Notices
Redcat Racing Support Moderated Support Forum for all Redcat Racing Cars, Trucks & Buggies

How "notchy" should my diffs be?

Old 01-04-2008, 10:48 PM
  #1  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default How "notchy" should my diffs be?

I'm going bashing for the first time since breaking in my Hurricane XP this weekend, weather is supposed to be amazing here...

I'm doing a prep on the car because I really don't want it to break due to my stupidity...

When I push my car it seems very "notchy" in the diffs. I mean it almost seems to lock for a split second. seems to be coming from the center diff.

If I set the car on the rear wheels and hold the fronts it seems to roll ok but somewhat clicky, same with the front.

But on all 4 it's notchy.





I took out the motor, front diff and suspension, and electronics last time I ran the car to clean it. I did crash but only hit the front wheel breaking it and the control arms. everything else seems fine. I did not adjust the mesh on the gears took out the motor with the 4 Phillips head screws so the adjustment did not change.

also the car only has 7 tanks through it.

What should I do? Will it be ok to run?

bear with me... I'm new to the RC scene. Although I am an auto tech so be as technical as you want...


One more thing, Is there special oil for the diffs or can you use shock oil? They're both silicone oils right?

Please help, I told my brother I'd take him out to drive the car for his B-day...


Sorry for the rant
Old 01-04-2008, 11:06 PM
  #2  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

I took the center diff out and it seems fine... I think the noise is coming from the CB and spur gear. could it be a mesh problem? perhaps too tight?

Any help would be great.

Thanks in advance
Old 01-04-2008, 11:19 PM
  #3  
twomanytoys
Senior Member
 
Join Date: Jan 2007
Location: , PA
Posts: 5,382
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Thats what it sounds like. Mesh between the spur and bell. It should feel loose. If you hold the spur then just turn the bell back and forth you should have a tiny bit of play. If you dont have any play then its too tight and it will tear the gears up and overheat the bell.
Old 01-04-2008, 11:26 PM
  #4  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

There is a tiny bit of play like you said. maybe too much?

the gears have a slightly polished face to them.

I would say I have about 1mm of play while holding the spur gear.
Old 01-04-2008, 11:37 PM
  #5  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

I decided to take the engine out of the equation... So I took it out...

Still makes the same noise... so its not gear mesh.

Am I chasing a ghost? are the diffs really that loud?

[:@][:@][:@]
Old 01-04-2008, 11:38 PM
  #6  
twomanytoys
Senior Member
 
Join Date: Jan 2007
Location: , PA
Posts: 5,382
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

The play should be about the thickness of a piece of paper maybe 2 pieces max. They will have a polished look to them.
Old 01-04-2008, 11:39 PM
  #7  
twomanytoys
Senior Member
 
Join Date: Jan 2007
Location: , PA
Posts: 5,382
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

it will make some noise no matter what. Once you get more run time it will get quiter and also put fluid in the diffs not grease.
Old 01-04-2008, 11:49 PM
  #8  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Is there diff specific oil? I know there are different weights, But is silicone shock oil the same stuff?

I have some 45 weight shock oil I can use if it is...




BTW. I think figured the noise out...

I had the servo and brake links set to tight on the brakes. caused a slip----stop scenario...

and the noise I'm hearing seems to be the brake pads and rotors rattling. Made kind of a jingle noise.

I starting to think perfectionists and RC cars are a bad combo...


[&o]
Old 01-05-2008, 08:24 AM
  #9  
ehroof
 
Join Date: Feb 2006
Location: howard beach, NY
Posts: 16,490
Likes: 0
Received 1 Like on 1 Post
Default RE: How "notchy" should my diffs be?

diff oil and shock oil are different, the sound you hear is normal and will probably go away the more you run it so dont worry. perfection will save you some $ in the long run.
Old 01-05-2008, 12:09 PM
  #10  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Thanks guys.

It just seems weird to me.

If i put my index finger on the rear wing and slowly push forward the car seems to lock up then roll lock up then roll etc... its not the brakes or the engine. so I'd have to say it is in the diffs, something is jamming.

I could swear it rolled better when new. oh well whats the worst that could happen?
I strip the diff gears...
Old 01-05-2008, 12:21 PM
  #11  
ehroof
 
Join Date: Feb 2006
Location: howard beach, NY
Posts: 16,490
Likes: 0
Received 1 Like on 1 Post
Default RE: How "notchy" should my diffs be?

yeah, give it a run and keep your eyes on it. I just realized you took the engine out, does it seem to be more from the front or rear, maybe take the front and rear drive shafts out and give it a check, see if one is making more noise or hanging up.
Old 01-05-2008, 02:10 PM
  #12  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

I pretty much stripped it down to just the electronics, front and rear diffs. pulled both drive shaft yada yada yada...

I just ran 3 tanks through it an it seems fine. problem is I have so much fun with it it makes me want another one. Maybe a kyosho next time.

I really want a kit so I can make sure everything is just how I want it from the get go. Just bought an RTR to get into the hobby and learn about nitro cars.




