Richard71 Posted July 21, 2019 Report Share Posted July 21, 2019 Hello All, I've read here on the forum that some Spin On Oil Filter Adaptors cause reduced oil pressure. Having exhausted every other possibility I now suspect this could be my low oil pressure problem. Does anyone know what the problem with some of these maybe, is there a casting issue to look for when I remove it for examination? Thanks in advance. Richard. Quote Link to post Share on other sites
jerrytr5 Posted July 23, 2019 Report Share Posted July 23, 2019 There is an issue with some versions not sealing to the block correctly. I understand later designs have a sprung centre to cater for differences with the engine block, but I thought that was to resolve external leaks rather than pressure issues. I'm sure somebody can elaborate who has seen the different versions. Jerry Quote Link to post Share on other sites
Waldi Posted July 23, 2019 Report Share Posted July 23, 2019 41 minutes ago, jerrytr5 said: There is an issue with some versions not sealing to the block correctly. I understand later designs have a sprung centre to cater for differences with the engine block, but I thought that was to resolve external leaks rather than pressure issues. I'm sure somebody can elaborate who has seen the different versions. Jerry As Jerry says, there is a risk of internal bypassing (which would not affect oil pressure but will result in poor oil filtration. This because with the central nut both the external seal (block ring in machined groove) and internal seal (which sits against the inner machined surface of the block) can be on different heights. Modern adaptors have a spring loaded inner gasket ring, which is pushed to the block by a spring. If you carefully look at the design before installation so you understand how it works you reduce the risk of wrong installation a lot. Regards, Waldi Quote Link to post Share on other sites
RogerH Posted July 23, 2019 Report Share Posted July 23, 2019 Hi Richard, not heard of the spin on filter affecting oil pressure but the very early ones (my one) did not seal well causing external leaking. I sorted my own problem. Later ones are better. Can you elaborate on your low oil pressure problem or point to a post containing it. Roger Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 Jerry, Waldi, I definitely have the later type conversion with the spring. Roger, I can't find the post right now, but it was something Pilkie (Dave Pilkington) mentioned on a topic about them causing low or nil (his exact words) oil pressure. My problem is......cold engine idle around 70psi, hot engine idle almost zero, but not low enough for the warning light to illuminate but low enough to concern me. Engine has around 3000 miles since rebuild, I built it myself so I know all internal gallery plugs etc are in place. I've recently changed the oil pump and relief valve for those supplied by Chris Witor, no change. Tried differing brands of oil, Valvoline VR1 and latterly Castrol Classic (Castrol even lower pressure), differing oil filters, Crossland & K&N, still no improvement. All I can think of left to look at is the spin-on oil filter head, if I have time after work tonight I'll remove it and see if there's anything untoward. New seal kit for the filter head in the post from MOSS. Richard. P.S. The first 1000 miles I ran with the external rocker feed, removed it for the past 2000 miles no difference in pressure, took the rocker cover off at the weekend and there's evidence of a good healthy oil supply to the top end/rocker gear. Richard. Quote Link to post Share on other sites
RobH Posted July 23, 2019 Report Share Posted July 23, 2019 Obvious question perhaps - but are you sure the oil pressure gauge is telling the truth ? Quote Link to post Share on other sites
Pete R Posted July 23, 2019 Report Share Posted July 23, 2019 My TR6 went through a couple of sets of bearings, with oil pressure dropping low very quickly, before I realised the rubber seal of the spin on filter was not mating to the block as it was a smaller diameter. I think Moss note the fact some blocks are different in their catalogue/web site. Got another spin on adapter and all was well. Suggest you take your adapter off and check, as this may be the reason. Pete Quote Link to post Share on other sites
