam, which didn't seem too bad - I've certainly seen worse -replaced it with new and, bingo, 60psi running, 30 at idle. If you don't know the history of the foam, change it. Its not a pretty solution but it does work and is better than no baffle, as you've just found out. Cue Oilyhands! Paul Link to comment Share on other sites More sharing options...
Stationary M25 Traveller Posted April 2, 2008 Share Posted April 2, 2008 In the K-series, the foam does nothing for surges in the sump - it is stuck to the underside of the block. The sump contains nothing but oil ! 7 related photos Link to comment Share on other sites More sharing options...
Paul Deslandes Posted April 2, 2008 Share Posted April 2, 2008 ohh err! wot's it for then? Link to comment Share on other sites More sharing options...
wild bill Posted April 2, 2008 Author Share Posted April 2, 2008 Yes you see no-one really knows of a solution as yet, where's Oily then, he's normally quick on this sort of thing 😬 Must drive slower round bends Link to comment Share on other sites More sharing options...
Manxseven Posted April 2, 2008 Share Posted April 2, 2008 Have you put enough oil in 🤔 Simon Caterham BEC here Link to comment Share on other sites More sharing options...
Kevsta Posted April 2, 2008 Share Posted April 2, 2008 Paul, I think that the foam is there to lower the windage from the crank....hence it is clamped to the underside of the plate and is not in the sump where the oil would be. Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted April 2, 2008 Leadership Team Share Posted April 2, 2008 I sufferred the same problem with my 1800K and managed to reduce the problem by fitting a softer (older!) spring in the oil pressure relief valve. I never really did manage to work out a way of properly explaining why it worked, but I think it has something to do with an increased percentage of the oil passing the valve and bleeding back to the sump rather than being pumped round the galleries to the top of the engine. Oil pressure was slightly reduced (around 3.75bar hot) but definately more piece of mind when driving hard. Prior to the change I had also noticed pressure issues going uphill and under hard acceleration - oil moving to the rear of the sump and exposing the pickup pipe. Stu. Link to comment Share on other sites More sharing options...
wild bill Posted April 2, 2008 Author Share Posted April 2, 2008 i think there's plenty of oil in but it was something i planned to check again tomorrow. Where's theb O/P release valve? Link to comment Share on other sites More sharing options...
Rob Walker Posted April 3, 2008 Share Posted April 3, 2008 Wild Bill, Apart from fitting a full dry sump system the only other alternative is an Accusump, this is a cylinder that has a piston and spring in it. When the engine pressurises it pushes the piston down the cylinder against the spring, if there is a drop in pressure the spring forces oil back into the system. Simple & clever idea, Merlin sell them circa £200. They are popular with the K Elise boy`s. I am surprised that you are noticing such rapid changes in oil pressure as the oil pressure sender is damped which normaly masks the problem, may be your sender is on its way out. Stu, I fail to see any beniftit in reducing the amount of oil that is pumped around the engine Rob Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted April 3, 2008 Leadership Team Share Posted April 3, 2008 I fail to see any beniftit in reducing the amount of oil that is pumped around the engine Rob, we all know that the Caterham K-Series wet sump is compromised especially on the bigger capacity engines. Unless switching to dry sump (which I eventually did) it's a trade-off of benefits/weaknesses. I found that by effectively backing off the oil pressure a little (only a little!) I had less air-scavenging issues, which is beneficial from a lubrication quality viewpoint, but obviously it would be preferable to run higher pressure! Once air is in the oil (despite using an Apollo) it takes time to get it out and the effective oil quantity is reduced (ie. some oil some froth). The system has to be balanced to enable it to run low revs (as low as tick-over) without swamping the sump and crank, and high revs pumping more oil to the top which only returns under gravity. The gravity should be a constant except that it is interfered with by cornering forces, crank wind, etc. A deep sump normally takes care of the issues, but obviously not possible in the K. The pressure relief valve only restricts the maximum pressure the system will achieve, therefore if the pumping is improved (eg by flowing the pump) this will enable better pumping efficiency and recovery from a low sump oil level. But sustained high pumping and reduction of the gravitational effect, allied with a limited system capacity will ultimately lead to starvation. Do you follow me? I'm not sure anyone else has tried this change and it would be a benefit if any resulting effect of a slightly lower oil pressure could be quantified - certainly for general road use the reduced pressure eliminated starvation issues. My car was also used on track so ultimately I had to go dry sump. Just a load of theory and maybe a load of b*llsh1t, but I thought the change through and it worked on my engine. My car had VDO gauges and unlike the Caterham branded versions, the VDO oil pressure gauge is hardly damped. This means that any slight changes in pressure, even momentarily, can be easily observed. The slightest amount of air entering the system will show a flick of the needle - I'm sure this is why later cars use such a heavily damped oil pressure gauge! Stu. Link to comment Share on other sites More sharing options...
