Lord Flashart Posted July 21, 2011 Report Share Posted July 21, 2011 Since the other thread on this is getting a little long I though I'd start a new one to asks specific question. I have discovered something relevant. The car ha been left for about 48 hours and I noticed when I turned the engine over on the starter that it's now taking about twenty seconds to develop oil pressure. Also I checked the dipstick before spinning it and it was significantly higher than after turning it over. Seems like the oil filter is siphoning back somehow. Anyone ever heard of this? I'm going to look very closely at the oil filter assembly, but could this also be an oil pump problem? The pump is new and the symptoms were the same with the old but the car used to get oil pressure very quickly. Paul Quote Link to post Share on other sites
LGFromage Posted July 21, 2011 Report Share Posted July 21, 2011 Since the other thread on this is getting a little long I though I'd start a new one to asks specific question. I have discovered something relevant. The car ha been left for about 48 hours and I noticed when I turned the engine over on the starter that it's now taking about twenty seconds to develop oil pressure. Also I checked the dipstick before spinning it and it was significantly higher than after turning it over. Seems like the oil filter is siphoning back somehow. Anyone ever heard of this? I'm going to look very closely at the oil filter assembly, but could this also be an oil pump problem? The pump is new and the symptoms were the same with the old but the car used to get oil pressure very quickly. Paul Paul, It has been known for the collar on the dipstick to become loose leading to false readings of oil level. It would be useful to check. Tim Quote Link to post Share on other sites
Lord Flashart Posted July 21, 2011 Author Report Share Posted July 21, 2011 Checked that! Dipstick is fine! I'm running out of ideas now. I think I'm going to have to pull the engine out and rebuild the bottom end. I wish I'd never laid eyes on that synthetic oil! I had no problems before I put that **** in my engine. Never again! Quote Link to post Share on other sites
Smokey Posted July 22, 2011 Report Share Posted July 22, 2011 I had exactly the same symptoms, and it turned out to be sediment in the oil filter housing. Have you removed the oil filter housing, dismantled it and cleaned it thoroughly? That's what fixed my oil pressure problem (although not the oil CONSUMPTION problem, which was due to the idiot mechanic having fitted undersized rings). It's possible that the synthetic oil freed up some sediment that is causing problems in one of the passages in the filter housing. It's worth a try before you dismantle the engine. Or maybe you've already done it - I may have missed it in the previous threads. Removing the ball and spring,and cleaning them, did not fix my problem, possibly because the sediment was still caught under the ball. Quote Link to post Share on other sites
graeme Posted July 22, 2011 Report Share Posted July 22, 2011 Paul, I would put your old pump back on as thats when your pressure problems started! But check the clearances first. Cheers Graeme Quote Link to post Share on other sites
Lord Flashart Posted July 22, 2011 Author Report Share Posted July 22, 2011 Smokey, now you've caught my attention! I removed the filter today and there was a little bit of sediment outside of the filter. It was no metallic and wouldn't stick to a magnet. I cleaned the filter bowl and cleaned the relief valve which seemed clean anyway. I didn't remove the while housing from the engine and clean that though. Tomorrow I will do just that! That fault seems strange to me. I can drive a fair way before the pressure starts to drop. Today I drove the car about twenty kilometers and it was only after a sixty mph blast in the last five minutes that the pressure started to drop like a stone. I can't help thinking if it was the bearings then it wouldn't be capable of producing almost 80 psi when warm with the regulator turned up. Even when the pressure drops, if the car cools for ten minutes it's all back to normal. I'm going to look at my cooling system again as well. Today was only 15 degrees and the car is still running at the top of the temperature guage. This could also be part of the problem. Graeme, unfortunately the oil pressure problems developed when I put the synthetic oil in. I changed the oil pump at the same time I ditched the synth and refilled with mineral oil. I'm going to pull it and check the clearances anyway! Cheers for the help chaps. It's really appreciated. Hopefully you are on to something Smokey and I'll have oil pressure again tomorrow!!! Paul Quote Link to post Share on other sites
