1993 Dt65 crankshaft disassembly

[Frazys]

Hi guys, I have a 1993 dt65 that I’m rebuilding. I have the crankshaft out and want to change the connecting rods bearings as well as all the other bearings. We tried to use an old bearing separator behind the main bearing and attempted to press it up towards the lower section of the crankshaft assembly so as the bearing was flat against the cast of the assembly. Sadly i think the separator we have at work is a bit old, beaten up slightly to big and ended up pulling the outer race of the bearing instead. I’m going to get a new separator from the auto store tomorrow and have another go but I can’t find much information in the workshop manual on disassembling the crankshaft assembly.
Is this the correct procedure for disassembling the crank or should I try to press the lower conrod pin first, this seems odd as there’s not enough room for the pin to be removed fully but could maybe move enough to remove the conrod but I will still need to replace the one main bearing I destroyed anyway.
Any ideas on the procedure for crankshaft disassembly?
Also will I need to get it balanced? The local engine spe******t said it can be balanced with the rods installed, so does that mean assembling without the rods and balancing, then disassembling and reassembling after? This doesn’t sound like it makes much sense. Does it have key ways to line the upper and lower assemblies?
Thoughts? Thanks

[Solarman]

I would have rebuilt mine, dt140's, if i could have separated the connecting rod journals/pins? I think the crank shaft screws together at each connecting rod journal to replace them, and also think the crankshaft screws together under the main bearings between cylinders 1 and 2, also at/under main bearing between 2 and 3.

I couldn't find any place (machine shop/crank rebuilder) anywhere that would try to rebuild mine.

Then tried to purchase the parts and complete new assy from Suzuki, but NLA. So I basically gave up on rebuilding.

Good luck, post back on what you do, if able to get it separated. I would like to find someone that can rebuild the cranks.

[Frazys]

Multi-cylinder pressed pin crankshaft disassembly.

So I asked the engine spe******t near by if he could rebuild my dt65 crank.... He laughed and said “sorry no” apparently thes old school pressed pin shafts take to long to rebuild and the labour involved can get out of control. Luckily I am currently working at as an mechanical engineer so I have the machinery required. He gave me a few pointers and the main thing was to mark everything And make a jig if possible to make sure you can also assemble it. I had it all wrong and rushed my first attempt which I stuffed one of the main shaft bearings, so hey take your time. I tried to keep the shoes together to press the conrod connecting pins out after.

The correct process was to start at one end and use a large bearing splitter under the first half of the shoe so the conrod can align between the 2 halves of the splitter and press the pin through the shoe. I used a work mate to pump the hydraulic press as I got ready to catch the shaft so as not to damage it. Once the first shoe is released, the main Center pin of the shaft is exposed and easy to access. Same process with the splitter (use the flat side of the splitter against the shoes surface) and start to press the pin through the shoe. Before pressing completely through the shoe, mark the side of the pin and where it enters the shoe to assist when realigning the shaft for pressing when assembling.
The bearing in the top section of my crank was still good and although I would prefer to change it, it is more work and something extra to go wrong so I’ve left the top section assembled.

Hope this helps anyone else attempting this

[Smokindave]

I have the same issue with my DT 90. I don’t have access to a hydraulic press and all I get from parts suppliers is” can’t help” or “ unavailable”.