duncan Posted July 23, 2019 Report Share Posted July 23, 2019 Richard, do you have the adaptor for the oil cooler ? If not, then see above. If so, is there a pipe between the inlet & outlet ? If not, then no oil circulation. Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 23 minutes ago, RobH said: Obvious question perhaps - but are you sure the oil pressure gauge is telling the truth ? Yes Rob, I should have said, these pressures are backed up with an annually calibrated gauge mounted on a Tee piece by the pressure switch. 6 minutes ago, Pete R said: My TR6 went through a couple of sets of bearings, with oil pressure dropping low very quickly, before I realised the rubber seal of the spin on filter was not mating to the block as it was a smaller diameter. I think Moss note the fact some blocks are different in their catalogue/web site. Got another spin on adapter and all was well. Suggest you take your adapter off and check, as this may be the reason. Pete Will check and report back hopefully this evening. 5 minutes ago, duncan said: Richard, do you have the adaptor for the oil cooler ? If not, then see above. If so, is there a pipe between the inlet & outlet ? If not, then no oil circulation. No Duncan, no oil cooler connections on my adaptor. Quote Link to post Share on other sites
ntc Posted July 23, 2019 Report Share Posted July 23, 2019 If you look at the retaining bolt the spring closer tab is threaded this can and will climb the bolt you must stop this as you fit the adapter or you will loose pressure Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 (edited) Hello All, Filter head now removed (see pic). The inner seal is a very very poor fit in it's recess, in fact it doesn't fit at all!!! The internal diameter of the seal is too narrow. When the head was removed the seal was stuck to the block, but not in the position you would hope it to be. Did this happen during removal of the head? Hmmm, don't think so! My assumption, it was like this when I fitted it, how did this happen? Could only have been carelessness on my part. Can this be the cause of my low oil pressure contrary to what Jerry suggests? 2 hours ago, ntc said: If you look at the retaining bolt the spring closer tab is threaded this can and will climb the bolt you must stop this as you fit the adapter or you will loose pressure Neil, I worked the bolt with a spanner on the bench, it's locked tight on the spring tab and the whole centre section rotates independently of the filter head. So can't see an issue there. But thanks for the pointer. New seal kit should be here tomorrow. Thanks to all for your input thus far. Richard. Edit..... If as said the centre section rotates independently of the head, then when tightening the bolt the seal will rub & twist against the block for maybe the last half turn or so. Much like what happens with an ordinary spin-on filter, but this seal is flimsy compared with that on a spin-on filter. Maybe an issue, especially if it's ill fitting. Edited July 23, 2019 by Richard71 Additional though. Quote Link to post Share on other sites
ntc Posted July 23, 2019 Report Share Posted July 23, 2019 Richard look closely and you can see the tab is already starting to climb the bolt as I said Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 11 minutes ago, ntc said: Richard look closely and you can see the tab is already starting to climb the bolt as I said Just looked, that tab is solid tight on the bolt at the top of the thread. While manipulating trying to prove what you're suggesting I appear to have broken two of the smallest welds I've ever seen, they were holding the tab on the centre section. Richard. Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 I think I'm understanding what you're saying now Neil. Should it look more like what's in the attached pic...….but with so much free thread, how do we determine the height of the inner section? Anyone got install instructions for this apparatus? Richard. Quote Link to post Share on other sites
stillp Posted July 23, 2019 Report Share Posted July 23, 2019 Have you still got the standard oil filter to try, so you can see if it is the spin-on that's causing your pressure issues? Pete Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 15 minutes ago, stillp said: Have you still got the standard oil filter to try, so you can see if it is the spin-on that's causing your pressure issues? Pete Hi Pete, I'm now sure it's the filter head (fitment) was the problem. As Neil pointed out above, the tab was threaded onto the stud where it's meant to be floating. This tab it would appear should float on the un-threaded section of the bolt. In my case it didn't. Was it like this out of the box, or was it my carelessness, either way I should have paid more attention when installing it. I'll re-fit it when the new seal kit arrives and report back. Richard. Quote Link to post Share on other sites
Waldi Posted July 23, 2019 Report Share Posted July 23, 2019 Hi Richard, good you found it. I have found a copy of the (Moss) adapter fitiing instructions, 3 pages. If you pm me your mail adress, I will send them to you. There is no mention about the location of the tab. Do not forget to inspect (replace) the thin O-ring between the inner and outer adapter. Oil it before assembly to avoid it is damaged at installation. I hope this will solve your issue, as I do not understand why a restricted cross-sectional area should give a high pressure with cold oil but a very low pressure hot. Regards, Waldi Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 Hi Waldi, PM sent. Cant answer why the restriction would give this low oil pressure, but a definite problem as been found, and once the filter head is back on we'll know. Richard. Quote Link to post Share on other sites
