EdMcC Posted August 17, 2009 Report Share Posted August 17, 2009 After 28 years in storage my TR4A is now legally back on the road. It sailed through its MOT test earlier today helped by a new steering rack, brake calipers, clutch and brake master cylinders etc. Leaving aside the fact that the electrics died (temporarily) and the starter motor jammed as I was just about to it drive it on to the ramp, my worry now is the oil pressure when hot....20lbs when running. It never stays near the mid-way 50 lb mark when hot and driving. Is catastrophe around the corner? Quote Link to post Share on other sites
jobster Posted August 17, 2009 Report Share Posted August 17, 2009 20 and around 50lb at what rev's? 20lb @ stationary is nothing to worry about, not even 50lb when running > 3000- 4000rpm is strange. Quote Link to post Share on other sites
EdMcC Posted August 17, 2009 Author Report Share Posted August 17, 2009 20 and around 50lb at what rev's? 20lb @ stationary is nothing to worry about, not even 50lb when running > 3000- 4000rpm is strange. It's about 50 when hot for the first few miles, then steadily drops to, and settles at, 20 at 2500/3000rpm when hot. Quote Link to post Share on other sites
littlejim Posted August 18, 2009 Report Share Posted August 18, 2009 If it's 20 lbs when you are still driving, having started at 50, that used to mean the big ends were going in the old days. The pressure leaking past the bigger than original space in there when everything has got nice and hot. Hope that I'm wrong for your sake. Quote Link to post Share on other sites
BrianC Posted August 18, 2009 Report Share Posted August 18, 2009 If it's 20 lbs when you are still driving, having started at 50, that used to mean the big ends were going in the old days. The pressure leaking past the bigger than original space in there when everything has got nice and hot. Hope that I'm wrong for your sake. Oh how that stirs some memories. My first TR3A displayed these symptoms in the early '70s and finally decided to break a shell a couple of hundred miles from home, fully loaded with camping gear, etc., whilst en route from a weeks camping in the Lake/Peak Districts to meet our girlfriends in South Wales. We removed the plug lead from the offending cylinder and managed to limp off the motorway and into the nearest town late at night. I spent a night in the car outside the local police station (they wouldn't let me sleep in a cell ), whilst my mate hitched home to pick up my Vitesse and a tow-rope. The following morning, we towed the TR south and parked it on a housing estate in Shrewsbury (would one do this today? ). Meanwhile, the Vitesse had suffered from the towing job and the water pump was leaking sufficiently to require the radiator topping-up every 10 miles or so. Still, we made it, and had our week in Wales and picked up the TR on the way home. Despite the water problem, we managed to tow at speeds well in excess of the legal limit and even got some amused smiles and waves from passing police cars. Those days were certainly different! One of those bad occasions when you say "One day we'll look back on this and laugh". So true, but I wouldn't recommend it - check the bottom end soon (or don't go too far from home ) Quote Link to post Share on other sites
TR 2100 Posted August 18, 2009 Report Share Posted August 18, 2009 It's about 50 when hot for the first few miles, then steadily drops to, and settles at, 20 at 2500/3000rpm when hot. When you say "when hot", I assume you are refrring to the water temperature. Oil takes much much longer to reach a normal operating temperature. While I agree with BrianC that you need to check the bottom end first, that is not always the solution. Long time ago, I had my engine bottom end rebuild and my oil pressure was still even lower than yours. I went through the relief valve and oil pump rotor as best I could - never did find the actual cause as someone drove into the back of me and wrote off the car. AlanR Quote Link to post Share on other sites
Richardtr3a Posted August 18, 2009 Report Share Posted August 18, 2009 This is an extreme answer. Quote Link to post Share on other sites
67_gt6 Posted August 18, 2009 Report Share Posted August 18, 2009 Hi, the first thing you should do is remove your oil pressure relief valve and make sure it is not partially held open by a bit of dirt - this can give the symptom of low pressure. Give it a good clean and replace, easy job. Andy Quote Link to post Share on other sites
