A friend welded my diff on my mx5 and at first it was fine. Both wheels lock up job done, Tight circles get wheel hop job done. But now I've been driving it a while i can smell diff oil every time i get out my car so i know its leaking thats not my issue my problem now is i can do tight circles but have no wheel hop. Also trying to slide it, it acts like an open diff just the same as it did before. I tried reverse turning to make sure i had wheel and no wheel hop (that was in the dry as well). When he welded it we didn't put to much weld into it as we didn't want to transfer to much heat. We chucked a bolt in welded that and put a couple of pools of weld approx 1cmx1cm. Is it possible the welds have broke and the diff has now gone back to being open diff. Each opening of the diff was welded so its not like it was only welded in one place. Ive got a drift day on wednesday and need it sorted before then. thanks
take it out and check it, the last thing you want is a bit of weld escaping and jamming the crown wheel and stopping the diff whilst your driving to work. Bolts are plated and will be of different material / temper to the gears, the joint will carry high residual stresses and the joint will be inherently flawed, don't weld a bolt in there just get the weld right in the first place and fill the fucker up
Just got it in the air and one wheel can rotate and the other doesnt. Meant to have a drift day on wedmesday.
I would be having some serious consideration to where the 'welded' material has gone, and what it has done to your diff especially with bolts in it. When I welded my VLSD, I filled all 4 holes all the way up flush. That's welding the visible gears together, and then to the case of the VLSD component.
That gives you the weekend to reweld it tidy and stop the leak. This is my 4.3 Skyline VLSD for example
Nice one Sparky. Also note Joe that the ring gear on the MX5 VLSD sits over the hole you need to weld in, so can be difficult if your using a MIG with a large torch shroud. Also when your weld it do it with the stub shafts in place.
Yer the visible gears where welded together but the it wasn't then welded to case. I guess we will do that this time. I will take it all apart and inspect, Fingers cross theres no damage the crown gear.
ok will do. Thats what we found last time didn't have the stub shafts in and there was very small but definite misalignment. This is probably the knocking sound i have been hearing occasionally.
could it also be something a long the lines of the cup for the output to the driveshafts is not in properly or popped out so your effectivly running one wheel drive? i would of thought if the weld came adrift the diff would crap itself?
got the diff off today and took it apart. all is ok now. The weld broken and got mashed up in the LSD and shot bit of weld about 1cm x 1cm into the diff. Luckily it didn't get caught between the crown gear and the drive shaft gear. So reqelded it and tomorrow will be all back together. Filled all the holes with weld. It not as smooth as the diff pictured above but should do the job as I've only got 120bhp.
115HP is irrelevant, the 6 inch ring gear diffs don't have the best reputations. Some last, some destroy themselves. Mine has done rather well for the beating it has received thus far, but its a constant niggle in the back of my mind.
Yer i expect it to shit its self at some point. but for the cost of a new one and how quick they are to remove is doesn't bother me to much. Wednesday will be the test at DWYB
for future reference anyone else reading this thread.. if your going to weld your diff then get someone that KNOWS WHAT THEY ARE DOING a properly welded diff is safe as houses, one thats been done crap is dangerous, not to mention a waste of time
Thats a little bit harsh, my friend who has welded the diff normally welds and fills them up, After reading online a fair amount of people don't always fill them completely up. Its just a lesson learnt thing. No one knows everything and anyone who does is a cock, You learn something new everyday, hasn't caused any issue except from having to redo it so nothing been lost.
yes its a lesson learnt. luckily without anyone getting hurt. you dont "learn things" about mechanics on other peoples cars that are supposed to be on the road. you will end up killing somebody.
I'd say your lucky considering the possible outcome. Initial J made a good point, there things that you need someone with experience doing, say welding for any safety critical part like suspension or chassis to do. if he wasn't sure he shouldn't of done it.
