theredkite Posted June 4, 2014 Share Posted June 4, 2014 I'm trying to replace the plugs on my Scorpion, but the rear one nearest the fighting compartment is pretty solid. (Numbered 1 in the photo, as you can see it's already starting to deform under my hamfisted efforts!) It's pretty hard to get at with anything worthwhile, so I want to find out my options before I either give up on it or do some serious damage. Firstly, is there any kind of tool - other than the right spark plug socket! - for removing the plugs on a J60? Secondly, I might be able to get a reasonable hold on it if I could unscrew the cable at the nut I've marked 2 on the photo - the nut does unscrew but the cable feels pretty attached to what's inside, and again I don't want to do any serious damage! Can I safely separate the cable there? Thanks for any help, and my apologies for posting a picture of such a filthy engine, I promise if I can get the plug out I'll post a picture of everything looking squeaky clean! Mike Quote Link to comment Share on other sites More sharing options...
robin craig Posted June 4, 2014 Share Posted June 4, 2014 Number one is the correct place. Use a flare nut spanner for the job but only after making a dam out of plasticine aka modeling clay and flooding the resevoir formed with diesel fuel to act as a penetrant. Think about it, the water has corroded the threads and the same will have happened on the spark plug itself. Use the ponding effect on the top of the engine to now retain the diesel. Hurry up and slow down and use a healthy dose of patience also. R Quote Link to comment Share on other sites More sharing options...
theredkite Posted June 4, 2014 Author Share Posted June 4, 2014 Many thanks Robin. I'll begin the process and let you know how I get on! Mike Quote Link to comment Share on other sites More sharing options...
martinwcox Posted June 4, 2014 Share Posted June 4, 2014 Ditto on Robin's remarks. It took me a week of filling the valley and soaking with Kroil to get the plugs out. Remember it's an aluminum head, the use of any power tool to try to remove the plugs will not go well. Also, remove all crap etc. from the surrounding area before pulling the plug as said crap etc. WILL enter the cylinder. Patience here is your best friend. Martin. Quote Link to comment Share on other sites More sharing options...
theredkite Posted June 10, 2014 Author Share Posted June 10, 2014 Thanks for the tips, guys. Unfortunately after a week it hasn't budged - one of the bolts on top of the block makes it impossible to attach even a flare nut spanner onto it (which I suspect is why it's been allowed to get so firmly stuck over the years). I've replaced the other five plugs and I'm going to try to get it started with five good ones and 1 stuck one! I've a couple more questions, which I'll put in a different thread so it has the right topic! Quote Link to comment Share on other sites More sharing options...
andym Posted June 10, 2014 Share Posted June 10, 2014 Time for the fly spray trick perhaps? Andy Quote Link to comment Share on other sites More sharing options...
Sidewinder Posted June 10, 2014 Share Posted June 10, 2014 Andy, what's the fly spray trick?! James Quote Link to comment Share on other sites More sharing options...
martinwcox Posted June 10, 2014 Share Posted June 10, 2014 Have you tried a crows foot wrench on number 1? You can get new cable sets if the need arises. I bought a very deep wall socket to remove the plugs so as to clear all the obstructions as in head bolts etc. M. Quote Link to comment Share on other sites More sharing options...
andym Posted June 10, 2014 Share Posted June 10, 2014 Andy, what's the fly spray trick?! James It's been suggested that fly spray will unseize steel and aluminium that have corroded together. I haven't managed to try it myself yet ... Andy Quote Link to comment Share on other sites More sharing options...
timbo Posted June 11, 2014 Share Posted June 11, 2014 I suspect you need the type of flare nut/ crowfoot that can be driven by a 3/8 drive, rather than a spanner. You may find you cant get the angle on the spanner to move it, esp as no 1 is quite cramped. Quote Link to comment Share on other sites More sharing options...
robin craig Posted June 11, 2014 Share Posted June 11, 2014 Considering the wires are available now that you have gone this far and no joy I would seriously consider cutting the fitting that is between 1 and 2 and making way for a good deep socket of an impact not chrome type and put some real beef to it with some penetrant. Focus on the real target which is the plug, sacrifice the wiring. It may also scare the plug as to the lengths you are prepared to go to and it may give up and come out, just like lighting a ciggy to make a bus arrive. R Quote Link to comment Share on other sites More sharing options...