I made a jump on the last run and hit it a little wrong. it did some flips through the air and broke one of the cheap weak wheels the put on these cars. I have sportechs solid wheels on the front right now cause I broke one last time too. going to buy another set. at 18 bucks pre mounted it was hard to beat. Oh also bent the shock tower a little. I may make some out of stainless steel with E-machineshop. what do you think?
Old 01-05-2008, 02:19 PM
  #13  
ehroof
 
Join Date: Feb 2006
Location: howard beach, NY
Posts: 16,490
Likes: 0
Received 1 Like on 1 Post
Default RE: How "notchy" should my diffs be?

or get the upgraded one they make, thicker aluminum and lighter than the stainless. Also, check out suprasales on ebay, i get alot of my tire and rims sets from him, he has from 1/8 to 1/10, buggy, truck, truggy and onroad foams.
Old 01-05-2008, 02:24 PM
  #14  
Macanan
Senior Member
 
Macanan's Avatar
 
Join Date: Oct 2007
Location: New Tazewell, TN
Posts: 1,348
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Redcat has the rear shock tower on sale right now for your Hurricane XP


http://www.redcatracing.com/itemdeta...?partno=81603B

And if you dont want to spend to much money right now on the front tower, what I would do is buy another stock front tower and add it to the one on it you have now for double the strength. Which the front stock tower is on sale as well.

http://www.redcatracing.com/itemdeta...p?partno=81007
Old 01-05-2008, 02:57 PM
  #15  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Yeah I know about the upgraded towers. I just don't think the aluminum redcat uses is all that strong. If soft damp dirt bends them, I'm sure some hard pack would bent the upgraded ones too.

If I used stainless I could keep it 3mm and be stronger than the aluminum. doubt it would be very heavy.

anyone have the upgraded towers and crash tested them let me know...
Old 01-05-2008, 08:45 PM
  #16  
ehroof
 
Join Date: Feb 2006
Location: howard beach, NY
Posts: 16,490
Likes: 0
Received 1 Like on 1 Post
Default RE: How "notchy" should my diffs be?

one of my buddy's has them on his tsunami and they are fine, no movement or bending at all. they are much thicker than the stock ones.
Old 01-05-2008, 09:27 PM
  #17  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Well I think there is a definite problem here.

I think the gears in the center diff are all crunched up

The front wheels are now pretty hard to turn now with an ever more present crunchy noise.

bad news will follow[&o]

I don't know what else it could be so I'm going to rip into it. I just bought a gallon of gas that is now going to sit on the shelf while the cane is down once more. [&o]

poop
Old 01-05-2008, 09:49 PM
  #18  
Chubbysdad
Senior Member
My Feedback: (1)
 
Join Date: Jun 2005
Location: Clermont, FL
Posts: 2,824
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

take the diffs apart. We have been noticing that the pinion needs to be shimmed alittle because they are not meshing right. On a few you can move the pinion alittle therefore, it will not always mesh with the diff gear. I'm not saying this is your problem but worth a look.
Old 01-05-2008, 09:49 PM
  #19  
Macanan
Senior Member
 
Macanan's Avatar
 
Join Date: Oct 2007
Location: New Tazewell, TN
Posts: 1,348
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

Check your drive cups, thats what your dog bones goes in, mine was making a crunching noise and locked up a second or 2, only to find out that the dog bones had cut into the drive cups. Thats what was causing my crunching noise.
Attached Thumbnails Click image for larger version

Name:	Ca82928.jpg
Views:	33
Size:	31.5 KB
ID:	843299  
Old 01-05-2008, 10:05 PM
  #20  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

ok took out the center diff its fine. if I hold one side and turn the other its butter smooth.

Now the front and rear same deal.

The problem lies with the outer ring gear and the gear for the front driveshaft cup. thats where all the binding is on both diffs.

can I pack the diff boxes with some nice redline grease? there is a little bit on there but could I fill the whole box up? or do you think that would be a bad idea?
Old 01-05-2008, 10:08 PM
  #21  
ehroof
 
Join Date: Feb 2006
Location: howard beach, NY
Posts: 16,490
Likes: 0
Received 1 Like on 1 Post
Default RE: How "notchy" should my diffs be?

i wouldnt pack it in but you can liberally apply it.
Old 01-05-2008, 10:10 PM
  #22  
Chubbysdad
Senior Member
My Feedback: (1)
 
Join Date: Jun 2005
Location: Clermont, FL
Posts: 2,824
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

thats what I am talking about. Is there any play in the pinion?
Old 01-05-2008, 10:13 PM
  #23  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

is that shimmed too?

I took the whole front suspension off as a unit, looks like some kind of mechanical crab lol with the shocks and control arms hangin there...

why do you think if I packed it with a thick grease would be bad? maybe too much resistance?
Old 01-05-2008, 10:14 PM
  #24  
smoothoperator
Junior Member
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2007
Location: , NJ
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

no no play at all, it feels very tight... it binds when I turn that drive cup.

goes, click click click very notchy...
Old 01-05-2008, 10:16 PM
  #25  
Chubbysdad
Senior Member
My Feedback: (1)
 
Join Date: Jun 2005
Location: Clermont, FL
Posts: 2,824
Likes: 0
Received 0 Likes on 0 Posts
Default RE: How "notchy" should my diffs be?

of course. You need to shim them to make the correct mesh. They are not always perfect from the factory. Most people just deal with it. Here this is what is supposed to go in the diff case. http://www.clermontmotorsports.com/s...iff-oil/Detail

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.