geoffbeaumont Posted October 3, 2005 Share Posted October 3, 2005 Just arrived home in a recovery truck The distributor drive has broken. Just as well that didn't go at the top of the Gap Road yesterday... The really annoying thing is that I'm going to have to work most of the way through the night to make up the time I lost this afternoon, and the only reason I haven't fitted the new EDIS ignition yet is the stupid amount of (unpaid ) overtime I've had to work recently. What am I likely to find when I remove the dizzy? Might it have sheared low enough down to drop the drive gear and swarf into the timing, or is it more likely to have gone up top? Up top would be good...if the drive shaft is still intact I can just leave the dead dizzy in to drive the oil pump. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 3, 2005 Share Posted October 3, 2005 Geoff, is it possible the drive gear pin has sheared or the gear engaging bit (the flat bit on the oil pump gear) has snapped off? Drive gear pin is easy, engaging bit would be new oil pump gears Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 3, 2005 Author Share Posted October 3, 2005 Geoff, is it possible the drive gear pin has sheared or the gear engaging bit (the flat bit on the oil pump gear) has snapped off?Drive gear pin is easy, engaging bit would be new oil pump gears Drive gear pin is certainly possible. Would the engaging bit result in loss of drive to the dizzy? If the drive gear pin has gone, will the gear be loose on the shaft? Or to put it another way, is the wretched thing going to end up in the sump when I withdraw the dizzy? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 3, 2005 Share Posted October 3, 2005 Drive gear pin is certainly possible. Would the engaging bit result in loss of drive to the dizzy?If the drive gear pin has gone, will the gear be loose on the shaft? Or to put it another way, is the wretched thing going to end up in the sump when I withdraw the dizzy? Hang on, I've got this ar*e about face haven't I, cos the dizzy drive drives the oil pump not visa-versa Err, ahem, well, <cough>... The pin would mean the oil pump still gets drive but the dizzy shaft doesn't. If it's sheared, then all the bits should stay put. If it's fallen out, which I'm not sure is possible in the available space, then you would likely have known about it as it wouldn't have sounded nice going round in the timing case Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 3, 2005 Author Share Posted October 3, 2005 Hang on, I've got this ar*e about face haven't I, cos the dizzy drive drives the oil pump not visa-versa Err, ahem, well, <cough>... The pin would mean the oil pump still gets drive but the dizzy shaft doesn't. If it's sheared, then all the bits should stay put. If it's fallen out, which I'm not sure is possible in the available space, then you would likely have known about it as it wouldn't have sounded nice going round in the timing case I should think there's plenty of space down there for the pin to come out - the timing case is pretty roomy. Given it's open to the sump at the bottom there's a good chance the bits of pin would end up down there without getting into the timing gear. FWIW the engine was at very low revs when it went, as I was stopping at a roundabout. On the other hand the timing has had a tendency to drift for a while now and when I had the dizzy out recently there was no sign of anything up externally, which would suggest the shaft might be sheared further up and has finally ground the broken ends smooth? Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted October 3, 2005 Share Posted October 3, 2005 Geoff, Usually it’s the dizzy gear that breaks around the area of the pin. A new gear can be got from Real Steel at about £50. They start to wear by the pin hole in the gear elongating and then finally breaking in the area of the hole . This is a much more common problem with a tuned engine at high revs, where the oil pressure has been increased as thus the loading on the gear is higher . Trouble is, you may have a bunch of broken gear ‘bits’ in the bottom of the timing case, so what essentially looks like a 5 minute job, may take some while. Ian Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 3, 2005 Author Share Posted October 3, 2005 Trouble is, you may have a bunch of broken gear ‘bits’ in the bottom of the timing case, so what essentially looks like a 5 minute job, may take some while. Ah, I have a custom tool for that job Constructed after I managed to drop a socket down the dizzy hole (yes, some mothers do have 'em...). Admittedly it's just a long screwdriver with a small allen key taped to the end, and the socket's still in the sump somewhere... It's a brass gear isn't it? So a magnet would be no use for getting bits out. Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 3, 2005 Author Share Posted October 3, 2005 Usually it’s the dizzy gear that breaks around the area of the pin. A new gear can be got from Real Steel at about £50. Craddocks have 'em for £25+VAT (part no. ERC1353 which I assume is correct - doesn't seem to have changed throughout the life of the engine, but my parts catalogue is missing the V8 engine post 1991). MM4x4 where I usually get my parts don't list them on their website. Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted October 3, 2005 Share Posted October 3, 2005 Geoff, Yes, that would be correct. The only different gears are those that fit pre SD1 engines ….. the difference being the oil pump drive is a male on the gear where as the post SD1 engines the oil pump drive is a female on the gear...... I'm full of useless information tonight:lol: The Real Steel gears are made from aluminum bronze alloy and are designed to wear instead of the camshaft gear on high revving engines Part no CX2694 (£55.30). Me thinks the craddocks part is a better option Ian Quote Link to comment Share on other sites More sharing options...