Waldi Posted July 23, 2019 Report Share Posted July 23, 2019 Very good Richard, if the issue persists (I hope not off course) I would remove the oil relief valve (again, sorry), and check it is not sticking / binding. Mine did, and by grinding a little bit from the disk It got more lateral clearance in the machined pocket in the block. Are you able to tell why the relocated tab would cause the issue? In other words: what happens exactly? Alternatively Neil (NTC), can you maybe enlighten my darkness? Thanks, Waldi Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 (edited) Hi Waldi, If the threaded tab is allowed to thread up the bolt it can & will prevent the inner seal and it's carrier from mating with the engine block. This I expect will reduce flow & pressure, I can't understand why it's alright at cold temperature. Which asks the question, why have MOCAL threaded this part of the bolt, these threads are surplus to requirements and as I may have discovered a real problem area. Richard. Edited July 23, 2019 by Richard71 Quote Link to post Share on other sites
Waldi Posted July 23, 2019 Report Share Posted July 23, 2019 Thank you Richard. My understanding is that if the inner part lifts (goes further from the block), oil will be by-passing the filter, which should not affect pressure (flow). Maybe the issue is at the other end of the inner part? I should have made a sketch when I installed mine;) Waldi Quote Link to post Share on other sites
Richard71 Posted July 23, 2019 Author Report Share Posted July 23, 2019 4 minutes ago, Waldi said: Thank you Richard. My understanding is that if the inner part lifts (goes further from the block), oil will be by-passing the filter, which should not affect pressure (flow). Maybe the issue is at the other end of the inner part? I should have made a sketch when I installed mine;) Waldi Agreed, But also....within the filter/head we have oil flowing in two different directions and these two different paths of flow should not be allowed to cross, in my case that's what's been happening. You might say I've had a short circuit in my filter head . Richard. Quote Link to post Share on other sites
ntc Posted July 23, 2019 Report Share Posted July 23, 2019 43 minutes ago, Richard71 said: Hi Waldi, If the threaded tab is allowed to thread up the bolt it can & will prevent the inner seal and it's carrier from mating with the engine block. This I expect will reduce flow & pressure, I can't understand why it's alright at cold temperature. Which asks the question, why have MOCAL threaded this part of the bolt, these threads are surplus to requirements and as I may have discovered a real problem area. Richard. Lets give you a clue, which path to you think the oil would take given half a chance when hot also think of the spring load. Quote Link to post Share on other sites
Waldi Posted July 23, 2019 Report Share Posted July 23, 2019 Thank you Neil. I think it does not matter much what the spring load is, but I guess I’m wrong here. Unfortunately I do not remember what the innards look like. If I recall correctly, the spring’s purpose is to provide sufficient force to press the inner part of the adapter and flat rubber ring to the machined engine boss. It is an internal seal. If it would not seat properly the oil would by-pass the filter cartridge, which will not result in reduced flow or pressure ( actually a bit more of both). And by screwing the tab more “in” the spring load (force) increases, but is this bad? Think I need another clue:) Regards, Waldi Quote Link to post Share on other sites
DRD Posted July 24, 2019 Report Share Posted July 24, 2019 17 hours ago, Richard71 said: Hi Waldi, If the threaded tab is allowed to thread up the bolt it can & will prevent the inner seal and it's carrier from mating with the engine block. This I expect will reduce flow & pressure, I can't understand why it's alright at cold temperature. Which asks the question, why have MOCAL threaded this part of the bolt, these threads are surplus to requirements and as I may have discovered a real problem area. Richard. Richard, I had exactly the same problem as you when I first tried fitting it - the instructions don't make it very clear. I think the idea of using a floating washer was to allow for variability in different engine blocks as the original design, without the floating washer, didn't always fit properly. Darren Quote Link to post Share on other sites
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