hpi nitro .15fe mt truck /traxxas pro 15 help...

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flathead31coupe

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iam helping a young kid with his first nitro truck..hpi mt. the .15 fe engine was bad when he got it... i bought a traxxas pro .15 not realizing its a short shaft...of course the clutch wont wort or the mounting of the engine, advice or opinions welcome..can i get the parts to use the pro.. or will any of the 15 fe parts interchange thanks
 
You can get little stand off mounts and a clutch nut adapter that should work. I had a nitro MT many years ago and put an OS 18 CV-R(X) in it.

Adapter: https://www.rcplanet.com/Traxxas_Clutch_Adapter_Nut_p/tra4844.htm
Should get a couple shim kits so you can get the flywheel/bell lined up right: https://www.rcplanet.com/Associated_RC8_Clutch_Bell_Shim_Set_p/asc89148.htm
Don't forget to get bearings that will fit your bell, or you may need to get a new clutch bell that will work. If memory serves, the bell/bearing that came on that thing sucked. Used a plastic caged needle bearing. The bell is 1M pitch, which is odd for a smaller rig. MT2 stuff should work in that regard.

This might work for a mount: https://www.rcplanet.com/HPI_Engine_Mount_21mm_p/hpi86000.htm?gclid=CMLzlMn2tdQCFZS2wAod0nILdQ
That's for the MT2, so not 100% sure it will bolt right on.

I can't for the life of me find the engine mounts I used. They were just two cheap little cast aluminum blocks. You may have to get something and make it work.
 
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is there a better clutch assy you would suggest..flywheel ect.. this is what i have so far to use the stock bell https://www.rcplanet.com/order...does this look like what i need before i place an order thanks....
 
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i would like to order the right parts if anyone has a sujestion....before i place an order ....going from an hpi star .15 in a hpi mt truck..to a trax pro .15 short shaft
 
The bell you linked appears to just be a default order page, so I can't look at it.

Sorry my info is a little sketchy. Was 12 years ago when I had that rig.

I would assume that the bell/clutch/flywheel that works on the MT2 will work on the NMT. Perhaps you can find those parts more easily.

The big differences between the MT2 and NMT were spur/slipper, engine, arms, towers, shocks, possibly axles/bones/diffs. Very similar truck though, just updated a bit. The stock spur on the NMT sucked. It was very brittle and prone to stripping. I almost just bought the MT2 parts at the time to replace the entire center bit, but never dug into it completely to figure out what all I'd need and just sold it.

Just downloaded the exploded view for the MT2, it does appear to use the same parts as the NMT, except the stock engine in the MT2 came with a short shaft that required a pilot nut like I posted for you earlier:
2017-0611-MT2ClutchFlywheelExplosion.jpg


B046 was the bearing I didn't care for. The tooth count on the bell on that thing was small, so I guess that's why they went with that kind of bearing.

A normal CB is listed as an optional part for the MT2:
https://www.hpiracing.com/en/part/77103
Uses standard 5x10x4 bearings. However, that page also states that you have to then use a different motor mount. Guessing it moves the engine back a little bit or something so you can shim it properly. However, the mount is discontinued.

Mounts: https://www.hpiracing.com/en/part/86045

Those would probably work to install the TRX engine. Or something like them.
 
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cool thanks... the flywheel on the hpi had a notch in it and was stripped out, and is thicker, the long shaft had a notch in it as well and no cone....it was a long shaft... so looks like i need everything for the short shaft.. the bell i have is a 12t btw thaks for your help, its confusing tring to order the right parts when you do know
 
its a new traxxas pro ,15 short shaft..smooth.th hpi .15fe has a notch on both sides of the long crankshaft that the flywheel fits on to...ill get pics thanks
 

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Then all the parts listed in the photo I posted for the MT2 should work then. It uses a standard collet/flywheel/nut assembly. You put shims behind the collet to get the alignment right. When your done, the bell should almost touch the flywheel and the gear on the bell should line up with the spur properly. I suggest getting the shimming right before bothering installing the shoes. So then you don't have to "lock" everything down.Shoe/spring installation can be a pain, so no point in doing that more than once. Also, it lessens the likelihood of you accidentally stretching the spring(s) out.

Once you figure out the shims needed behind the flywheel, before the first bearing, after the outer bearing, then you can put locktite on the pilot nut, lock it down, put the shoes/spring(s) on, then the remaining bits. Don't forget locktite.

Usually, when tightening down the flywheel nut, a quick tug on the wrench will tighten it enough to then use channel locks on the flywheel to tighten it down fully. Make sure you clean the collet (inside/outside) and the taper in the flywheel with DA (alcohol/grease remover) before assembly or it will be tough to get things to lock up how you want. Some wrap the flywheel in a rag so as not to mar it up for starter wheels. I don't use starter wheels, so I don't bother with that anymore.

Also, a 4-way spark plug wrench usually fits the flywheel nut. However, most of the cheap ones are cast aluminum and aren't strong enough to not strip the wrench. I suggest using a good quality 4-way or a socket.
 
ok thanks...do I buy the flywheel adapter nut you first listed or the one in the pic,, all the parts in the pic look like what I have now except no collet and my flywheel has a notch that fits my crank shaft lol
 
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so far so good just the long shaft hpi flywheel has a shoulder on it and wont work on the short shaft traxxas pro short shaft
 

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