02GF74 Posted October 4, 2005 Share Posted October 4, 2005 Geoff,Yes, that would be correct. The only different gears are those that fit pre SD1 engines ….. the difference being the oil pump drive is a male on the gear where as the post SD1 engines the oil pump drive is a female on the gear...... I'm full of useless information tonight:lol: The Real Steel gears are made from aluminum bronze alloy and are designed to wear instead of the camshaft gear on high revving engines Part no CX2694 (£55.30). Me thinks the craddocks part is a better option Ian the diz. gear looks cast/machined part so would expect a magnet to pickthe bits up. the roll pin you can buy from craddocks - I can get you part no. & dims probably. Nothing should gone past into the oil pump butthe top part must be opento the sump - the part where the cam gear turns so that oil drops down. You may find bits in there! As said, you can get the diz. drive gear quite easily; Rimmer/Craddock. but it may come wiuthoutthe hole for the roll pin. You would then look at the old one and figure out where to drill the hole. Drill it si that is it slightly smaller through one side only, then line it up on the diz. shaft and counter drill to correct size all the way through - that way it will align - easy to mess it up. Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 4, 2005 Author Share Posted October 4, 2005 Well, thanks for all the advice on distributor drive gears, but it turns out to have been a bit academic. The drive gear's fine, and still turns the rotor arm nicely. Sitting down there next it, though, is a big chunk of cast something-or-other. Given I can see the inside of the timing chain, I'd say it's part of the top timing gear... I can't believe there were no nasty noises... Tried to take some photos, but you can't really see anything. Might get some film and have a go with the good camera. Time to find myself some temporary wheels Quote Link to comment Share on other sites More sharing options...
Fatboy Posted October 4, 2005 Share Posted October 4, 2005 Geoff, The original timing cog on the end of the camshaft is plastic I think... goodness knows whats happened.. What were the symptoms when it stopped ? Could it be the spacer off the end of the camshaft? - If its broken up, it might have allowed the drive gear to move up the shaft thus dis-engaging?? Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 4, 2005 Author Share Posted October 4, 2005 Geoff,The original timing cog on the end of the camshaft is plastic I think... goodness knows whats happened.. What were the symptoms when it stopped ? Could it be the spacer off the end of the camshaft? - If its broken up, it might have allowed the drive gear to move up the shaft thus dis-engaging?? Don't know - the only certainty is she's going nowhere until I've at least opened up the timing cover. Right now I'm sorting out the aquisition of an elderly eurobox to keep me mobile Quote Link to comment Share on other sites More sharing options...
Niall_CSK Posted October 5, 2005 Share Posted October 5, 2005 Donald has a good point there. I was hoping more along the lines of the plastic locking ring, not so lucky, good thing your name is not Jim I was about to post this and might as well in case it's of use to others. Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 5, 2005 Author Share Posted October 5, 2005 What were the symptoms when it stopped ? Oil light came on, then a couple of seconds later the engine stopped (probably just the time it took to spin down) - it was only at a few hundred RPM at the time. No nasty noises when it happened, or when I tried to restart it. Quote Link to comment Share on other sites More sharing options...
Niall_CSK Posted October 5, 2005 Share Posted October 5, 2005 or when I tried to restart it. It started again? Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted October 5, 2005 Share Posted October 5, 2005 Geoff,The original timing cog on the end of the camshaft is plastic I think... goodness knows whats happened.. The original camshaft dizzy drive gear is steel, but the original camshaft drive cog for the timing chain is indeed plastic . My money is still on the top of the dizzy gear having broken away from the pin. On engines where the oil pressure has been upped (and there’s no real need on the v8 design) it has been known for both the cam gear and the dizzy drive gear to wear to the point of disengagement even though these bits are only turning at half engine speed. Good bit of design really with the dizzy driving the oil pump ...oil pump drive failure means ur engines gonna stop . Geoff, when you strip off the timing cover you will most likely find that the timing chain has about a inch or so of slack as the genuine parts are known to exhibit this stretch problem, so new gears and chain will be required. Oh, and while you are in there you may as well pull the camshaft & lifters and renew those as well. It will entail a bit more work as the inlet manifold will need to come off to pull the lifters (that’s ‘hydraulic tappets’ in English ). The top end was not one of the best designs in terms of the materials used, but the lifters (being self adjusting) will hide phenomenal amounts of top end wear. Ian Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 5, 2005 Author Share Posted October 5, 2005 My money is still on the top of the dizzy gear having broken away from the pin. Even though I've already removed it, and it's fine? ^^^ Geoff, when you strip off the timing cover you will most likely find that the timing chain has about a inch or so of slack Bit more than that I'm thinking, seeing I can see it's not on the gear any more... Had another look tonight in better light - it's definitely not part of a gear down there. Jonathan suggested maybe the remains of a chain tensioner. Sounds about right - I'll have to take a look at the parts manual and see what's supposed to be there. As I've now aquired an old escort to put on the road for a bit, I might as well take my time and do the engine properly - means I can wait 'til I can afford the parts as well! It started again? Nope, but it turned over quite happily without making any nasty noises - I thought at first that it was a purely electrical problem. By the way, are the pistons and valves on the Rover V8 an interferance fit or not? As in, do I need to take the heads off and make sure there wasn't any carnage in there? Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 5, 2005 Author Share Posted October 5, 2005 Just had a look at the manuals - the Rover V8 doesn't have a tensioner on the timing chain. So what on earth is it?!! Quote Link to comment Share on other sites More sharing options...
