miketomcat Posted April 26, 2022 Author Share Posted April 26, 2022 I'm sure I can sort something. Mike 1 Quote Link to comment Share on other sites More sharing options...
Nonimouse Posted April 26, 2022 Share Posted April 26, 2022 16 minutes ago, miketomcat said: I'm sure I can sort something. Mike Last of the true romantics Quote Link to comment Share on other sites More sharing options...
Wytze Posted April 26, 2022 Share Posted April 26, 2022 Touch wood, this will be end of men touching men's wood.. in this topic🙈 I do like the gear knob's though 1 1 Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 29, 2022 Author Share Posted June 29, 2022 Can you guess what job I need to do soon, special tool made. Mike Quote Link to comment Share on other sites More sharing options...
Nonimouse Posted June 29, 2022 Share Posted June 29, 2022 Gear knob removal tool 1 Quote Link to comment Share on other sites More sharing options...
Stellaghost Posted June 29, 2022 Share Posted June 29, 2022 Some sort of locking tool ? Regards Stephen Quote Link to comment Share on other sites More sharing options...
TSD Posted June 29, 2022 Share Posted June 29, 2022 I think I know, for two reasons. One, I think you might have mentioned it recently, and two, I have a very similar looking tool in my workshop. Except I didn't need to replace mine, I just forgot to fit them at build Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 29, 2022 Author Share Posted June 29, 2022 2 minutes ago, TSD said: I think I know, for two reasons. One, I think you might have mentioned it recently, and two, I have a very similar looking tool in my workshop. Except I didn't need to replace mine, I just forgot to fit them at build Correct, valve stem seals. She's getting a bit smokey on overrun. Mike Quote Link to comment Share on other sites More sharing options...
TSD Posted June 29, 2022 Share Posted June 29, 2022 I always sort of assumed that wouldn't be the case on a diesel, since there's no intake vacuum to draw oil down the guides. But no practical experience either way, so Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 29, 2022 Author Share Posted June 29, 2022 Well I certainly hope it helps because my mot man is going to be grumpy if I don't do something. Mike Quote Link to comment Share on other sites More sharing options...
steve b Posted June 29, 2022 Share Posted June 29, 2022 45 minutes ago, TSD said: I always sort of assumed that wouldn't be the case on a diesel, since there's no intake vacuum to draw oil down the guides. But no practical experience either way, so Yes , there is on over run with no throttle . Not as much as a petrol but it's there . Steve Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 29, 2022 Author Share Posted June 29, 2022 To be honest I wouldn't be surprised if the seals are so knackered that no vacuum is required. Mike Quote Link to comment Share on other sites More sharing options...
TSD Posted June 29, 2022 Share Posted June 29, 2022 Oh I agree there is *some* vacuum, (by definition, otherwise no air would flow in!) but I was only thinking out loud that it if it were enough to cause smoke only on the overrun because of poor seals, then the rest of the time you'd have 15psi+ blowing the other way into the rocker box, which would put a lot of oil mist into the separator and then into the air intake pipework, and a noticeably 'oily' engine. Even with the big turbo on the TGV engine, I never noticed any vacuum indicated on the boost gauge - one of the VDO ones for petrol engines, scaled in PSI on the boost side, and mbar on the vacuum side. Actually it does now indicate a little vacuum all the time, but that's because the boost spikes bent the needle smacking the end stop at 25psi I'm not sure what other mechanisms there are for overrun oil smoke (rings? turbo oil seals?), so I'm interested to see how much difference it makes. Hopefully Mikes right, especially as my shed is full of Ibexes at the moment, would have to do a bit of shuffling to get another one in there! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 29, 2022 Share Posted June 29, 2022 Quite possibly more that at idle the exhaust isn't hot enough to burn oil as it drips down into the manifold, rev it up and the heat is there to make it smoke... Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 29, 2022 Author Share Posted June 29, 2022 Oil mist in the intake you say ....... Yeah about that. Mike 1 2 Quote Link to comment Share on other sites More sharing options...
TSD Posted June 29, 2022 Share Posted June 29, 2022 'Like' seems somehow the wrong button to press for this post, but you know what I mean Quote Link to comment Share on other sites More sharing options...
cackshifter Posted July 4, 2022 Share Posted July 4, 2022 The stem seals tend to blow off the top of guides, I seem to recall a thread about the right sort of threadlock to use to hold them on. I guess if the stem-guide clearance is anything but tiny there is pressure on them to lift off. 1 Quote Link to comment Share on other sites More sharing options...