Englishmaninwales Posted April 3, 2008 Share Posted April 3, 2008 I am surprised that you are noticing such rapid changes in oil pressure as the oil pressure sender is damped which normaly masks the problem Rob, I think earlier oil gauges (mine is a '94 car) have less damping, and minor fluctuations in the oil pressure are very noticeable. Link to comment Share on other sites More sharing options...
wild bill Posted April 4, 2008 Author Share Posted April 4, 2008 Rob I'm running a mech guage so didn't think there was a sender involved, am i wrong there? I did a level check with engine warmed and at idle and oil was at half way mark on the dip guage. I have put another half litre in and on testing this morning once warmed up problem seems to have lessened but haven't been able to do a full test on a hard enough corner yet. many thanks for everyone's input. Accusump sound like a good idea Rob, easy to fit? Link to comment Share on other sites More sharing options...
Rob Walker Posted April 4, 2008 Share Posted April 4, 2008 If you have a mechanical gauge then you do not have a sender unit and if its showing a drop off in pressure when cornering then I would believe it and do something about solving the problem. Yes the accusump is very easy to install its just a sandwich plate take off fitted under your oil filter then mount the cylinder on your scuttle. you can also add electrical solenoid valves that operate when you turn on the ignition, this instantly pressurizes the system. Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted April 5, 2008 Leadership Team Share Posted April 5, 2008 you can also add electrical solenoid valves that operate when you turn on the ignition, this instantly pressurizes the system Nice trick Rob Does it, and is it enough to pressurise an Apollo install because this is often a worry on some cars? Stu. Link to comment Share on other sites More sharing options...
Johnty Lyons Posted April 5, 2008 Share Posted April 5, 2008 At the severe risk of Pissing everyone off All this talk of apollos and Accusumps really is just skirting round the problem If you are Tracking a K or running on the road at high speeds on sticky rubber You Really need to bite the bullit and Go Dry I went through two cranks and countless Shells before i saw the light and went 3 Stage Pace Ive now run the same shells since 05 and abused the car no end. The expense can be justified in terms of lost time rebuilding engines, cost of same, and pure peace of mind. Don't think about it Just do it 😬 jj N.I. L7C AR 🙆🏻 Membership No.3927. Link to comment Share on other sites More sharing options...
Rob Walker Posted April 5, 2008 Share Posted April 5, 2008 Stu, I cannot see any reason why it would not fill up the apollo and pressurize on start up if you fit an accusump of sufficient capacity, 2pint 4pint & 6 pint are available. The apollo only drains down to equalize a level with the oil in the sump, thats about 1L at most . I would fit the 4 pint accusump. I have no experience of running one personally, but know of people that have and only had postive things to say about them. I considered fitting one to my Duratec but the Raceline wet sump is such a good design it has not been necessary Rob Rob Link to comment Share on other sites More sharing options...
Rob Walker Posted April 5, 2008 Share Posted April 5, 2008 Johnty, You have personal experience of running with an accusump ??? Please fill us in on the details. Rob Edited by - Rob Walker on 5 Apr 2008 10:45:21 Link to comment Share on other sites More sharing options...
Johnty Lyons Posted April 5, 2008 Share Posted April 5, 2008 Rob Contrary to your personal belief I'm NOT trying to get on you goat. Which I think you mostly presume. I don't and haven't used an Accusump on my car BUT I have friends who do. Thats not what I'm on about. I just feel from personal experience that going down the Apollo route and possible adding an Accusump is not the best idea for a K. I researched the options when I was having trouble and the result of my research led me to fit a Dry sump. It worked and worked well Friends who did one or other of the other options or in fact both, have a lot more plumbing in their car, a lot of expense, and not IMHO as good a solution. Thus my post I'm not arguing, just speaking from My Personal experience. Folk don't have to take my Crap advice they can and mostly Do just ignore me 😬 jj N.I. L7C AR 🙆🏻 Membership No.3927. Link to comment Share on other sites More sharing options...
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