stuart Posted July 22, 2011 Report Share Posted July 22, 2011 If you have metal in the filter that doesnt stick to a magnet then it could be white metal from bearings. Hopefully not as bad as this filter extracted and then opened up from a customers 4a engine. Stuart. Quote Link to post Share on other sites
Lord Flashart Posted July 22, 2011 Author Report Share Posted July 22, 2011 Thankfully it wasn't as bad as that! Not even close in fact. The debris didn't look like white metal either. In some respects I wouldn't mind if it did look that bad. At least I'd have a clear way forward. I'm reluctant to strip the engine and re bearing every thing and then find I still have low pressure due to some other problem. I'll strip and clean the filter housing today and see what happens. If this fails I think I'll start stripping the thing down. Cheers guys Paul Quote Link to post Share on other sites
67_gt6 Posted July 22, 2011 Report Share Posted July 22, 2011 Thankfully it wasn't as bad as that! Not even close in fact. The debris didn't look like white metal either. In some respects I wouldn't mind if it did look that bad. At least I'd have a clear way forward. I'm reluctant to strip the engine and re bearing every thing and then find I still have low pressure due to some other problem. I'll strip and clean the filter housing today and see what happens. If this fails I think I'll start stripping the thing down. Cheers guys Paul I posted in your out of date thread. I think your new pump is not up to scratch, maybe vane clearances. revert to old pump and 20w50 mineral and I suspect things will be back up to normal. Andy Quote Link to post Share on other sites
Lord Flashart Posted July 22, 2011 Author Report Share Posted July 22, 2011 That's not a bad idea. I may a well try before stripping the whole engine. Cheers Paul Quote Link to post Share on other sites
BrianC Posted July 22, 2011 Report Share Posted July 22, 2011 There seem to be several possible problems here, but given all the changes of oil, filter, pump, etc, perhaps the inconsistent presuure readings are a symptom of air or sludge from the synth/non-synth oil mixture in the oil gauge pipe. Live in hope! [ I thought we had established long ago on this Forum that synthetic oil is 'not a good idea' in TRs - except possibly for racers prepared to change oil, bearings, rings, etc., far more frequently than we mortals] Quote Link to post Share on other sites
Lord Flashart Posted July 22, 2011 Author Report Share Posted July 22, 2011 I tried that yesterday Brian. I even fitted the gauge off my frogeye project and it concurred with the TR gauge. This was after allowing the line to blow a fair bit of oil through to the dash board. Today I've removed and cleaned the filter and housing. No sediment to be seen and I pulled the filter apart and there was no white metal in it like in Stuarts pics. I've removed the new oil pump and compared it with the original and the new is much tighter. A 0.005 feeler gauge slides right to the bottom easily on the oil pump when doing a vane to outer rotor test. On the new even a 0.004 is tight. So I don't think it's the oil pump. Next I'm going to remove the big ends and see what's going on in there. I have the old bearings ( bagged in order) that I removes when I fitted new pistons and liners. I may try refitting then since I'm in there. I I don't find anything I'll drop the middle main bearing and check that. Hopefully I'll actually find a definate fault. I don't mind rebuilding the thing if I find something wrong. I just don't want to pull it, rebulid it, then find it's something daft causing me grief. I'm starting to think if it was bearings I should be seeing the white metal in the filter though. I'll keep you all posted. Paul Quote Link to post Share on other sites
Lord Flashart Posted July 22, 2011 Author Report Share Posted July 22, 2011 And Brian, Trust me I'll never even let a bottle of synthetic within ten feet of any of my old cars after this! I had a good engine a week ago!! Stuff of Satan! Quote Link to post Share on other sites
Lord Flashart Posted July 22, 2011 Author Report Share Posted July 22, 2011 Well gentlemen, I've taken half the engine apart and I can't find anything wrong. The big end bearing look fine and measure about one or two thou bigger than the old ones. I removed the centre main and that looks fine with no scoring. The only thing I can see is the thrust bearings need replacing. Can't see that causing oil pressure problems though. Can anyone give me the diameter of a standard main and big end? Also the thickness of a standard bearing shell for both. I'll use a micrometer and see if there is any wear once and for all. I'm probably going to take the opportunity to rebuild the whole engine. Cheers Paul Quote Link to post Share on other sites
