I started the process of replacing the diff before it explodes with my gearbox today.... How does this engine / gearbox mount located under the clutch come off It was getting really dark when I got the stage of removing the rear engine mount casting. The part is unbolted, the main engine to chassis bolts removed and the rear of the engine is lifted one or two millimetres from the subframe. But before I retired, I came to the conclusion that there may not be enough room to pull this part backwards off the long studs. Am I correct? If so, how does this part come off without lifting the whole engine? And to lift the whole engine without the rear subframe / chassis means removing the exhaust header. Confused and head in the WSM Thanks for any help. P Image Unavailable, Please Login Image Unavailable, Please Login
I hope this works out for you. I've only seen this job accomplished with the engine out and gearbox separated from engine. This could promote a lot of diff's to be changed. I didn't do it at my engine out, and wish I had. This approach offers an easier second chance. Don't know if this will help, but a master Ferrari tech who shared with me some great surgical in-chassis repairs told me he double nutted studs to remove them which allowed him to remove otherwise trapped assemblies. He never mentioned this specific in car diff replacement. I'm sure others with more experience with this will help.
You will need to remove the engine from the car. It is not necessary to remove the transmission from the engine. There are some more bolts under the flywheel that need to be removed.
CGR, do you mean there are fastenings indie the clutch housing? I.E. the clutch and flywheel has to come off? Cheers P
I'm not trying to replace the diff at the moment, simply trying to get the old diff out.... and trying a short cut. If it don't work I don't mind, I just need to make sure I am not wasting my time so I was hoping that someone would chime in to let me know I am wasting my time or not. I think I am getting to know my car really well now. From parking to having the whole back off the car down to the clutch and nearly the engine mounting off in 3 hours. My rates are cheap chaps, just buy me a plane ticket US bound , keep me for a couple of weeks and I may not need a return flight Actually on a serious note.. I was talking to a friend of mine and we concluded that for you US chaps it MAY be cheaper to ship your Testas over the the UK, have a full service inc. cambelts and the rest and ship back. I know that sounds silly but I have been really surprised at the cost of servicing in the US. Let me know if any of you US or Canadian chaps want me to look into this for you. At least I can put you on to what I consider to be the English experts over here. I'll leave it up to you but I am happy to help anyone who thinks it worth it. P
The engine cradle must be removed from the bottom of the car. The engine must be lifted out of the cradle and placed on a table. Remove the clutch, pressure plate and flywheel. This is the only way to get access to the differential. This is a big job! I would suggest waiting until a belt service and doing the swap at that time. Or is now a good time for new belts?
Good work Phil ! Just a photo of my engine (which is out) without gearbox ..... looks odd doesn't it ? We had to take the full cluth off ... (not too much of a job...) Is this any help ? Image Unavailable, Please Login Image Unavailable, Please Login
You can replace it with the engine in................but.............half shafts need to be removed, the clutch and flywheel need be removed, the rear motor mount x-member needs to be removed, I assume you have the airbox and exhaust removed?!? It's not easy with the engine in................but.........possible. The real obstacle will be setting up the pre-load and lash...........you do have it on a lift, yes? It is a chore to say the least!! While your at it check and see if your Brake Vacuum Pump Shaft is in one piece!! Hey by the way everyone I have Testarossa parts and a BMW convertible and a couple of airplanes for sale in FerrariAds...........so upgrade the TR, put the top down and start traveling as the crow flys!! Pitchin' Me
Kerry, I am just trying to remove the diff presently so I will do all the other work you recommend next winter. Once the diff is removed I will have time to remove the whole gearbox and do a box out diff set up properly. Engine out, valve clearance and cam belt change is something I wanted to leave to next year. Unfortunately I am beginning to wonder if I really should remove the whole engine and rear chassis. Once I do this I will be into next years plan which I didn't want to do yet. Ho humm if needs must.......... Any recommendations for a Testa Diff removal please chime in here, note: NOT a TR512. Cheers P
Phil, (jus a note) ... all these gearboxes are exactly the same: 512BB(i), Testarossa and 512TR ........ Engine removal is indeed different ... Good Luck .