theredkite Posted June 14, 2014 Author Share Posted June 14, 2014 Thanks again for all the suggestions. I have to move the poor wee beastie in the next couple of weeks, so I'm trying to avoid as much "damage" as possible. Anyway, having replaced five of the six plugs and pumped out all the old fuel, replaced it with some lovely new 97 unleaded, nothing. I then tried putting some of the new fuel directly into the carb, and she fired up at what seemed v high revs (the counter said 2,000 but I'm not convinced...) So the electrical system is working okay, may be a problem with the carb still, but I need to top up the coolant level. On to a new thread (and thanks again!) Mike Quote Link to comment Share on other sites More sharing options...
timbo Posted June 15, 2014 Share Posted June 15, 2014 Mike Is your fuel pump working? It should make a ticking noise when you put the engine on. This should start off quite rapid and then slow a little as the fuel comes through. The other easy check is the fuel filter in the rear right of the fighting compartment. Tim Quote Link to comment Share on other sites More sharing options...
Tiffy_massive Posted June 15, 2014 Share Posted June 15, 2014 Don't forget that the electrics on Armd Vehs were mainly shielded to prevent interference with comms eqpt. No reason why you cannot replace the lot with a good set of un-shielded leads as you would find fitted to any Jag car running the same engine. Quote Link to comment Share on other sites More sharing options...
theredkite Posted June 17, 2014 Author Share Posted June 17, 2014 Tim - thanks for the suggestion. Yes, the fuel pump is working fine, I spent a couple of happy hours pumping out the old fuel into assorted jerry cans. Tiffy, I'm not keen at the moment on changing the leads, might be an idea when I have a bit more time, but that distributor looks a bit evil to get at (and I always drop stuff in the engine bay!) So, the electrics are (kind of) sorted. The situation now is as follows: the beast isn't easy to fire up, but if I pump a little fuel in first and then fire the ignition, the engine quickly races to over 4,000 revs (and I have to shut everything down). I've tried moving the idler screw, to no effect, and it isn't the throttle linkages (the throttle has no effect at all). It's all very all or nothing, can anyone suggest why it's doing this, I'm guessing it must be something to do with the carb? Cheers, Mike Quote Link to comment Share on other sites More sharing options...
timbo Posted June 17, 2014 Share Posted June 17, 2014 Mike Firstly is the cold start lever stuck in the on position (ie pushed over to the left towards the driver)? If not then if it were me I would whip the decks off (if not already) remove the carb, and give it a general poke/ clean to see what that does. In my experience once you have accepted the need to remove the decks it is not so big a job, and makes everything hugely easier.... Look forward to hearing progress. Tim Quote Link to comment Share on other sites More sharing options...
theredkite Posted June 17, 2014 Author Share Posted June 17, 2014 Tim It feels like I'm making progress, thanks to the help I'm getting here. I now know it's not the electrics, the fuel or the fuel pump - narrows it down nicely! Yes I've got the deck off, and I've had the carb off before. That's not to say I haven't somehow fouled it up, but I didn't dismantle it at all, just gave it a good spray with carb cleaner. The cold start seems to be working fine, the mechanism on the front of the carb moves easily enough. I've tried the throttle with the engine switched off and the top off the carb, although the two jets don't spurt brilliantly equally, fuel does come out of both into the main chamber of the carb. What's weird for me is the way it suddenly shoots up to such high revs - I guess something is either stuck or flooding it? I'm ready to take the carb off again (hate that job - I know sooner or later I'm going to drop something somewhere I shouldn't ) but I'd love to have a suggested cause before I do! Cheers for the help and support, Mike Quote Link to comment Share on other sites More sharing options...
martinwcox Posted June 17, 2014 Share Posted June 17, 2014 I would have suspected the diaphragms, maybe the jets are clogged. This post may be of help: http://hmvf.co.uk/forumvb/showthread.php?22483-SOLEX-40-NNIP-Carburettor-Parts-Pictorial&highlight=solex Martin. Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted June 17, 2014 Share Posted June 17, 2014 I cannot see how the engine would rev up to full revs if the butterflies are closed, not enough air going through. I suspect the spring that hooks on the throttle arm ball pin has come adrift allowing the throttle to be open. Quote Link to comment Share on other sites More sharing options...
