Iain T Posted October 8, 2020 Report Share Posted October 8, 2020 Heads off it's not a blocked oilway so as there is good oil pressure it can only be the cam? Suggestions please......quickly! Iain Link to comment Share on other sites More sharing options...
Iain T Posted October 8, 2020 Report Share Posted October 8, 2020 Engine builder spoke to Ken Newman, scroll and flat definitely in the cam so it must be a restriction in the block? Iain Link to comment Share on other sites More sharing options...
Sparky_Spit Posted October 8, 2020 Report Share Posted October 8, 2020 Ian, a quick check before you get to the stage of taking the head off, undo the 7/16th bolt (fitted with a copper washer) on the back nearside of the head. This bolt blanks the drilling hole that makes the oil path divert from the upwards drilling from the cam bearing and across through the head before meeting the upright drilling to the rear rocker pedestal. With that bolt removed and the engine running you can prove that the flow is okay or not at that point. That is the last point at which you can check for oil flow spurts with the engine running, as the next point "downstream" you can access is the hole in in the top of the head under the rocker pedestal, but obviously not when the engine is running. Link to comment Share on other sites More sharing options...
Sparky_Spit Posted October 8, 2020 Report Share Posted October 8, 2020 Just now, Sparky_Spit said: Ian, a quick check before you get to the stage of taking the head off, undo the 7/16th bolt (fitted with a copper washer) on the back nearside of the head. This bolt blanks the drilling hole that makes the oil path divert from the upwards drilling from the cam bearing and across through the head before meeting the upright drilling to the rear rocker pedestal. With that bolt removed and the engine running you can prove that the flow is okay or not at that point. That is the last point at which you can check for oil flow spurts with the engine running, as the next point "downstream" you can access is the hole in in the top of the head under the rocker pedestal, but obviously not when the engine is running. Just saw last posts above... too late! Link to comment Share on other sites More sharing options...
Iain T Posted October 8, 2020 Report Share Posted October 8, 2020 The engine builder is quick, he wants to find the problem! He has a couple more tests to do tomorrow before engine out time. Iain Link to comment Share on other sites More sharing options...
Nick Jones Posted October 8, 2020 Report Share Posted October 8, 2020 You do know that there isn’t meant to be much oil flow to the rocker gear don’t you? The other irony is that when your rockers and rocker shaft are good, even less oil is visible as the close tolerances limit the flow at the exit points. Nick Link to comment Share on other sites More sharing options...
Iain T Posted October 8, 2020 Report Share Posted October 8, 2020 Nick, yes I am aware and my new bushed rocker arms are probably of closer tolerance than original. Do you think I'm being too paranoid? Iain Link to comment Share on other sites More sharing options...
daverclasper Posted October 8, 2020 Author Report Share Posted October 8, 2020 (edited) 48 minutes ago, Nick Jones said: The other irony is that when your rockers and rocker shaft are good, even less oil is visible as the close tolerances limit the flow at the exit points. Oh dear, hope I'm not overcomplicating this. I had a different result to that Nick. Noticed that less/no oil visible coming out of top of about the 6 front rockers. Stripped down shaft. Rocker holes and shaft/holes clean (as I thought they may be blocked). Very worn shaft at front half, in the area/plane (lower to rear, along the length), where I assume the rockers are under spring tension, which as I remember is also the area of shaft than has the oil scrolls/grooves. The scrolls were non/partially existent. Assumed that was limiting/stopping oil supply. New shaft and was ok, good dribbling out of the top of all rockers at idle (though I did notice that one rocker, about halfway along, wasn't very recently?, when checking valve clearance) . Any ideas please?. Someone else?, Maybe Gully?, can't remember, had same issue and cure a while back I think. Dave Edited October 8, 2020 by daverclasper Link to comment Share on other sites More sharing options...
Sparky_Spit Posted October 9, 2020 Report Share Posted October 9, 2020 Iain - If there is definitely no oil getting into the rocker shaft and you have a cam with the correct oil-squirt-flat on the rear journal, then maybe you have the rear cam bearing fitted with the oil hole misaligned? Or the bearing has slipped round from its fitted position. That's assuming you have bearings fitted of course. Fingers crossed it's something simple. Link to comment Share on other sites More sharing options...
Iain T Posted October 9, 2020 Report Share Posted October 9, 2020 There isn't a cam bearing in my engine. I think for most 2 litre 6 pots cam bearings were never fitted from the factory. It would have been something to check but I await today's report! As it's supposed to be peeing down this afternoon I might pop down to the engine guy. It can now only be restricted block oilway? The pump has good pressure so probably not the main suspect. Iain Link to comment Share on other sites More sharing options...
