glang Posted August 30, 2019 Share Posted August 30, 2019 I had the same problem with the sealing block front bolt thread and rather than take off the sump again I drilled and tapped it to suit an M10 allen cap head bolt. Its a bit fiddly as the front crank pulley had to come off but quite effective.... With the coolant loss its also possible to come from a hose connection or even a core plug as under pressure it can leak as vapour and so be difficult to detect. Its worth checking hose tightness and inspecting all core plugs (unfortunately not all of these are accessible). Quote Link to comment Share on other sites More sharing options...
daver clasper Posted August 31, 2019 Share Posted August 31, 2019 I think this noise was discounted as pinking in a previous thread?. I used to have pinking in the Vitesse at mid/higher revs when accelerating, though non at the usual low revs and high gear/load. I think the car is set up better now and no longer does it. just a thought. Dave Quote Link to comment Share on other sites More sharing options...
glang Posted August 31, 2019 Share Posted August 31, 2019 I think it does it when revved stationary as well which should discount pinking shouldnt it? Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 1, 2019 Author Share Posted September 1, 2019 If it is a high Speed pinking then presumably, this can be corrected by a pre-programmed Distributor? I have tried retarding the Basic ingnition which has only marginal effect but the idle is very uneven as a result. Alternativly I can advance the ignition at idle and the engine ticks over much faster and evenly. But when I do the "pinking" is no better, perhaps worse Quote Link to comment Share on other sites More sharing options...
glang Posted September 1, 2019 Share Posted September 1, 2019 The most likely causes of pinking are: weak mixture, low octane fuel and incorrect ignition timing (including faulty operation of the distributor advance/retard system). It will be worse in an engine that runs hot but in my case reducing the amount of air leaking in around the carburettor spindles made the biggest improvement.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 2, 2019 Author Share Posted September 2, 2019 If only I could be sure that this is actually the case. Certainly the mixture set at the carb using colortune was correct but I made it a bit richer anyway. I use 98 octane fuel. Is the Distributor faulty? I do not have the Impression that power is lacking in any way. I am inclined to think there is a mechanical Problem somewhere - a worn or weak tappet spring for example. Perhaps listening with a stethoscope might Isolate the root cause.... Quote Link to comment Share on other sites More sharing options...
glang Posted September 2, 2019 Share Posted September 2, 2019 Its fairly easy to test the two functions of the distributor: The advance mechanism (operated by weights inside that fly out under centrifugal force) is working if, when using a strobe to set the timing, you can see the pulley mark move to more degrees before top dead centre as you rev the engine. Retard (not all engines use this but I assume yours does) is tested by sucking on its vacuum pipe then with the distributor cap off you should see its top plate with points or electronic ignition sensor rotate easily. Of course this doesnt prove that the amount of change in each case is correct (the manual specifies the correct degrees of movement) but if they work its unlikely the distributor is the cause of the problem.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 2, 2019 Author Share Posted September 2, 2019 Yes I have done this test of the vacuum function and the top plate with Points does move .....but not very much. I am not sure if it easily moves as it Needs a lot of lung power. I then tried to move the finger ( I have one of the new better red ones) to check the function of the weights and it hardly moves at all. It seems that this is correct and expected. Quote Link to comment Share on other sites More sharing options...
glang Posted September 3, 2019 Share Posted September 3, 2019 yes thinking about it both of these mechanisms advance the timing so if they dont work (weights stuck, vacuum pipe disconnected etc) the engine will not run as well as it should but it wont produce pinking. One test I do for testing that pinking isnt due to weak mixture is to pull the choke out slightly while the engine is making the noise. If theres an improvement its an indication of where to investigate further.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 3, 2019 Author Share Posted September 3, 2019 Yes you have mentioned that before and I did try it last year, no difference to the Sound. I have been told off for calling it pinking, which only occurs at low engine revs when trying to accelerate - the same Sound as a diesel engine if you are in too low a gear. I cannot get my Herald to pink like that. Oh I forgót to mention that I found the bottom hose weeping at the Joint which I have now tightened up. This has solved the water loss. I am away for some days now but when I get back I will try to listen to the rattle with the bonnet open. It seems to be there but not so loud at a fast idle so perhaps I can, with some help, hear if it is coming from the bottom or the top or the front or the back of the engine.......plenty of choices! Quote Link to comment Share on other sites More sharing options...
