Dannyb Posted October 15, 2018 Share Posted October 15, 2018 Having retired from the RBRR at JOG I have taken the gearbox out expecting a destroyed gearbox. But the gearbox looked fine so moved onto the clutch and soon noticed the flywheel was loose. The flywheel bolts had come loose with one being sheared off in the crank. The locating pin in the flywheel is missing and the bolts have eaten into the clutch springs. The flywheel bolt holes look elongated so a new flywheel will also be needed but much cheaper than a new gearbox I suppose. Just got to try and get the sheared bolt out of the crank. Have a look https://www.youtube.com/watch?v=d-M3s8AQCy8 😳 Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted October 15, 2018 Share Posted October 15, 2018 Torque wrench AND loctite needed for flywheel bolts. The locating dowel matters too as it prevents fretting and loosening that way. I imagine the sheared bolt will come out ok seeing as they were undoing themselves! Nick Quote Link to comment Share on other sites More sharing options...
Dannyb Posted October 21, 2018 Author Share Posted October 21, 2018 Spent some time on it today. The locating dowel was snapped off halfway in the crank. I have managed to drill it out. The broken bolt i more is another story. While drilling it it moved further down the thread so was loose although would not come out with a stud extractor as it looks like the thread at the top is a bit iffy. At the moment the it stuck at the bottom of the thread and for some reason the drill is not making any progress. don't know if it has a git of hardened stud extractor stuck in the center stopping the drill. I have cleaned all the bolt threads with a tap including the one which is blocked which has about 1/2" thread clear. I had to give up and go back to it another day as laying head first under the dash on bare metal floor with the handbrake in my ribs has taken it toll. Quote Link to comment Share on other sites More sharing options...
RobPearce Posted October 21, 2018 Share Posted October 21, 2018 I've had limited success with stud extractors. With stubborn remnants I usually resort to welding a small nut onto it to give something to turn. The extra heat often helps free it up, too. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted October 21, 2018 Author Share Posted October 21, 2018 Because it's down the thread I cant get in with a welder. I shall have to persevere with drilling. Quote Link to comment Share on other sites More sharing options...
sparky_spit Posted October 22, 2018 Share Posted October 22, 2018 Might be a bit late now but a left hand drill bit would have been better. Might still be a better option than a normal right hand one? Quote Link to comment Share on other sites More sharing options...
Clive Posted October 22, 2018 Share Posted October 22, 2018 The mention of a bit if if extractor may have broken off worries me. If it has I doubt it will drill out. If if is fairly deep into the stuck bit of bolt, a bigger lh drill may work. I take it you have cleaned the thread up on that hole now. And a bolt winds in easily. Quote Link to comment Share on other sites More sharing options...
Clive Posted October 22, 2018 Share Posted October 22, 2018 The mention of a bit if if extractor may have broken off worries me. If it has I doubt it will drill out. If if is fairly deep into the stuck bit of bolt, a bigger lh drill may work. I take it you have cleaned the thread up on that hole now. And a bolt winds in easily. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted October 29, 2018 Author Share Posted October 29, 2018 I have now managed to drill out the broken bolt stud. I ended up using three different size drill bits with different cutting angles. I then used a drill just wide enough to re-tap. Before I used it I ground the cutting edge along the drill to make it narrower than the cutting tip so not to bugger the rest of the thread. I re-tapped and fitted the new flywheel and bolts with Loctite and tightened to 45 lbs ft. This is when I noticed the crankshaft pully nut had also come loose. Not sure if I should lock the flywheel and torque the nut or put the gearbox back on and lock the output shaft with it in gear before connecting the prop. Quote Link to comment Share on other sites More sharing options...
Clive Posted October 30, 2018 Share Posted October 30, 2018 I would lock the flywheel now, that way you don't stress the gearbox (should be OK, but if possible to avoid I would.) I tend to just use an air wrench to wang a lot of these bolts up, a few dugga duggas and that is tight. But I am starting to use thread lock more often. Never used to have issues with stuff coming undone, but mt starter motor keeps coming loose (bolts go into tapped threads in the bellhousing) and last summer going to CLM the starter itself started to come apart. Then on border raiders I lost the rear caliper slider pin bolts on one side. I think I have a gremlin living in my garage. Quote Link to comment Share on other sites More sharing options...
RobPearce Posted October 30, 2018 Share Posted October 30, 2018 Quoted from Dannyb- Not sure if I should lock the flywheel and torque the nut or put the gearbox back on and lock the output shaft with it in gear before connecting the prop. I never rely on the gearbox for this. I have a flywheel lock that bolts in place of the starter motor and engages on the ring gear. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted October 30, 2018 Author Share Posted October 30, 2018 Rob, do you have picture of the lock. Is it a bar shaped to fit the flywheel teath with two holes that match the starter motor mounting holes.. Quote Link to comment Share on other sites More sharing options...