Fatboy Posted October 5, 2005 Share Posted October 5, 2005 Geoff, I wish I had the drawing to explain my theory but... Camshaft has a boss that the plastic timing gear butts against. Then you fit a thick (+/-1/2") cast spacer then the dizzy drive cog, then a normal washer and the bolt. If the cast washer has broken up, it will have fallen down and may have allowed the timing cog to slip forward off the woodruff key. As it moves up the shaft, it goes onto a smaller OD and if there is enough slack,it could come off the cog as you have seen. The same "space" created by the broken spacer would allow the dizzy drive cog to move toward the timing gear thus disengaging from the dizzy. As the oil pump is fed off the dizzy drive, they will both stop and the oil light will come on. One of the flaws with the theory is that even a slack chain does not have a lot of play to allow it to move much off the centreline of the crank drive cog.. A fear I would have is that the camshaft would have stopped therefore you have the potential for some bent valves or at least push rods. I hope its simpler and therefore cheaper... As you've got another motor to run about in, I would not take the plunge and buy bits until you have sussed the full extent of the damage.. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 5, 2005 Share Posted October 5, 2005 Geoff - of course while you're there you may as well buy a hi-torque cam kit and duplex timing chain Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 5, 2005 Author Share Posted October 5, 2005 I wish I had the drawing to explain my theory but... Think you managed to explain it clearly anyway I guess I'm not really going to know the answer until I get the timing cover off. A fear I would have is that the camshaft would have stopped therefore you have the potential for some bent valves or at least push rods.I hope its simpler and therefore cheaper... As you've got another motor to run about in, I would not take the plunge and buy bits until you have sussed the full extent of the damage.. That's the plan - it'll probably off the road for a bit as my finances need to recover from the last couple of repair bills Since I've got to lay it up and strip the engine down anyway, I'll probably overhaul it properly - stick a new camshaft and timing gear in, oil pump cogs, rockers, etc. That'll run up a bit of a bill, but at least I can spread it out and do it as when I can afford the parts. Then I can fit the Megasquirt'n'EDIS when I build it up again. Wonder how much it would cost to switch to a serpentine belt? Hmm, timing cover, oil pump, new ancilary brackets, crankshaft(?) - probably more than it's worth I should probably spend the time and money putting a nice reliable rattle box in there instead Geoff - of course while you're there you may as well buy a hi-torque cam kit and duplex timing chain The thought had crossed my mind... Quote Link to comment Share on other sites More sharing options...
Niall_CSK Posted October 6, 2005 Share Posted October 6, 2005 My money is on Donald's diagnosis still, as he says you will loose quite a bit of oil pressure. Youcan still get a fair bit of lateral movement on a well worn chain & plastic gear, I know because I put one back together without the spacer just out of nosiness. Fridge is also right in that you may well find the camshaft & followers are past their best, a mild cam upgrade is not much different in cost to an original. Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted October 6, 2005 Share Posted October 6, 2005 Geoff, Oh dear….. this sounds as though it may get expensive . Another thought is … has the timing chain broken …….. they have been known to break on high mileage engines. Just rip it apart and keep us informed with all the gory details ……if I was closer I’d come and lend a hand. Ian Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted October 6, 2005 Author Share Posted October 6, 2005 One of my mates was fishing around in the timing case this evening - he was determined he was going to get the bit of broken metal out. Failed, but he has moved it enough to see what it is - it's part of the crankshaft timing gear, as I first thought. Looks like my car for some reason has the earlier cast gear not the plastic one which I think it should have for it's model year ('93)? Quote Link to comment Share on other sites More sharing options...
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