EdMcC Posted August 18, 2009 Author Report Share Posted August 18, 2009 (edited) And to think I entertained a notion of driving several hundred miles to Goodwood next month! I hope it's the pressure relief valve but I have a gloomy feeling......... Edited August 18, 2009 by EdMcC Quote Link to post Share on other sites
ianc Posted August 19, 2009 Report Share Posted August 19, 2009 It is possible that the surface of the ball bearing in the pressure relief valve has become pitted/damaged. I advised a recent correspondent with similar symptoms to remove his ball (ouch!), and he found just this problem. With a new ball, he was as good as new! Ian Cornish Quote Link to post Share on other sites
peterm Posted August 19, 2009 Report Share Posted August 19, 2009 Hi, Yes, it certainly could be a problem related to your oil pressure relief valve. Once you've checked for any obstructions beneath the ball, and/or condition of the ball, check the length of the spring. The correct length is given in the manual. Also, when replacing the ball, give it a sharp tap to make sure it is properly seated. Best of luck, peterm Quote Link to post Share on other sites
EdMcC Posted August 19, 2009 Author Report Share Posted August 19, 2009 Getting this laptop covered in oil but who cares....just finished in the garage to find that the pressure relief valve was kaput! Some rudimentary cleaning/freeing up has resulted in a much improved oil pressure reading. Phew! Thanks to all. Quote Link to post Share on other sites
Don Elliott Posted August 20, 2009 Report Share Posted August 20, 2009 If you are not already using 20W50 oil, you could switch to the more viscous grade and gain a few more PSI oil pressure when the engine gets hot. I am using Castrol 10W30 in my 1958 TR3A and get acceptable (normal) oil pressures. I re-built the engine in 2007 and have driven 8,000 miles since then without needing to add any oil between oil changes. Quote Link to post Share on other sites
EdMcC Posted March 15, 2010 Author Report Share Posted March 15, 2010 (edited) A lot has happened since last August when I started this thread. Suffice to say the engine is now on the bench dismantled. The crankshaft is scored and needs reground (it seems to have been reground once before); plus new main and conrod bearings and oil pump are needed. I'm not sure whether to do the pistons/liners, valvegear etc when the engine is out or leave well enough alone. I see lots of £ signs ahead for all this - any advice welcome. Edited March 15, 2010 by EdMcC Quote Link to post Share on other sites
Ade-TR4 Posted March 16, 2010 Report Share Posted March 16, 2010 Hi Did you do a compression test before dismantling? If not, then check for glazing/ damage/ lipping of the bores. If they're OK and you don't want to take the opportunity to increase the capacity , then you could keep costs down and soldier on with the same set. I'd probably stick a new set in whilst it's on the bench and in pieces, unless I knew that they were "as new". A set of P&Ls is about £400-500, reworked head approx £500-700 Tricky decision... Ade Quote Link to post Share on other sites
i8pig Posted March 16, 2010 Report Share Posted March 16, 2010 Hi Ed, I have just posted some stuff on the for sale and wanted bit that you might be interested in. Steve Quote Link to post Share on other sites
88V8 Posted March 16, 2010 Report Share Posted March 16, 2010 A lot has happened since last August when I started this thread. Suffice to say the engine is now on the bench dismantled. The crankshaft is scored and needs reground (it seems to have been reground once before); plus new main and conrod bearings and oil pump are needed. I'm not sure whether to do the pistons/liners, valvegear etc when the engine is out or leave well enough alone. I see lots of £ signs ahead for all this - any advice welcome. Check the cam and followers, and the rocker shaft. They can be the source of metal particles that end up in the white metal beaings and score the crank. As to how much work, depends... do you just want to get it healthy, other than the oil pressure were you happy with the engine before you took it out? If so, do the minimum, which should really include at least a bore hone and a set of Cords rings. In which case look critically at the pistons, the ring slots, no point putting new rings in worn pistons. And I suppose a new timing chain unless it's low mileage. And you know about getting the crud out of the back of the waterjacket.... ? There you see, mission creep already. If you weren't happy, do the lot, so long as the expenditure of all that ££ will make you happier or the engine perceptibly better. The urge to do stuff 'while I'm here' is what Stan (Foster461) calls Shipwrights Disease. Ivor Quote Link to post Share on other sites
