youngengineer Posted October 25, 2020 Share Posted October 25, 2020 I've researched this topic for the past 12 months and anticipate everything or atleast thought I did. I'm having issues clearing the bulkhead crossmember as the slave cylinder casting on the LT77 bellhousing fouls the crossmember. I've heard that the front xmember needed filleting in order for the front prop but nothing about the bellhousing... Could this be due to me being on a military chasis? Quote Link to comment Share on other sites More sharing options...
92a Posted October 25, 2020 Share Posted October 25, 2020 Hi , I had this issue and simply put a couple of 4mm aluminium spaces under the gearbox mounts ( I made my own engine mounts ) My engine etc is 50mm further forward to help clear the bulkhead as well, @ 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 25, 2020 Author Share Posted October 25, 2020 19 minutes ago, 92a said: Hi , I had this issue and simply put a couple of 4mm aluminium spaces under the gearbox mounts ( I made my own engine mounts ) My engine etc is 50mm further forward to help clear the bulkhead as well, @ I'm on standard series engine mounts. I've not yet fabricated the gearbox mounts. It feels to me as though the engine would have to go up a fair way tbh. Your idea of adding washers may just work but 4mm sounds a bit low. I think I would need at least 10mm just to avoid the bellhousing catching the crossmember as the engine was put under load. Quote Link to comment Share on other sites More sharing options...
Snagger Posted October 25, 2020 Share Posted October 25, 2020 Add some shims made of flat plate to the left engine and transmission mounts, between the brackets and the rubbers. That will move them up and to the right and will give you the clearance you need. There are no differences between standard and MoD spec chassis that would cause or avoid this fouling. You could try new mounting rubbers, just in case yours have squashed as they aged. That would have allowed the whole assembly to sit low on the chassis. 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 25, 2020 Author Share Posted October 25, 2020 (edited) Thanks Snagger. I'm on brand new mounts, the good quality soft ones too so that should be fine. If I lift only the LHS mounts (obviously this is much easier then doing both) , wont that make the engine and gearbox off level? Edited October 25, 2020 by youngengineer Quote Link to comment Share on other sites More sharing options...
Snagger Posted October 26, 2020 Share Posted October 26, 2020 It’ll only affect the level if you fit the shims with the right side mounting nuts tight. If you slacken the nuts off and wiggle the transmission and engine with the weight supported by a hoist or jack, they will settle again in the middle of the V formed by the chassis brackets, you have just narrowed the V (forcing the transmission higher) and moved its centre a little to one side with the shims. 1 Quote Link to comment Share on other sites More sharing options...
Bigj66 Posted October 26, 2020 Share Posted October 26, 2020 I don’t know much about the LT77 but is there just the one bell housing available for them? Would another version have the clutch slave cylinder in a different position? How have you fabricated your gearbox mounts or at least set the height you’ll use for them? 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 26, 2020 Author Share Posted October 26, 2020 2 hours ago, Snagger said: It’ll only affect the level if you fit the shims with the right side mounting nuts tight. If you slacken the nuts off and wiggle the transmission and engine with the weight supported by a hoist or jack, they will settle again in the middle of the V formed by the chassis brackets, you have just narrowed the V (forcing the transmission higher) and moved its centre a little to one side with the shims. Thats a good point. Thank you. I shall report back. Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 26, 2020 Author Share Posted October 26, 2020 (edited) 12 hours ago, Snagger said: It’ll only affect the level if you fit the shims with the right side mounting nuts tight. If you slacken the nuts off and wiggle the transmission and engine with the weight supported by a hoist or jack, they will settle again in the middle of the V formed by the chassis brackets, you have just narrowed the V (forcing the transmission higher) and moved its centre a little to one side with the shims. The washer trick worked. I put three on top of the rubber engine mount and three below which gave the engine a nice lift whilst still being able to fit a nut on both ends. Now the bellhousing clears the xmember with 20mm to spare. After 4 hours I still cannot get the box mated to the engine. No amount of pushing, pulling, prying will do it. I have chamfered the front of the spigot bushing and made sure the clutch is correctly aligned but still nothing. I'm using two jacks and an engine crane to align the box but it does not want to know about it. Any tips? Edited October 26, 2020 by youngengineer Quote Link to comment Share on other sites More sharing options...
Romahomepete Posted October 26, 2020 Share Posted October 26, 2020 2 long studs in the flywheel housing often helps Peter 1 Quote Link to comment Share on other sites More sharing options...