Mark B Posted October 9, 2020 Report Share Posted October 9, 2020 As I mentioned earlier, there was no oil reaching my rockers on first start up with a recon head fitted. The oil gallery that feeds the rear pedestal was blocked. Not obviously apparent, the hole looked clear and could poke a piece of mig wire into the hole for about 15mm. I thought I was hitting the bottom of the gallery until I poked the same piece of wire into a spare head and it went in a lot further. Realising there was a blockage I used more force on the Mig wire and gradually broke through. You can access the same gallery through the small bolt right rear of the head. The blockage looked like hardened compressed oil. Rockers, shaft and pedestal was blown through with cleaner and compressed air. Link to comment Share on other sites More sharing options...
Iain T Posted October 9, 2020 Report Share Posted October 9, 2020 Mark, exactly one reason I want to go and visit the engine guy. He has specialised in heads for 40 years so I assume he has many widgets to clear oilways etc. I did try poking with some MiG wire but it was 1mm diameter so not flexible enough. Iain Link to comment Share on other sites More sharing options...
Iain T Posted October 9, 2020 Report Share Posted October 9, 2020 It's engine out time! Engine guy said it's the only way to find the problem. I just hope it's not a very worn cam rear journal because that's terminal for the block other than line boring and fitting cam bearings.... I still have my fingers crossed for crud in the block🤞 Iain Link to comment Share on other sites More sharing options...
Gully Posted October 11, 2020 Report Share Posted October 11, 2020 On 08/10/2020 at 18:13, daverclasper said: Oh dear, hope I'm not overcomplicating this. I had a different result to that Nick. Noticed that less/no oil visible coming out of top of about the 6 front rockers. Stripped down shaft. Rocker holes and shaft/holes clean (as I thought they may be blocked). Very worn shaft at front half, in the area/plane (lower to rear, along the length), where I assume the rockers are under spring tension, which as I remember is also the area of shaft than has the oil scrolls/grooves. The scrolls were non/partially existent. Assumed that was limiting/stopping oil supply. New shaft and was ok, good dribbling out of the top of all rockers at idle (though I did notice that one rocker, about halfway along, wasn't very recently?, when checking valve clearance) . Any ideas please?. Someone else?, Maybe Gully?, can't remember, had same issue and cure a while back I think. Dave The dry rocker issue I had was a while ago and led me replacing the rocker shaft (kept all bar a couple of the original rockers). The original shaft was very worn in places and heavily grooved by the dry rocker. The lack of oil to that one was simply down to some muck in that particular feed hole in the shaft; all the others were okay, but given the wear state of the shaft I put a new one on. It seemed to have been an issue for a while, as the previous owner appeared to have put copper slip in the pushrod/rocker adjuster ball and socket joint. It was that pushrod that I found recently to be 'capturing' the adjuster on the rocker until I took some material off the adjuster ball. Gully Link to comment Share on other sites More sharing options...
Iain T Posted October 13, 2020 Report Share Posted October 13, 2020 Engine is stripped, again! Big ends on 5 and 6 buggered so definitely oil starvation. Everything else measures ok including the cam journals. Cam is as it should be with scrolls and flat. CCTV showed no oil way obstructions. The oil pump and/or pressure relief must be unserviceable. Weird as the disassembled pump looks good with little marking on the cap or body??? New parts ordered and will be fitted tomorrow then on the bench the engine will be turned over and the pressure measured. Apparently when checked previously the pressure went up to 65psi then dropped off. What bugs me is the oil warning light never came on! I can only put it down to yet another Jigsaw gremlin come back to bite me even though the engine and pump had only done about 5k miles prior to me having it rebuilt..... As partial relief of my paranoia I was going to fit an oil pressure gauge anyway. Just as well I felt as though something was harsh and wrong in a few more miles the engine could have seized with possible devastating results for the car and me!!! Hopefully all goes well tomorrow🤞 Iain 1 Link to comment Share on other sites More sharing options...
daverclasper Posted October 13, 2020 Author Report Share Posted October 13, 2020 (edited) Could have been worse like you said Iain. Good luck with it. I think the oil light only comes on at pretty low oil pressure anyway?, so not a great guide to health, I guess?. Oil press gauges, sometimes called worry gauges, though some worry may have helped in this situ. Dave Edited October 13, 2020 by daverclasper Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 13, 2020 Report Share Posted October 13, 2020 low pressure warning is around 8psi Link to comment Share on other sites More sharing options...
