help

[rcdave]

Finally finished building the car yesterday, and decided to take it out on the street for a quick spin.

When trying it on the street I hit a low curb trying to jump it into my driveway, and the steering came apart. The one side came out of the steel cross brace. Looked back over the instructions thinking I forgot to put a screw in the top to stop it from coming loose, but there is not one. Put a washer between the steel cross piece and the black pivot that goes into the cross piece on both ends. Is this enough to stop it from coming out again??

Second, the car ran sweet but the diffs sounded loose as it took a bit of winding out before it got to speed and you could hear it slipping.

Took car inside and tightened the diffs up but testing it on my workbench it still is slipping. Tightened the slipper clutch a little bit and it is still slipping somewhere.

I am getting really frustrated, after taking so long to put together and now not being able to run it, I am just thinking of tossing against a wall now.

Any help would be appreciated.

Thanks in advance, Rcdave.

[Northy]

Dave, which part of the steering jumped out? I don't understand. Can you take a picture? Sure I can help.

What grease did you use in the diffs?

G

[rcdave]

Don't have a camera handy, but I did look the part numbers up in the manual.

The black part # X9TX came out of the steel steering rod (part # X12BN).
There is nothing keeping part # X9TX from coming out of the steering rod. I would think that another screw should go into the top of part X9TX as well as the bottom.

As for diff grease not sure what I used as I could not find my associated grease. I have many many diffs before and never had this problem before. It was proper grease just for diffs.

Thanks.

I am hoping, that it is not the prop shaft turning in the pieces that were glued. Not sure how to check this out.

[Cooper]

take some pliers or 2 thin screwdrivers to lock your gears and try to turn the gear, it shouldn't

don't tighten your slipper to much, your slipper is made for slipping, diffs aren't
Have you used silicon grease for the 'big balls' and thrust grease (or whatever it is called) for the trust bearing? tightened it enough?

[pro4nut]

You don't need a screw in the top of the link because if you put one in there it will stop you getting full lock as the head of the screw will hit the chassis.
Do you have a carbon steering link or the stainless one?
If i am being honest with you it will not come out with the steel link provided you assemble it as below,

from the bottom
1. 2.5mm button head screw
2. 3mm washer
3. steering link
4.additional washer (3mm shims) to remove slop
5. ptfe spacer

the spacer locates in the steering linkage (help with the right part name coop) without a screw, i have had it pop out twice but only when running the old carbon link.

To set the diffs once you have tightened them put a small drop of superglue onto the end of the screw using a small proddy thing (tech speak again.....sorry coop) into the threaded difff half but be very careful

to check diffs are set correctly put them in a diff setting tool (tc3 or pro4 or sd will fit) and try to rotate the crown gear. you should not be able to turn it with your hands, check page 14 of the pro4 manual downloadable from hpiracing.com, this also shows how to check the diffs as cooper describes using 2 thin screw drivers.

To adjust in the car hold three wheels, 2 between your knees and one with your left hand and rotate the other wheel with your right hand this should show you how much slip the diffs have. the x10 diffs are very smooth and it is very easy to set them loose if you have ever built a losi diff (which sound like a bag of rusty nails being ground into a blackboard with an angle grinder)

to set tension while in the car insert a 1.5mm hex driver into the diff screw and hold still, then rotate the opposite wheel in 1/8 of a turn increments until correct, (thats how us touring car drivers do it as i adjust diff tension evry run as the grip comes up)

Hope that helps my fore finger hurts now.

[rcdave]

thanks for the tips, will try to fix it on thursday.

[bigboss]

well put Pro4, saved me a lot of typing,thanks.

[rcdave]

assembled steering almost the same as you suggested, but did not put the washer between the bottom of the screw and the steel steering link(your step 2). It poped off after the first hit, so I installed another washer to make 2 on one side that poped off and one on the other, and of course the side with only one washer poped out later.

took the diffs out of the car, tighened them up, put a dab of glue on them and put them back. Tighened up the slipper as well. After half a pack something is slipping big time.

finally gave up and packed up and went home, after the steering poped off for the second time, by the way only very small taps into the o pipe, no major crashes.

I know a couple of guys that own them and hopefully I can get one of them to take a good look at my car and fix it up for me.