92a Posted October 26, 2020 Share Posted October 26, 2020 I've had a similar problem and the clutch drive plate spline was slightly damaged , I always try them on the gearbox input shaft spline before using them now, only takes a few minutes but I wasted several hours that day before realising 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 27, 2020 Author Share Posted October 27, 2020 I have fitted the clutch to the box and it does slide on just fine. Everything otherwise seems ok. Quote Link to comment Share on other sites More sharing options...
Wytze Posted October 27, 2020 Share Posted October 27, 2020 Is the friction plate centered to the spigot? 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 27, 2020 Author Share Posted October 27, 2020 It is, I have used a clutch alignment tool. Quote Link to comment Share on other sites More sharing options...
Wytze Posted October 27, 2020 Share Posted October 27, 2020 Do you have the gearbox in gear, to get the splines in line 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 27, 2020 Author Share Posted October 27, 2020 (edited) 16 minutes ago, Wytze said: Do you have the gearbox in gear, to get the splines in line I don't think so. I've removed the remote to facilitate fitting. It should be in neutral. Edited October 27, 2020 by youngengineer Quote Link to comment Share on other sites More sharing options...
Snagger Posted October 27, 2020 Share Posted October 27, 2020 You do have the clutch plate for an LT77 rather than the series box, I take it? Different splines on each. It’d be an easy mistake to make. 1 Quote Link to comment Share on other sites More sharing options...
Wytze Posted October 27, 2020 Share Posted October 27, 2020 10 minutes ago, youngengineer said: I don't think so. I've removed the remote to facilitate fitting. It should be in neutral. Get it in gear, first or second will be fine. If the transferbox is on, get that in diff lock. 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 27, 2020 Author Share Posted October 27, 2020 9 minutes ago, Snagger said: You do have the clutch plate for an LT77 rather than the series box, I take it? Different splines on each. It’d be an easy mistake to make. No its a LT77 clutch plate. Ive fitted the plate to the box and it slides on fine. 1 Quote Link to comment Share on other sites More sharing options...
Gazzar Posted October 27, 2020 Share Posted October 27, 2020 I've found that it's easy, if you are absolutely obsessive about alignment. Measure the distance all the way around and make sure it's 100% even. If this is impossible, and it can be hard to get this, if you aren't using an engine crane and load leveler, then persevere, you'll find that when it does go on it will be quick. Two studs either side does help. 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 27, 2020 Author Share Posted October 27, 2020 (edited) I finally figured it out. I was just about to give up after the 10th attempt and decided to take all the studs out and behold, the box went straight in with minimal effort. I noticed there was one additional stud which did not have a through hole on the LT77. You see, I had a S3 box fitted before the LT77 and it seems the bolt pattern was slightly different. Slightly embarrassing, two days later. Oh well. At least I'm really good at taking the box out now. Edited October 27, 2020 by youngengineer 1 Quote Link to comment Share on other sites More sharing options...
Wytze Posted October 27, 2020 Share Posted October 27, 2020 Yes, the series and defender have one hole in a different place🙃 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 28, 2020 Author Share Posted October 28, 2020 (edited) Ok so the day was going fairly smoothly. I've managed to shorten the rear prop and start making the extended gearbox mounts. I decided to reinstall the remote which i had removed to allow better access and to my surprise there is now an issue with gear selection.. I'm getting some gears but not all. 5th and fourth seem ok, I cant seem to get first or second. The selection feels weird. What should be neutral locks up the box completely and will stall the engine if I depress the clutch. Clutch has been bled and is actuating correctly. This happens with the engine off also so its not a clutch issue. I have removed the remote and put it in a vice and it seems to be working as it should. Any ideas? Please dont say pull the box again... Gear selection was working great just a few days ago. Edited October 28, 2020 by youngengineer Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 29, 2020 Share Posted October 29, 2020 It sounds like it is putting two gears in at the same time thus locking it up? Were the selectors in the correct position before you fitted the change mechanism? Someone who knows the LT77 should be able to tell from the pic I am guessing? 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted October 29, 2020 Author Share Posted October 29, 2020 5th gear seemed to be engaged which did not allow any other gear to be fully selected. I had a prod around in there and the 4th/5th fork was engaged when the remote was in neutral position. So just as you had mentioned! Quote Link to comment Share on other sites More sharing options...
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