Peaklander Posted July 5, 2022 Share Posted July 5, 2022 22 hours ago, cackshifter said: I seem to recall a thread about the right sort of threadlock to use to hold them on. What a good memory recall. It was one of my threads and this link should go direct to page 2 where there is reference to Bondloc b638-50 Quote Link to comment Share on other sites More sharing options...
miketomcat Posted July 12, 2022 Author Share Posted July 12, 2022 So the plan was to do the stem seals at the weekend...... Somewhere along the line last week I managed to catch covid que a rubbish weekend especially when everyone else went down with it as well. After several days of TV, the upside is I'm feeling better and my 5 days doesn't run out till Wednesday evening. I stripped the rocker shaft off found tdc and set to it the tool copied from here is fantastic. Valves 1,2 and 7,8 all done however the old seals all but fell off, really quite lose. Spin crank 180° ready to do piston 2 and 3, except it won't. It goes solid, try the other way....the same. after a couple of trys it goes over. Valves 3,5,6 again no problem, this time the seals had to be pulled off. Valve 4 has no seal at all, that'll explain the smoke then....I hope. I think it wouldn't turn over due to hydraulic lock caused by the lack of stem seal on valve no 4, but once back together it turns over fine. Starts and runs fine but I can't take it for a run yet. Mike 1 Quote Link to comment Share on other sites More sharing options...
TSD Posted July 12, 2022 Share Posted July 12, 2022 10 minutes ago, miketomcat said: I think it wouldn't turn over due to hydraulic lock caused by the lack of stem seal on valve no 4, but once back together it turns over fine. Don't think it can be anything other than compression, there's only 8 things that can get in the way, and you can see them all from there The only other cause, as I've told you before, is that engine is cursed - it does nothing except produce loads of power, a bit of smoke and occasional nasty surprises Quote Link to comment Share on other sites More sharing options...
miketomcat Posted July 12, 2022 Author Share Posted July 12, 2022 32 minutes ago, TSD said: Don't think it can be anything other than compression, there's only 8 things that can get in the way, and you can see them all from there The only other cause, as I've told you before, is that engine is cursed - it does nothing except produce loads of power, a bit of smoke and occasional nasty surprises I blame the bloke who built it up out of a broken engine and a pile of bits......no wait hang on a minute. Mike 1 2 Quote Link to comment Share on other sites More sharing options...
Maverik Posted July 13, 2022 Share Posted July 13, 2022 If you think about it you should get very little oil leak from the missing valve seal - as the manifolds the valves run through are always positive pressure so you in theory should have more issue of pressure leakage into the rocker space. Quote Link to comment Share on other sites More sharing options...
miketomcat Posted July 13, 2022 Author Share Posted July 13, 2022 Technically the inlet has vacuum as the piston drops until the turbo spools up so theoretically it could draw oil down at and just after start up. Similarly when you shut down any oil on the valve stem and spring cap can run straight down and pool in the ports. It is entirely possible the rings are tired especially as we think a couple were stuck when this engine went in. Obviously if your going to test drive nailing 1.5ton of box trailer on the back is the correct thing to do. so anyway it did smoke a bit initially but seems to of cleared and looks to be better than it was, I guess only time will tell. Mike 1 1 Quote Link to comment Share on other sites More sharing options...
Maverik Posted July 16, 2022 Share Posted July 16, 2022 On 7/13/2022 at 2:17 PM, miketomcat said: Technically the inlet has vacuum as the piston drops until the turbo spools up so theoretically it could draw oil down at and just after start up. Similarly when you shut down any oil on the valve stem and spring cap can run straight down and pool in the ports. It is entirely possible the rings are tired especially as we think a couple were stuck when this engine went in. Obviously if your going to test drive nailing 1.5ton of box trailer on the back is the correct thing to do. so anyway it did smoke a bit initially but seems to of cleared and looks to be better than it was, I guess only time will tell. Mike Hmm interesting - during the normal aspiration combustion due to low engine speed, I'd not thought about that. 👍 Quote Link to comment Share on other sites More sharing options...
cackshifter Posted July 16, 2022 Share Posted July 16, 2022 And at start up the vacuum pump is busy building vacuum, exhausting the air into the crankcase, and so maybe even pressurising it for a moment. Not the greatest idea, maybe the cheapest to make. Quote Link to comment Share on other sites More sharing options...
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