RobPearce Posted September 3, 2019 Share Posted September 3, 2019 I'm not sure whether the forum will let you but if you can attach a sound recording / video then somebody might recognise the noise. Quote Link to comment Share on other sites More sharing options...
glang Posted September 3, 2019 Share Posted September 3, 2019 I just cant think of anything else that could generate a sound that the mechanic would diagnose as a crank bearing problem..... Must admit Ive never heard the noise produced by conrod small end or camshaft bearing wear so could it be one of those? Quote Link to comment Share on other sites More sharing options...
thescrapman Posted September 4, 2019 Share Posted September 4, 2019 2 other things that can cause a knocking noise is a lose crank pulley and the distributor drive cog moving up and down as the endfloat is wrong. I have had both, and the drive cog make a very loud noise Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 4, 2019 Author Share Posted September 4, 2019 Now that is a good thought! Both of those items I have removed and replaced. i have been given a Special stethascope to try and localise the noise. Will Report back in a week when I get home again Quote Link to comment Share on other sites More sharing options...
RobPearce Posted September 4, 2019 Share Posted September 4, 2019 Indeed, good thought Colin. Both of those are also low down on the block, where a mechanic might mistake them for crank bearing noises. Quote Link to comment Share on other sites More sharing options...
daver clasper Posted September 10, 2019 Share Posted September 10, 2019 Just a thought, if it may be pinking. Would weak advance springs cause too much advance at the wrong time?. Dave Quote Link to comment Share on other sites More sharing options...
glang Posted September 10, 2019 Share Posted September 10, 2019 Think it does it all the time Dave so that should discount pinking.... Quote Link to comment Share on other sites More sharing options...
daver clasper Posted September 10, 2019 Share Posted September 10, 2019 Ok Glang. Thought I read way back on thread it was noisy, accelerating from 60 to 70. Quote Link to comment Share on other sites More sharing options...
glang Posted September 10, 2019 Share Posted September 10, 2019 Quoted from Antonnick- It seems to be there but not so loud at a fast idle so perhaps I can, with some help, hear if it is coming from the bottom or the top or the front or the back of the engine.......plenty of choices! Youre right Dave but also as above.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 20, 2019 Author Share Posted September 20, 2019 The use of the stethoscope did not give any clues. Perhaps this is to be expected as the rattle/clang onlx occurs under load at 2.500 to 3000 revs approx. I have though ordered some gaskets for the distrubutor pedestal which have not arrived yet. But I have removed the Distributor in order to measure the gear float. This seemed like an easy Thing to do...but it is not. The Manual says to remove the drive gear, put in a washer temporarily over the geardrive shaft and then put the drive gear back in. Thence the Distributor is placed back on to the pedestal. The gap between the pedestal flange and the Distributor flange measured. I found you Need to replace the nuts and schrew them dowm finger tight in order to stop the flange rocking. The Manual has incorrectly stated the Maximum tolerance in mm as 1,78. It should be 0,178 mm in converting the imperial measurement of 0,007 in. Now the washer I used measures 1,49 mm thickness and after a lot of playing about using feeler gauges, I measured the gap as 1,35, perhaps 1,40mm if you try and push the feelers in with pressure. It is a bit awkward to measure as there is not much room and I get the Feeling that the gap varies depending on where you measure. Oh I forgot, any gasket that was there before had broken up. It was very thin. OK , so if the end float difference as measured is now 0,09mm, then I Need a gasket of 0,03 for the correct mean tolerance to bring it to 0,12mm . If , on the other Hand the 1,35 is valid, then I do not Need any gasket, which is in effect what I have now. But then I thought, what happens when the temporary washer is removed? The measured tolerance is then fudge, so perhaps the washer is permanent? Confused 😟 Quote Link to comment Share on other sites More sharing options...
RobPearce Posted September 20, 2019 Share Posted September 20, 2019 No, the washer is only there to give you a gap if the actual clearance is already positive (and hence your required gasket is less than 0.007" thick). Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 21, 2019 Author Share Posted September 21, 2019 Thankyou . I understand now. Now that Pictures can be posted this might explain the difficulty. When the feeler gauges are used to measure the gap in this Position I can get exactly 1,0 mm which goes right through Quote Link to comment Share on other sites More sharing options...
Antonnick Posted September 21, 2019 Author Share Posted September 21, 2019 and when I use the gauges in the central Position I can measure 1,4mm so _ Quote Link to comment Share on other sites More sharing options...
RobPearce Posted September 21, 2019 Share Posted September 21, 2019 How tight are those nuts? Does the 1mm apply to both sides? To be honest, the flange isn't important for the clearance, just for avoiding leaks. However, if your nuts are tightened enough to be distorting the flange (by 0.4mm is not impossible) then you want to use to centre reading, but if they're loose you want the edge reading. Incidentally, is that a "spawn of the devil" external rocker oil feed in the picture? Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted September 21, 2019 Share Posted September 21, 2019 I would do that procedure with the distributor removed from the pedestal. It's presence just makes things harder. Nick Quote Link to comment Share on other sites More sharing options...
.thumb.jpeg.b15b81ef10abeea1c3039ae03c4a9f3a.jpeg)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.