Iain T Posted October 13, 2020 Report Share Posted October 13, 2020 3 minutes ago, Pete Lewis said: low pressure warning is around 8psi By that time on a motorway blast you're f*****! What is the point of a warning light set that low? Barmy. 17 minutes ago, daverclasper said: Oil press gauges, sometimes called worry gauges, though some worry may have helped in this situ. Good information is king! Will someone please tell the government.......sorry I digress. I'll report back ASAP. Iain Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 13, 2020 Report Share Posted October 13, 2020 its set low so it wont get you worried by coming on Ha ! whats that awful racket !!!! Pete Link to comment Share on other sites More sharing options...
Iain T Posted October 13, 2020 Report Share Posted October 13, 2020 13 minutes ago, Pete Lewis said: whats that awful racket !!!! It's called pre-detonation🌋 Link to comment Share on other sites More sharing options...
SpitFire6 Posted October 13, 2020 Report Share Posted October 13, 2020 It is an oil change light😀. Has worked for me in the very very long distant past. An 8 PSI could be changed to 20. Satisfying if it never illuminates even when lugging the engine. Tell-tale light or gauge has never stopped an engine blowing that I was driving. Once the oil pressure starts dropping you are already on borrowed time. Hail STP. Majority of my blown engines are pinked to death. Lambda should be wired to oil pressure light. LOL. Link to comment Share on other sites More sharing options...
Nick Jones Posted October 13, 2020 Report Share Posted October 13, 2020 2 hours ago, Iain T said: Engine is stripped, again! Big ends on 5 and 6 buggered so definitely oil starvation. Everything else measures ok including the cam journals. Cam is as it should be with scrolls and flat. CCTV showed no oil way obstructions. The oil pump and/or pressure relief must be unserviceable. Weird as the disassembled pump looks good with little marking on the cap or body??? New parts ordered and will be fitted tomorrow then on the bench the engine will be turned over and the pressure measured. Apparently when checked previously the pressure went up to 65psi then dropped off. What bugs me is the oil warning light never came on! I can only put it down to yet another Jigsaw gremlin come back to bite me even though the engine and pump had only done about 5k miles prior to me having it rebuilt..... As partial relief of my paranoia I was going to fit an oil pressure gauge anyway. Just as well I felt as though something was harsh and wrong in a few more miles the engine could have seized with possible devastating results for the car and me!!! Hopefully all goes well tomorrow🤞 Iain Strange. 5 and 6 are fed from different main bearings and both of those are early in the feed path. I have heard of others having problems with no.5 but we never really got to the bottom of why. It was a competition car and surge was one suspect. The other was that the oil was not hot enough (hillclimber). Are the crank journals ok? Be aware that quality control on the new pumps is patchy. They need careful measuring before installing and sometimes some of the casting flash removed from the internal passages. Hope all goes well tomorrow Nick Link to comment Share on other sites More sharing options...
Iain T Posted October 13, 2020 Report Share Posted October 13, 2020 Nick, the crank has been reground today I'll ask about the mains. I had a long conversation with the guy about dodgy pumps but he reckons the ones he buys are fine! However I will be making sure everything is checked. Iain Link to comment Share on other sites More sharing options...
Iain T Posted October 14, 2020 Report Share Posted October 14, 2020 14 hours ago, Nick Jones said: Strange. 5 and 6 are fed from different main bearings and both of those are early in the feed path. I have heard of others having problems with no.5 but we never really got to the bottom of why. It was a competition car and surge was one suspect. The other was that the oil was not hot enough (hillclimber). Are the crank journals ok? Nick, sorry my 5 and 6 is your 1 and 2 so perhaps this explains it? I saw the bock yesterday, it's completely stripped and they said they have checked all the oilways. The engine guy now regrets not putting a new oil pump in........I didn't tell him not to! A rooky mistake for such an experienced company. The supplier of the new pump is apparently, allegedly, hopefully fine as he has put them in several racing and fast road Triumphs. Iain Link to comment Share on other sites More sharing options...
Nick Jones Posted October 14, 2020 Report Share Posted October 14, 2020 1 & 2 are the front two cylinders and furthest from the pump in circulation terms. All pumps should be measured before fitting. New might mean unused, sadly does not guarantee fitness for purpose. Measuring is quick and easy and involves only feeler gauges and a steel rule. Excessive gear end float can be corrected by lapping the housing. Excessive clearance between gears means bin food. Nick Link to comment Share on other sites More sharing options...
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