400_racer Posted May 7, 2016 Report Share Posted May 7, 2016 Hi All, Hoping some of you knowledgable chaps might be able to help diagnose oil pressure issues on my poor brothers disco1 before he completely pulls all his hair out with it. He'd previously had problems with overheating and it boiling over, did several things but the last time it happened it did a good job and really cooked it, so decided to get a replacement engine. This new engine is now in and running but has no oil pressure once warm. A guage has been fitted which shows approx 25psi cold but soon drops as temps rise to show precisely 0psi at tickover, and registers a little higher when rev'd but still very low. This mirrors the oil light on the dash which comes on at tickover when warm but goes out when rev'd. So far he's checked/changed: - oil pickup is clear, and no cracks leaks in the pickup pipe and seal - oil is getting to the filter/filter housing and the turbo - turbo is new as the one from the old cooked engine was knackered - pressure release valve and spring replaced with new (old spring was about 20mm shorter than spec, though even the new one was a little short) - oil pump plates have been replaced with new and fitted to old engine cover and are now in spec (new engine cover and pump were well out of spec and showed signs of wear) - main and big end bearings replaced with new (shells on new engine were well worm) - oil cooler thermostat replaced with one from old engine (so not replaced with new but not sure if this system could affect pressures) Any other ideas on what we could try or where it could be loosing that much oil/pressure? Thinking maybe camshaft bearings? Does anyone know where the oil goes when it re-enters the engine via the filter housing? If the oil thermostat is stuck open and oil returns straight back to the sump then that could be contributary. Unfortunately the oil pathway diamgram shown in the manual doesnt include the cooler system We're probably missing something obvious (hopefully ) and you'll all be taking the pee if so just want him to get it fixed, but starting to think its just knackered Thanks in advance, Quote Link to comment Share on other sites More sharing options...
Saltings Posted May 7, 2016 Report Share Posted May 7, 2016 check the crank with a micrometer as it may have been ground in the past (wrong size shells bad oil pressure) have also seen brand new cranks already undersize or may need a regrind only a proper measure will tell either way Quote Link to comment Share on other sites More sharing options...
TONY R Posted May 7, 2016 Report Share Posted May 7, 2016 Saw a defender with just such a problem a few years ago , turned out to be camshaft bearings had moved some how lost oil pressure. Engine bloke who stripped it said it was pretty common on them. I woould look into this if i were you. Quote Link to comment Share on other sites More sharing options...
400_racer Posted May 7, 2016 Author Report Share Posted May 7, 2016 check the crank with a micrometer as it may have been ground in the past (wrong size shells bad oil pressure) have also seen brand new cranks already undersize or may need a regrind only a proper measure will tell either way Can the journals be measured with the crank in situ or does it need removing? I think he went with standard sized shells Saw a defender with just such a problem a few years ago , turned out to be camshaft bearings had moved some how lost oil pressure. Engine bloke who stripped it said it was pretty common on them. I woould look into this if i were you. Ah yes have read about this, the rear shell slides round or back and expose the oil way allowing free flow i think, however, everything i've read seemed to suggest it was a 200tdi problem not 300tdi? Not sure how the two engines differ in cam design but worth checking either way Quote Link to comment Share on other sites More sharing options...
Saltings Posted May 7, 2016 Report Share Posted May 7, 2016 big ends can be measured in situ with micromerer but not mains however you can get a kit which you put a strip of material under the shells and torque them down then remove and measure the compressed width of the material to determin wear etc https://www.youtube.com/watch?v=Q3Qm7vRoPKo this may help Quote Link to comment Share on other sites More sharing options...
Paul223 Posted May 8, 2016 Report Share Posted May 8, 2016 (edited) Unlikely to be big end or main bearing wear without you hearing it! Cam bearing do move on these, take the inspection plates off and check Still have the old engine? If so....remove oil pick up pipe, cut the sieve off and weld in an air line connector, turn compressor regulator down to 50 psi, fit modified pick up pipe to engine and plug air line in, it'll get a little messy and everything will leak a little but hopefully you'll find one big leak. Rocker cover off and inspection plates off will help Edited May 8, 2016 by Paul223 Quote Link to comment Share on other sites More sharing options...
rodp Posted May 8, 2016 Report Share Posted May 8, 2016 Saw a defender with just such a problem a few years ago , turned out to be camshaft bearings had moved some how lost oil pressure. Engine bloke who stripped it said it was pretty common on them. I woould look into this if i were you. This was a problem on some 200's, thought it was supposedly fixed on 300's but can happen on quite a few makes of engine. Causes exactly the problem you have. Quote Link to comment Share on other sites More sharing options...
Paul223 Posted May 8, 2016 Report Share Posted May 8, 2016 This was a problem on some 200's, thought it was supposedly fixed on 300's but can happen on quite a few makes of engine. Causes exactly the problem you have.When I've seen it usually the problem has been cam belt fail leading to bent push rods and an unseen cracked cam bearing, the bearing then takes some time work its way out, last one the push rod cup was damaged and checking all the push rods showed a few with slight bends, obviously whoever did the job just changed the badly bent rods, the bearing had broke up over time and was in the sump Quote Link to comment Share on other sites More sharing options...
rodp Posted May 8, 2016 Report Share Posted May 8, 2016 When I've seen it usually the problem has been cam belt fail leading to bent push rods and an unseen cracked cam bearing, the bearing then takes some time work its way out, last one the push rod cup was damaged and checking all the push rods showed a few with slight bends, obviously whoever did the job just changed the badly bent rods, the bearing had broke up over time and was in the sump On 200's it happened with no other problems. Not unknown on various makes of engine, not just LR. Must just be reverse blueprinting Quote Link to comment Share on other sites More sharing options...
walshie Posted May 8, 2016 Report Share Posted May 8, 2016 Does it have the right oil in it? Quote Link to comment Share on other sites More sharing options...
TONY R Posted May 8, 2016 Report Share Posted May 8, 2016 The defender had a 300 in it, one day he was coming back from The borders, had been pressing on a bit, and he stopped for juce near new castle some where, noticed the oil light was flickering, he rang me i told him to get it recovered here. He contacted the AA but his membership had lapsed a few months. And if he joined he would have to wait 24 hours before he could be recovered on a new membership. So he did try he Searched for a Discount got a oil pressure sensor fitted it on the road outside the shop, but no change. Told him to park up some place doss in the truck that night get recovered 10 am the next morning. DO NOT MOVE IT I SAID> About three hours latter he rings me .. Can you come with the A frame i am in Layburn near the chip shop engine as just gone bang i coasted in to a parking place. This was amasing Not so much that he made it from New castle but the fact he found a parking place near the chip shop . :lol: Engine ou it was history, had spun a big end shell crank was looking poorly, Took it for a check a nd grind, no way it was oval and scrap. Decided to strip the motor fully get it rebuilt.. Noticed the cam bearing and took the block to get it re bushed and line bored, but the bearing had spun pretty good and the block was out of spec and block was scrap. So i ended up Doing him a conversion i fitted a Daihatsu 2.8 DLturbo red top gear driven motor. Still running 12 years latter, but the Defenders Chassis is Rusted to dust now, and Aparently its in a shed on blocks running a milking machine now. :lol:. Quote Link to comment Share on other sites More sharing options...
armsid Posted May 9, 2016 Report Share Posted May 9, 2016 was the oil pessure valve seating properly? and as has been said earlier correct oil and filter Quote Link to comment Share on other sites More sharing options...
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