RobPearce Posted October 30, 2018 Share Posted October 30, 2018 Quoted from Dannyb- Rob, do you have picture of the lock. Is it a bar shaped to fit the flywheel teath with two holes that match the starter motor mounting holes.. Something like that. The teeth bit sticks out the back so you bolt it to the front of the engine back plate - thus making it useful while the engine and gearbox are still in the car, too. I welded it up out of some 50x6mm and some 10x3mm bar I had lying around. I'm sure I have a photo somewhere but I'm not at home to check at the moment. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 11, 2019 Author Share Posted February 11, 2019 Cars all back together but won't start. fuel and spark but no compression. Took valve cover off and it looks like the valve timing is out. So the timing chain (duplex) must have jumped a few teeth. Put the flywheel lock back on which I made to tighten the loose crank nut and now cannot remove it. Will try getting a length of tubing tomorrow to give it more leverage. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 12, 2019 Author Share Posted February 12, 2019 Crank nut off with the help of a 4 foot tube, after removing the timing I could see the D shape Key was missing. Unable to find any remnants so could have gone down the oil drain slot into the sump. Quote Link to comment Share on other sites More sharing options...
WIMPUS Posted February 13, 2019 Share Posted February 13, 2019 Quoted from Dannyb- Crank nut off with the help of a 4 foot tube, after removing the timing I could see the D shape Key was missing. Unable to find any remnants so could have gone down the oil drain slot into the sump. That's not good ! 😲Hope you can sort it out, but seems to be a sump and timing cover off job ! Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 14, 2019 Author Share Posted February 14, 2019 Found what was left of the Woodruff key. It was embedded in the rubber seal of the crankcase cover. Looks like I will have to get another crank pulley, as the face is scored where the seal runs. Also the slot in the pulley has taken a bit of a beating. Also you can see the slot in the crank has also taken a hit. Quote Link to comment Share on other sites More sharing options...
sparky_spit Posted February 14, 2019 Share Posted February 14, 2019 Have you any ideas of the root cause of the failure Danny? Sheared flywheel bolts and loose crank-nut/sheared woodruff key cannot be separate failures. Do you know if the thrust washers are still in place? Fingers crossed that they are. You may be able to get the crank nose metal-sprayed/welded but if the thrusts have dropped out it might have completely wrecked the crank. In your bottom picture, behind the shim on the crank nose, there looks to be a rubber oil seal? Or is it just the lighting that makes the chamfered end of the front journal look like an oil seal? If it is an oil seal, then that should not be there - see https://www.canleyclassics.com/triumph-spitfire-mkiv/1500-crankshaft-piston-conn-rod-and-flywheel Looking at the witness marks on the crank around the keyway, it looks as though the pulley has not been sitting far enough onto the crank, and has left the rearmost 5 - 7mm of the key not actually in the keyway. Or maybe those marks were made after the crank nut came undone? EDIT.... On second thoughts forget that. I forgot that the lower timing chain sprocket shares half the woodruff key with the crank pulley. Quote Link to comment Share on other sites More sharing options...
thescrapman Posted February 15, 2019 Share Posted February 15, 2019 I think your crank and pulley may be fooked. :-( Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 15, 2019 Author Share Posted February 15, 2019 Quoted from sparky_spit- In your bottom picture, behind the shim on the crank nose, there looks to be a rubber oil seal? Or is it just the lighting that makes the chamfered end of the front journal look like an oil seal? Yeah it's the light that makes it look like rubber. I Have sourced another pulley wheel and will have to take the sump off to check the thrust washers are still in place. waiting for new woodruff key and timing cover gasket to arrive. I think the problem was started with the flywheel end and the vibration loosening the crank nut. normally I would have stopped at the first sign of trouble, but being the RBRR I pushed my luck for too long. I'm hoping the woodruff key will still fit in the crank. May have to think about sticking it in with something or maybe a weld. Got nothing to lose. If the crank is shot then I will rebuild the original engine I have in the garage. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 16, 2019 Author Share Posted February 16, 2019 Checked the end float today on the crank. 0.07mm so 0.04mm over the limit. Not enough I would have thought to suggest the thrush washers had fallen out but worn. Oh and the bit of metal that I thought was the remains of the Woodruff key turns out to match the hole in the pully. Does anyone know what thickness the standard thrust washers are. Quote Link to comment Share on other sites More sharing options...
WIMPUS Posted February 16, 2019 Share Posted February 16, 2019 Here you go.... Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 16, 2019 Author Share Posted February 16, 2019 Thanks Wim, With a bit of luck I will get the sump off and get the shims out during the week. I can then work out what size will be needed. Quote Link to comment Share on other sites More sharing options...
Dannyb Posted February 19, 2019 Author Share Posted February 19, 2019 Sump off and all clean. No lumps of metal and magnet drain plug all clean. Rear crank bearing shell shell like new. Took out the shims. The rear shim is pitted and under size. The front shim still looks good. Both are standard. So now to order a new pair. Quote Link to comment Share on other sites More sharing options...
sparky_spit Posted February 19, 2019 Share Posted February 19, 2019 No sign of the woodruff key? It has to be somewhere. 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.