PatK Posted October 16 Report Share Posted October 16 Hi all, I'm starting work again on the Vitesse this winter and yesterday thought that I would check the cylinder compressions on Nr. 1 to 6. The engine does not seem to burn oil, but the exhaust fumes definitely smell of burnt oil and the plugs soot up easily. The test was done cold with the plugs out but I've just remembered that I did not open the throttle fully and I guess that this would make a difference? These are the pressures, 1. 135 psi, 2. 140psi, 3. 140psi, 4. 135psi. 5140 psi. 6. 135psi. Is this OK, the engine runs fine or perhaps the smell of oil in the exhaust is valve guide wear ? Thanks everyone. Patrick Link to comment Share on other sites More sharing options...
Iain T Posted October 16 Report Share Posted October 16 You need to test again with WOT but those numbers look nice and even. Are the plugs wet with oil or is it just running rich? Iain Link to comment Share on other sites More sharing options...
johny Posted October 16 Report Share Posted October 16 A puff of smoke from exhaust when opening throttle after trailing down an incline would indicate valve guide oil.... Whats the mileage on engine and its rebuild status? Has it got a rocker oil feed? Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 16 Report Share Posted October 16 just to check this doesnt have the dreaded external rocker oil feed fitted?? ( Ha Snap ) dont overfill the dashpots and is this on strombergs , had feeling it had SUs weaken off is the simpest move rich running washes the bores too much that can make things oily Pete Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 1 hour ago, Iain T said: You need to test again with WOT but those numbers look nice and even. Are the plugs wet with oil or is it just running rich? Iain Thanks Ian, no the plugs are not wet just get sooty quickly.I will do the test again and see how much it increases. I guess any reading around 150 psi is good? Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 16 Report Share Posted October 16 yes thats some fair results on a cold engine as all quite close no wild variations , do check the breather in the rocker cover there should be a gauze held unde rsome cheap tinwork take it out and wash in petrol you wont know if its blocked until you find it Pete Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 11 minutes ago, Pete Lewis said: just to check this doesnt have the dreaded external rocker oil feed fitted?? ( Ha Snap ) dont overfill the dashpots and is this on strombergs , had feeling it had SUs weaken off is the simpest move rich running washes the bores too much that can make things oily Pete No Pete I have removed the dreaded fitting on your advice and also fitted Strombergs, I did notice that the oil level in the Strombergs seems to slowly go down, perhaps this is the problem? I will weaken off the mixture and see if that makes a difference. Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 16 Report Share Posted October 16 are the stroms top adjuster or jet underneath ?? Pete Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 18 minutes ago, johny said: A puff of smoke from exhaust when opening throttle after trailing down an incline would indicate valve guide oil.... Whats the mileage on engine and its rebuild status? Has it got a rocker oil feed? Hi Johny, sadly I don't know the true mileage, and yes it could be valve guide wear. The cylinder head looks like it was overhauled some time ago, having a non standard paint finish and I suspect it had been modded possibly with non standard camshaft and the fitment of over large SU carbs, which have now gone thankfully. If I get time this winter I will take the head off and overhaul it. Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 7 minutes ago, Pete Lewis said: yes thats some fair results on a cold engine as all quite close no wild variations , do check the breather in the rocker cover there should be a gauze held unde rsome cheap tinwork take it out and wash in petrol you wont know if its blocked until you find it Pete Yes Pete I will do that although I did it not too long ago, but I will check again. As a matter of interest Pete, can you drop the sump with the engine in situ.? I have a scissors lift and can get under it no problem. Link to comment Share on other sites More sharing options...
