cummins driver

My Feedback: (31)

Hey guys. Im working on a Big Block T-Maxx for my father in law at the moment. He bought this truck as used and I am in the process of fixing it up for him[8D]

So, here is my problem... Being a big block, it has an SG threaded shaft. The flywheel is on, and obviously, the nut then tightens up on it, and the standard 2 shoe clutch just slides right onto the flywheel pins. The bell also goes on fine and spins freely. However, what happens is, the threads on the engine's crankshaft stick out past the flywheel nut/clutch. These threads hold the inner clutch bell bearing out away from the clutch/flywheel a few millimeters too far, and so when you start it and rev it, the clutch is allowed to come forward and slide 1/4 way off the flywheel pins because of the fact that the clutch bell sits so far forward.

Basically, the only option that I could come up with is to grind the engine's crankshaft threads back until they are flush with the clutch nut, then slide the bell back up against the clutch how its supposed to be, and put some extra shims on the crankshaft in front of the clutchbell to hold it in against the clutch.

Im just trying to make sure this is my only option. I was hoping not to have to do this, but I dont feel the clutch will work correctly if I leave it like this. We havent ran it yet but hope to soon, so hopefully we can get this fixed. Im waiting on some brake parts and once I have those and get them installed, the truck will be ready to go. Ill post some pictures soon. Thanks for any help!

Eric

Philly_RC_Guy

I put an extra clutch bell bearing on my SH.28 shaft and it stopped the clutch bell from sliding forward. I hope you can see it in the photo. I have been running my truck like this for about 6 months with no problems.

Snook Man

I think his problem is the clutch shoes are sliding forward inside the bell due to the bell not fitting all the way.

 

Either grind the crank threads or shim the flywheel forward.

Once you get the bell where you want it, you could then cut the end of the crank to eliminate the extra bushing if you wanted.

 

Eric,

Are you using the stock TRX clutch shoes with a BB?

cummins driver

My Feedback: (31)

Snook man, thank you for your help, that is indeed the problem. I can shim the clutch bell with no problems, its just that there is too much space and the clutch shoes are sliding forward.

Yes, the truck has a stock, or MIP 2 shoe clutch. Not sure which. The truck came like that though, so I guess we'll see how it does and ill find him a better clutch when this one lets go. haha

I may try shimming the flywheel forward. That would be easier than grinding the crank threads(I think). Ill just have to see if there is room to do that with the flywheel.

Thanks guys!

Eric

cummins driver

My Feedback: (31)

Hey Snook, thanks for the help. Got it taken care of.





There are a couple pictures. I ended up shimming the flywheel out just a little with a washer that fit the shaft perfectly. The clutch bell now fits perfect without a gap, so I think it'll be in good shape now. You can kind of see in the first picture the gap between the clutch bell and flywheel. Then in the other picture you can see the shiny washer behind the flywheel. He got the truck for a good deal so he has spent about $25-30 in parts now and once I get the brake parts and make the brake linkage, and a couple other small things, it will be good to go I think. Engine seems to run well anyways. I believe it is an XTM big block chassis kit on the truck. The tires arent glued to the rims. Dont know if he'll leave the big ribbed front tires on it or not

Eric

partisan

My Feedback: (1)

I have always used the nut adapter that came with my bug block conversion kit from dynamite. I cant find the part on their web site anywhere. I did have to cut the crankshaft off to accomidate the adapter.

The first pic is of the nut alone
Second is the crank, collett, flywheel and adapter.
Third is the collett and flywheel on the engine shaft with the little bit of thread left showing (i know a pin is missing from the flywheel, in the middle of a big rebuild and a lot of
projects.)
Fourth is the whole assembly on the shaft, then its just a matter of the clutch shoes and then the bearings and the bell.

I am trying to locate an adapter, no luck yet. Maybe someone on here will reconize it and know what part number it is.

partisan

My Feedback: (1)

this one might work, there wouldnt be an E-clip, just a cap head screw in the end to keep everything on.

http://cgi.ebay.com/Associated-Clutc...item53e4ecb9b0


I am not sure if the shim you put in is a great idea cause it might wear on the bearing weird, I am not an expert though

XtremeDad

Hey ERIC, What type of Engine Mount (blue) is that block mounted on ? if you know??? Thanks...Daryl...[8D]

cummins driver

My Feedback: (31)

Hey Daryl. The T-Maxx just has a standard 1/8 scale Buggy engine mount on it. Its identical to the engine mount on my Ofna nitro buggy, so id say about any buggy engine mount will work. The mount is adjustable so that you can slide the engine forwards and backwards to get it to sit where you want. Then it uses big 5mm bolts to bolt it to the chassis which are nice, because they dont strip as easily.

This is the same thing and you can find them in a couple different colors:

http://cgi.ebay.com/NEW-OFNA-ULTRA-M...item20b56950af

Eric

XtremeDad

HEY SPOT ON,,, That was exactly the type of Mount I was looking at for it, just wasn't sure,,, Trying to install a Savage 4.6 BigBlock in a stock 3.3maxx...
THANKS Alot for the reply back...
Happy RCing and MERRY CHRISTMAS... D... [8D]