EdMcC Posted March 16, 2010 Author Report Share Posted March 16, 2010 Ivor, Steve, Ade - thanks for your advice. Further investigation means more extensive work is unavoidable: pistons (the ones in her seem some type designed to cut oil consumption), liners, timing chain & tensioner also need replaced. Valves are ok. Are pistons/liners and bearings from Moss, Rimmer etc all from the same supplier? I only intend to do this job once and want to ensure I get decent quality bearings, pistons etc. Quote Link to post Share on other sites
EdMcC Posted March 26, 2010 Author Report Share Posted March 26, 2010 Ivor, Steve, Ade - thanks for your advice. Further investigation means more extensive work is unavoidable: pistons (the ones in her seem some type designed to cut oil consumption), liners, timing chain & tensioner also need replaced. Valves are ok. Are pistons/liners and bearings from Moss, Rimmer etc all from the same supplier? I only intend to do this job once and want to ensure I get decent quality bearings, pistons etc. The engine is going back together without hitch (am I tempting fate!). What about external oil feed kits...are they worth it and is the kit in place of or in addition to the original arrangements? Quote Link to post Share on other sites
stuart Posted March 26, 2010 Report Share Posted March 26, 2010 The engine is going back together without hitch (am I tempting fate!). What about external oil feed kits...are they worth it and is the kit in place of or in addition to the original arrangements? Dont use the external oil feed kit its not worth it and can lead to more problems than it is supposed to solve. Stuart Quote Link to post Share on other sites
Ade-TR4 Posted March 26, 2010 Report Share Posted March 26, 2010 Agreed! Don't use the external feed: It robs other parts of the engine (particularly the cam/ fuel pump/ distributor) of oil. A rebuilt engine should be spot on for oil-feed to all parts. Save the dosh! Adey Quote Link to post Share on other sites
Tony Millward Posted March 27, 2010 Report Share Posted March 27, 2010 (edited) Dont use the external oil feed kit its not worth it and can lead to more problems than it is supposed to solve. Stuart (moved question to TR6 forum) Edited March 27, 2010 by Tonymill Quote Link to post Share on other sites
EdMcC Posted April 3, 2010 Author Report Share Posted April 3, 2010 (edited) My TR4A engine is rebuilt, back in the car, and pretty much running line a dream - quiet and smooth - and I never thought i'd say that. The new pistons/liners and rear oil seal conversion are great jobs. The only niggle is getting the tickover sorted...it won't drop below 1050ish rpm. I think the throttle spindles on the Strombergs are dodgy and I'm having difficulty seeing them listed in the catalogues of the major suppliers. Any ideas where to source them? ps I scrapped the idea of the external oil feed. The new oil pump plus everything else done is giving excellent oil pressure. Edited April 3, 2010 by EdMcC Quote Link to post Share on other sites
stuart Posted April 3, 2010 Report Share Posted April 3, 2010 My TR4A engine is rebuilt, back in the car, and pretty much running line a dream - quiet and smooth - and I never thought i'd say that. The new pistons/liners and rear oil seal conversion are great jobs. The only niggle is getting the tickover sorted...it won't drop below 1050ish rpm. I think the throttle spindles on the Strombergs are dodgy and I'm having difficulty seeing them listed in the catalogues of the major suppliers. Any ideas where to source them? ps I scrapped the idea of the external oil feed. The new oil pump plus everything else done is giving excellent oil pressure. You could try Burlen Fuel Systems or Southern Carburettors. Stuart. Quote Link to post Share on other sites
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