johny Posted October 16 Report Share Posted October 16 To answer that one, yes the sump can be removed for bearing and oil pump inspection and is well worth doing. However you need to undo the engine mounts to be able to jack it up quite a bit so the sump can drop down to clear the oil pump intake (remember this goes to almost the bottom of the sump) and can then be slid back over the rack and out. I did it without undoing the exhaust but the difficulty, especially if the car is up in the air, is where and with what to jack the engine - a hoist would probably be best but I jacked the engine and inserted wood blocks between mounting brackets and chassis to keep it securely raised... Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 16 Report Share Posted October 16 yes the sump is a bit of a fiddle the oil pump gets in the way or easy removal you can faf around and it just drops off when you dont know why on the vit6 it had a gauze splash screen that got in the way in fact i undid the oil pump bolts through the gap and dropped the pump it went back without the gauze who needs strainer anyway Hmm yes lift the engine a fair bit to allow clear air between rack and sump just watch the hoses etc. its a lot easier on the big saloon Ha! Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 1 hour ago, johny said: To answer that one, yes the sump can be removed for bearing and oil pump inspection and is well worth doing. However you need to undo the engine mounts to be able to jack it up quite a bit so the sump can drop down to clear the oil pump intake (remember this goes to almost the bottom of the sump) and can then be slid back over the rack and out. I did it without undoing the exhaust but the difficulty, especially if the car is up in the air, is where and with what to jack the engine - a hoist would probably be best but I jacked the engine and inserted wood blocks between mounting brackets and chassis to keep it securely raised... Thanks Johny, thats good information, hopefully I may do that this winter, I assume that you can also access the crankshaft thrust washers here also, but I have yet to check the end float. Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 1 hour ago, Pete Lewis said: yes the sump is a bit of a fiddle the oil pump gets in the way or easy removal you can faf around and it just drops off when you dont know why on the vit6 it had a gauze splash screen that got in the way in fact i undid the oil pump bolts through the gap and dropped the pump it went back without the gauze who needs strainer anyway Hmm yes lift the engine a fair bit to allow clear air between rack and sump just watch the hoses etc. its a lot easier on the big saloon Ha! Thanks Pete, I'm quite good at faffing around and time wasting! Link to comment Share on other sites More sharing options...
johny Posted October 16 Report Share Posted October 16 Yes all accessible but front main bearing needs bridge piece removing so if others look ok probably best to leave alone. Difficult to get it to seal again without removing engine front plate. Other problem is maintaining cleanliness... Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 16 Report Share Posted October 16 (edited) so why do you fancy getting oily then ??? is there a crank problem and something to order is Canley do a THICK sump gasket its worth getting one far better than the usual paper type Pete Edited October 16 by Pete Lewis Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 Oily is my middle name Pete! Actually thats why I was seeking information on the cylinder pressures because if the opinion was that they were all too low, then i thought that I would get the pistons out, re ring them and at the same time fit new big end and main bearings also plus a glaze bust. If my Jag Mk2 sells at auction tomorrow then I will have lots of room to work on the Vitesse and the money to do it with, but it probably won't sell as classic car prices have dropped off a cliff lately as we all wait for the budget, nobody wants to spend money. Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 4 hours ago, Pete Lewis said: are the stroms top adjuster or jet underneath ?? Pete They are jets underneath Pete Link to comment Share on other sites More sharing options...
johny Posted October 16 Report Share Posted October 16 Although your readings look pretty good you could also have done a wet test to compare how much difference a capful of oil in each bore makes. Obviously got to be the same instrument and then negates any error in it.... Link to comment Share on other sites More sharing options...
daverclasper Posted October 16 Report Share Posted October 16 6 hours ago, PatK said: Thanks Ian, no the plugs are not wet just get sooty quickly Hi Pat. Maybe to bear this in mind?, that my Vitesse in slow running/idling, the plugs are quite sooty. general running, brownish. Cruising on Motorways at 2,500 rpm (overdrive and 3.27 diff), plugs are a pale grey. Other folk have noticed differences in plug colour, with different driving conditions. Maybe not typical, or how it should be? Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 Thanks Dave, that makes good sense, as after a couple of good runs this summer when it wasn't raining, I checked the plugs and they were light grey. Link to comment Share on other sites More sharing options...
PatK Posted October 16 Author Report Share Posted October 16 1 hour ago, johny said: Although your readings look pretty good you could also have done a wet test to compare how much difference a capful of oil in each bore makes. Obviously got to be the same instrument and then negates any error in it.... Thanks Johny, I will do that later on when I start the complete overhaul of the car and engine, but only if the Jag sells. Link to comment Share on other sites More sharing options...
johny Posted October 16 Report Share Posted October 16 well if the oil makes no difference theres not much engine overhaul needed as both rings and valves good so its just a case of investigating possible worn valve guides? Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 16 Report Share Posted October 16 and dont overfill the dashpots i asked as top adjustables can leak out damper oil , bottom adjusters dont have this problem advise you dont use plugs with an R in the suffix and at 50 yr old whats the problem with a bit of oil burn , if you dont expect utopia Pete Link to comment Share on other sites More sharing options...
PatK Posted October 17 Author Report Share Posted October 17 11 hours ago, Pete Lewis said: and dont overfill the dashpots i asked as top adjustables can leak out damper oil , bottom adjusters dont have this problem advise you dont use plugs with an R in the suffix and at 50 yr old whats the problem with a bit of oil burn , if you dont expect utopia Pete Ah Pete I wish I had a bottom adjuster, but at 83 years old its a bit too late!! Link to comment Share on other sites More sharing options...
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