Diana and Jackie Posted June 17, 2014 Share Posted June 17, 2014 Remove fuse from rev limiter, fuse is adjacent to ignition coil, if it fixes it you have a faulty rev limiter. Diana TimIt feels like I'm making progress, thanks to the help I'm getting here. I now know it's not the electrics, the fuel or the fuel pump - narrows it down nicely! Yes I've got the deck off, and I've had the carb off before. That's not to say I haven't somehow fouled it up, but I didn't dismantle it at all, just gave it a good spray with carb cleaner. The cold start seems to be working fine, the mechanism on the front of the carb moves easily enough. I've tried the throttle with the engine switched off and the top off the carb, although the two jets don't spurt brilliantly equally, fuel does come out of both into the main chamber of the carb. What's weird for me is the way it suddenly shoots up to such high revs - I guess something is either stuck or flooding it? I'm ready to take the carb off again (hate that job - I know sooner or later I'm going to drop something somewhere I shouldn't ) but I'd love to have a suggested cause before I do! Cheers for the help and support, Mike Quote Link to comment Share on other sites More sharing options...
fv102 Posted June 18, 2014 Share Posted June 18, 2014 Highly unlikely to be the rev limiting fuse, this prevents the engine going above 4750. If they are faulty they either just don't work or will cause the engine to mess around poping and banging below the magical 4750. As Richard points out the raise to 4000rpm suggests the throttle spindle is in such a position that the fuel is being sucked into the engine. From memory usually if the cold start device is on the engine will attempt to flood it'self unless the throttle butterflies are open. If the throttle return spring is in position then it is possible the throttle spindle is stuck open or not fully returning to the closed position. The accelerater pumps only increase fuel for a very short period of time and require operation of the throttle for them to operate as they are connected directly to the throttle spindle. Not unusal for both the jets to be slightly different. D Quote Link to comment Share on other sites More sharing options...
GeePig Posted June 18, 2014 Share Posted June 18, 2014 I agree as well, no amount of overfuelling or ignition is going to get the engine to 4000 rpm - either the throttle butterflies are too far open or there is a large hole in the intake manifold (like if you had removed a blanking plug or something). It could be a cold start device holding the throttle open, sticky throttle or broken/weak/missing/etc. throttle return spring, or sticky throttle cable. Is it possible to safely look down at the carbs while someone starts the engine for you? trevor Quote Link to comment Share on other sites More sharing options...
theredkite Posted June 18, 2014 Author Share Posted June 18, 2014 Success! And I definitely couldn't have done it without the advice here - thanks. First I checked the cold start and throttle butterflies at rest - they both looked "pretty much" closed (v hard to see the cold start one from above), but in any event I moved the cold start right over to rest, using the lever on the carb not the connector in the driver's compartment. Fired her up - straight up to 2,500 revs (an improvement but still not right). Then by pulling back on the throttle control (I hadn't been near the pedal) managed to bring it down to 1,000 revs, and after a while right down to 600. It currently "idles" at around 1,500. When the engine was warm I tried adjusting the idle screw at the bottom rear of the carb, but it made no difference. So I guess the answer is, as suggested above, that if the cold start and throttle butterflies are open at all the engine was flooding itself. I don't think I would ever have worked that out from looking at the butterflies, which as I say looked closed/nearly closed. (And previously I'd tried pulling the throttle control back as far as it would go while it was over-revving, with no success, I guess because the cold start butterfly was a little open?) I'm going to keep the deck off for a while and check her regularly. The opportunity to give everything proper attention will come after she's been moved to her new home in a couple of weeks. Incidentally I reckon the original problem I had, of not getting her to start, was due to old fuel. Having not been driven much in the past three years, when I pumped out the old fuel it looked quite opaque, v different to the new stuff I put in. I can't be completely sure, but I reckon it was tired fuel that was my original problem, that's (another) lesson learned for me! Many many thanks - couldn't have done it without this forum . Mike Quote Link to comment Share on other sites More sharing options...
GeePig Posted June 18, 2014 Share Posted June 18, 2014 Well, that is just great news! When the engine was warm I tried adjusting the idle screw at the bottom rear of the carb, but it made no difference. If that is a screw in the body of the carb, then the idle fuel circuit might be blocked - the hole where the fuel comes out is near the throttle butterfly when the throttle is nearly closed and easily fills with corrosion or other gunk that falls into the carb. If the screw is on the operating mechanism, something else is probably stopping the throttle from shutting fully. trevor Quote Link to comment Share on other sites More sharing options...
timbo Posted June 18, 2014 Share Posted June 18, 2014 Well done all very satisfying.... But did you get the plug out..!? Quote Link to comment Share on other sites More sharing options...
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