I know the car has potential but I just have to get it to work first.

[pro4nut]

I have to say mate, that if you had done exactely as i said you would not have the problems you have had. The final set of the diffs should always be done in the car, i believe that you have still not set them tightly enough, i had this problem the very first time i ran the car as i did not set them tightly enough. The point is once the glue is in and has tried DO NOT ADJUST THEM AGAIN, if you do adjust them you will break the glue bond and they will work loose. It is very easy to set them loose as there is no compression spring in the diffso you have nothing offering resistance to your tigtening when you turn the screw.

Silly question but have you got the diffs in the right way round?

I hit a pipe at full chat yesterday, broke the wishbone (only on the front edge was still mounted at the rear) and still kept the car going for another 3 minutes as the steering link did not pop out.

[chris burgess]

Wayne - I thought the same as you, about the diffs being in the wrong way when I read dave's last post......

I am amazed at how much trouble you are having with the differential and the steering. The diff in mine has not been touched since I built it, and is as smooth now as it ever was. So, I would suggest that you strip the diff down, soak it all in white spirits or similar, to clean and degrease, then rebuild it as per the instructions posted in this thread.

And your steering - you do have the stainless link and not the carbon link don't you? The carbon link was a pain, but the stainless one is spot on. As you have found out, the stainless link, like the carbon one, basically "floats" on the chassis, and if built as per instruction, is not secured by a screw. BUT because of the tolerance in the construction, this is not usually an issue. But again, if you follow the advice given to the letter, and attach the links with a screw and washer it should never ever come adrift.

Let us know how you get on - and if you can, post some pictures of your car as it is now.

Where in the world are you by the way?

[YoKoMo-MX4]

One other thing to check is that you have the M3 washer installed between the lower steering bellcrank bearing and the steering arms. See page 15 of the manual ... I missed this the first few times around on my X10.

'nuff said,
MX4

[rcdave]

Thanks again guys, I will look into what way I have the diffs in.
I do have the M3 washer the way it should be on pg 15.

I think I may know why the steering keeps poping out, I think that when I was widening the hole for the steering rod to come out, I may have widened the holes that the steel steering rod comes out of the chassis. If I made the hole to big, maybe the rod has too much room to move up and down.

Never built a car before that only uses pressure to hold the steering rod in.
I have been building and racing electric cars buggies and trucks etc for many many years. I have built Yokomo, Losi, Associated, Tamiya, X Ray, Kyosho, HPI and never had this many problems before.

[pro4nut]

The hole for the link did not need to be made any wider, you may need a new chassis.
The quick fix would be a large stack of spacing washers, again under the ptfe bushing but you will have a lot of slop, get a longer screw and drop superglue down the inside of the bushing before you tighten the screw fully. I actaully throw away the bushings after each race meeting as they seem to act as a servo saver when you 'drive like you stole it'

With diffs the tension screw head will be at the left rear side of the car and the front right on all cars except a losi xxxs or xxx4 where the screw heads are always both on the motor side of the car. If you remember this you will never go far wrong.

"have built Yokomo, Losi, Associated, Tamiya, X Ray, Kyosho, HPI and never had this many problems before. "

i have also built cars by these manufacturers and i would say that problems assembly can happen with any car, it is always critical to 'dry' fit everthing before completing a stage and working ahead of your position in the manual. I have been a scale modeller for many years sometimes spending months working on a single model.

measure twice screw it up once

[rcdave]

Okay this may sound stupid but just for clarification.
As I look at the car from the back, what side of the car should the diff adjust screw be on?

After seeing another predator, I am sure that when I was building the chassis I made the holes that the steering link goes through bigger because it looked like they would bind.

Guess I should have read the whole manual first. Hopefully I can fix it without having to buy a whole new chassis. I am going to put a screw in from the top and put a nut on the bottom. I may have to cut some of the chassis away to clearance the top of the screw head, but cheaper than buying a new chassis.

Thanks for all of your input so far I can't wait to get it going properly.

[pro4nut]

Looking from the REAR the screw should be on the LEFT for the REAR diff
and on the RIGHT for the FRONT diff

good luck and feel free to post pictures or email if you need help