Lord Flashart Posted July 23, 2011 Author Report Share Posted July 23, 2011 Sitting have a glass of Scotland's finest water of life last night and pondering the TRs engine, something occurred to me. What if the high temperature reading is in fact not a red hearing supplied by an inaccurate gauge? What if the engine is overheating and this is causing the low oil pressure. I'm thinking a partial head gasket failure would cause hot running and low compression and low oil pressure. I'm pulling the head this afternoon to have a look. One question, one reason for HGF is the liners sitting too low. How would you raise them if this is the problem? Thicker figure eight gaskets? I think I might have cracked this! Paul Quote Link to post Share on other sites
graeme Posted July 23, 2011 Report Share Posted July 23, 2011 Thicker figure eight gaskets? I think I might have cracked this! Paul Paul, You got it! Thicker Fo8 gaskets are available from Revington, not sure where in Canada! Also check that the liner protrusion is equal all around the circumference, machining may be required if not. There is an instrument that you can use to check to see if there is exhaust contaminants in the cooling system, perhaps a friendly garage may check it for you. Cheers Graeme Quote Link to post Share on other sites
Lord Flashart Posted July 23, 2011 Author Report Share Posted July 23, 2011 Cheers Graeme. I'd rather use Revington than any local supplier anyway. Also allows the use of my British Bank account that the wife never looks at! I've not checked them yet but I'm starting to think it makes sense that it could all be HGF. Hopefully I'll sort it out soon!! Quote Link to post Share on other sites
Lord Flashart Posted July 26, 2011 Author Report Share Posted July 26, 2011 So it turns out it was head gasket failure. The gasket was leaking between all four cylinders and to coolant. I'm guessing that it was was very slight and that's why it was hard to diagnose. The gauge always showed that it was running hot but never boiling and even a laser thermometer only showed 65-70 degrees on the head and radiator. The leak must have been small but enough to heat the oil past where is would maintain decent pressure. It also explains why the cylinder pressures were always lower than expected. I'll get the head tested and ground flat and it should be ok. I've also bought some plastigauge and I'm going to measure the clearance on every bearing before I put it all back together. I'm ecstatic I'll finally found the source of all my problems with that engine. Only bummer is that by the time the new gasket turns up i'll be laid up from my hip replacement so it'll probably be November before I get it all done. Oh well, at least the car will be ready for the next driving season! Cheers for all the help chaps. Paul Quote Link to post Share on other sites
RogerH Posted July 26, 2011 Report Share Posted July 26, 2011 Hi Paul, well done on finding the problem. I'm sure you were ready to set light to the car in frustration. I'll be thinking of you on Monday when I go under the surgeons knife. Roger Quote Link to post Share on other sites
Lord Flashart Posted July 27, 2011 Author Report Share Posted July 27, 2011 Cheers. Roger, I'm getting sliced the following Monday so let me know how you get on. Good luck mate. Paul Quote Link to post Share on other sites
Lord Flashart Posted July 29, 2011 Author Report Share Posted July 29, 2011 Further investigation showed that the liners are slightly two high. Turns out that the steel figure of eight gaskets that Moss North America supply are way too thick. I've ordered the correct copper gaskets from Revington's. I suppose it's my fault for not checking the liner height properly. Live and learn! Paul Quote Link to post Share on other sites
RogerH Posted July 29, 2011 Report Share Posted July 29, 2011 Hi Paul, how high - are we talking a few thou. There was a thread running earlier this year whereby somebody published the liner protrusion values for the different Fo8 materials using the normal composite head gasket. You could have anything from the standard 0.004" to much much bigger without problem as the gasket would absorb it. A solid gasket is a different kettle of fish though. Roger Quote Link to post Share on other sites
Lord Flashart Posted July 29, 2011 Author Report Share Posted July 29, 2011 Actually remeasured today (without a morphine affected brain!) and they all seem to be less than 0.006 of an inch. With a straight edge over the liners I can jus get a 5 thou feeler through. I'm guessing they are probably ok which is luck as revington don't have any stock of the thinner gaskets. I just need the head gasket to turn up and I'll have it all running again. Shouldn't be too long now. I ordered it three weeks ago! I miss driving over to Sports Car supplies in Gateshead and having everything the next day! Paul Quote Link to post Share on other sites
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