I think thats the part that I am struggling with!!!!! Do I need to remove the clutch and flywheel to remove this part????? Once this is off and the drive shafts are removed, the Diff will come out with a couple of taps of a knockometer P
In my best English for the second time in two days..... BOLLOX Grrrrrrrrr. Ive been beaten again I will not loose............................ More posts tomorrow. P
Phil, I have done this with my engine in and replaced and shimmed a new diff Assy. To get the rear housing off you must take off the clutch plate and flywheel -no real drama but keep a good look out for any unusual little spring type washers around the clutch aligning studs. There are a couple of bolts behind the flywheel. The long studs that go all the way through the case will need to be removed. I found a specific stud remover that grips the threads and winds them out without damaging the thread. The reason you need to take these out is to enable enough rearward movement to clear the shorter studs before you hit the rear crossmember. Take plenty of photos. I have misplaced some of mine but will look for them. Support the rear of the engine and spread the load with timber. Once you have removed the rear support you will then be able to remove the oil spash guard and then will see the crown wheel and diff externals. To remove the diff you must remove the Left header and both side drive shafts. The right header can stay on as the RH diff support is not as deep as the left and slides out just missing the header. To get the LH side support out the quill shaft must be out and there is a small bolt that screws vertically up externally in the cover as well as the 8 external nuts. With both covers out and the diff laying in the bottom of the case jack up the rear of the engine with the front still attatched to the front mounts. It looks as if it will not go high enough without causing damage but will just do it. I loosened my header tank as this is the first point of contact- make sure your hood is up or your engine cover will suffer. when you get the engine as high as it will go lift the diff and rotate the LH side out and up as in the photo. It tends to only come out and go in one way with that crossmember just in the way. Once that is out you will see the end of the pinion. Good luck. Image Unavailable, Please Login Image Unavailable, Please Login
Phil, I assume you are pulling your stock diff to use for benchmarking of the new unit? In the long run I think you will find it more practical and time effective to drop the entire engine. I have tried "shortcuts" like these in the past. Got the job done but was far too painful and swore I would never do it again. I'll be going the full meal deal when the engine comes out for the 30k. It's the only way it makes sense to me.,
Spasso, ideally I would have done mine when I did my major and totally detailed my engine bay and replaced everything that needed replacing. Some 18 months after that my quill shaft broke and while I was in the process of replacing the shaft I decided to do the diff. Ideally I would set it up with the engine out but it is possible with the engine in just a little more frustrating at times. Overall a successful replacement with no damage to the engine bay and a possible saving of at least the labour to R&R the engine as most of the other work still needs to be done.
So on to Plan B....... I can either put it all back and wait for the next major and belt change next winter when the engine is completely out of the car and rear subframe. OR Continue as per Mikes (Testamon) example OR Take the engine completely out now..... I'm going for putting it back I could go for Mikes plan but as this was not my intention its probably not a good idea. The car is up on jacks and is not in a good location in my garage to allow me to do the work easily, been there before and still have the scars. I could go for the engine out. This means completely rebuilding the rear end, dropping the car off the jacks and turning the car round just so I can work inside properly. Then, when the engine is out not only do the diff work but do the valves, cam belts, pumps etc. and completely detail the underside of the engine and exhaust headers as well. I don't want to do all that work this year. So decision made, I will rebuild her tomorrow, I wonder what she sounds like with no exhausts on
So at this point you still cannot do an inspection of the carrier welds? If not I would refrain from driving it much. Roberts failure under such benign conditions was mind boggling.
But if you are not going to drive it - why not do the work now? Phil are you that gunshy? Curtis On the fence on this whole subject...
Granted winter is the best time to do such things. And a prophylactic change if it can be reasonably done is a good bit of insurance. Unfortunately it does not sound as if it is an easy task. Too bad there is no easy way to inspect. But your last post that I quoted seems to be telling him not to drive the car until after he does his major - which he did not plan until next winter. You said you are going to do your diff at your next major - a reasonable approach. But will you drive your TR as you did this past summer? Or are you going to accelerate when you do your major? Not trying to be accusatory or confrontational but wondering what you are thinking as you seem to be a very reasonable fellow. Very sorry to hear of Robert's (and Mel's) misfortune as I understand his TR was quite sensibly driven its whole life. Maybe his diff was made on a Friday afternoon...?
Robert and Mels failures were as much a surprise to me as it was to them i'm sure, I know they drive their cars very carefully and keep them well serviced. Its a risk we all take I guess. I decided to put things back because although my next major service is next winter, in reality its about 1,500 miles away as well, if that. So I am at risk, but I think a considered one. If I continue to take the engine out then there are many other things I want to do to the engine for which I will not have the time to do properly or the budget for all the parts I will need.
You are right Curtis. I won't be driving the car until next spring as she is tucked away in the garage for the winter. The plan to just change the diff was both possible in time and affordability. But, if I have to take the whole back off the car and get the engine out to change the diff then I might as well do valves, belts and pumps and all the other jobs as well. Unfortunately, I think I will run out of time as well as budget. As my wife is asking for work to be done on her XK and my daughters impending return home from tours abroad spells another service on her car I think I have enough on my plate this winter. Its a good job I enjoy this hobby, it would be better if I could get paid, I would have a fortune P.S. I can guess but what does "gunshy" mean P
