Gear Noise

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I figured out what the gear noise was......dammit, the diff gear and the transfer gear weren't lined up properly. I ground those gears down on the diff a bit. How close are they supposed to be together? Anyone have a good way to do this?

Off to order a new Diff gear. Fantastic!
i saw that on my truck, i fixed it before it had a chance to do damage though. I just use a peice of note book paper to adjust mesh. loosen adjustment screws pull the gears appart from each other put the peice of paper between them, then push them together and tighten the bolts. then roll the peice of paper out of them. you want to make sure you crush the paper between the gears firmly. so that you can see the gear imprint when you remove the paper.
A standard business card will do great for the mesh. If the motor mount screws come loose the motor will pull forward and away with the mesh like it happened to you. Make sure if the small gear is banged up at all you get that one as well, its only another 7.00 more and it will make sure that the fit and mesh will be correct. Could be worse just the ring gear on the FG is more then both gears together on the FH's.:(
Good advice, thanks guys!

I found another issue. The alloy engine mount. The part of the mount where the bulkhead brace attaches to by the short screw is stripped. How it became stripped is beyond me. I never tightened the hell out it, just put on threadlock and tightened. I wonder if that caused some of my issues with the gear....probably. I have another screw, same threading and longer. It screws right in and tightens up nicely.
Super, no one has the transfer gear in stock (14 tooth) for the Firehammer MT. Late f:cursing:ing June its due. Tower and TQRcRacing both have the 16 tooth Firehammer transfer gear. Should I try this one? What can it hurt? Higher speeds, less low end?

I'm hoping TqRc has both the transfer gear and diff in stock, better prices! If they can keep parts in stock, they will be my new Tower.
That TQ place, the last time i looked only had parts for that onroad car, the off road parts are the exact same as the onroad car parts catagory. off road cars don't have 20 tooth pinions and 40 tooth spurs. LOL
excuse me, 24tooth pinions and 40 tooth spurs. all the parts there are for the onroad model they don't have any of the off road parts unless you can call them and ask for offroad parts. i guess the suspension and frame parts would probably be the same, maybe a few different parts between the two.
Will the FG 48 tooth diff gear and 14 tooth tranny gear work on my truck? BiggertheBetter? Know the answer, you are my resource for all that is cloned....;)
I'm almost 99% positive it would work. I have used the FG 48 tooth with the CNR carrier on the FireHammer to replace the plastic carrier and spur with no problems. You will pay more for the FG's but, I can tell you it's an upgrade for the differential gear going to Fg the gear is wider and almost matches the thickness of the transfer gear, it also to me is also a harder metal then the FH's. I am speaking from my experience with my FH buggy and not sure but think the MT is very similar. On the FH the spur shaft is almost identical to FG and the differential is as well after looking at the MT parts they cross to the buggy in most cases. Good luck....:)
I may try it. I have tried one more time to line the gears up correctly. The funny thing is, it rolls really smoothly after I align the gears and tighten everything down. As soon as I start up and take off, it grinds horribly.

I took the engine off, made certain there wasn't something weird with the diff itself, put the engine back on and realized that the brake adapter was loose. Not just a little loose, but rotating around the shaft loose. Don't know if that was part of the problem, but I've tightened that back down as well and checked everything else.

What type of loctite do you use? I am using some duratrax blue loctite and some team associated loctite (blue). Not sure if there is something better from an automotive store or not. I've heard to stay away from the red loctite unless I want to take a blowtorch to get screws to loosen.

Thank you for the info bTb. A wider gear would be much, much better I think. I'll see what happens tomorrow and go from there after I run it. The wife would love to hear that I'm going to spend another 70 bucks on little metal things. I mean heck, what else would I want to spend 70 bucks on......dinner, a night out, diapers??? ;)

Thank God I receive all the credit card statements and pay them!
Figured out the problem with the gears.

The whole diff, including the internal gears are pretty much destroyed. See attached pics. Once you see the pics, they will pretty much explain the grinding.

Not too happy at this point. It will be awhile before I probably get the parts to fix this. I guess running on flat ground could have caused this? I don't know. The tallest jump I have hit hasn't been any more than a foot in the air. :no:

ive heard of alot of people screaming about there broken diffs with the clones and the fg cars. and i have a computer virus, its really hard to type anything it keeps stopping in the middle of the sentence. pos how does a virus get passed 5 scanners and 2 firewalls, i should burn this thing. Oh well, but yeah the diff thing is not new its on going from what ive read ive either trashed mine too or the clutch is slipping it will just free rev every once and a while.
things that screw up a diff are all the things we like to do with these cars and trucks. number one diff killer is jumping any kind of jumping, if the drive wheels are off the ground then reconnect when your on the throttle its a large shock to the diff. number two killer mostly of the innards is donuts or on power transitions from low traction to high traction surfaces such as from gravel to street, or grass to street. number 3 wheelies every one likes to do wheelies and that will screw up a diff.
only choice is to upgrade the material in the diff and transmission gears. however when upgrading you simply move the problem further down the line with each upgrade. you can do a full metal drivetrain and including wheels. and then it will start messing up the weaker metals. the weakest link will always go and there isnt much you can do besides buy spares.
According to this thread at RC(blah)U, FG part #8484 will work with the stock gears. I'm going to e-mail teamchrome as I think I have seen him post around this forum. $75 bucks for the alloy diff and then I'll just order the gear parts from and should come in at about $100 bucks. Not too bad considering Tower never has the alloy part!
The stock FG plastic housing is 95% the same as the FH's the only difference is it is tapered at the end instead of stepping down. You should have no problem installing the stock FH gears in the FG housing, that way you don't have to buy new outdrives. Funny thats exactly where mine broke causing the Dif gear to hit the chassis breaking a tooth and mashing the gears inside..:cursing: Don't feel lonely though I tore my FG down after the Hammer and found I lost one of the teeth on one of the large outdrive gears and the tooth was flowing around in the grease. Thank goodness I found it before the whole gear assemble chewed it up. Just the one gear which is sold in a pair was 35.00.:(
I'm on a string of bad luck, but the FH is back together, and so is the FG, all the parts just came in so the crate must of made it through customs on Thursday.:clown:


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I put the alloy fg diff housing & carrier in my hammer & have had no problems with it..Just make sure you use the firehammer gears & the hammer outdrives because the fg outdrives wont fit in the hammer gears..
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