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21BB Backplate & Rotor Start

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LarryA

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Just thought I'd let Roto Start uses know that you need to keep an eye on the starter housing. My screws came loose and I tightened them as soon as I noticed the problem. Yesterday the engine refused to crank, thought it was flooded at first but removed the plug and still no go. The crank turned by hand with the flywheel. Pulled the engine and found a bad one way bearing and when I cleaned and inspeced the engine I found that the backplate was cracked at the one corner screw hole. Why they designed this cover with only three corners screwed down, is beyound me. I could see that the screw holes were almost egg shaped. This came from the time the housing came loose. I'm trying a repair with JB weld and hope it holds. I also built up the other corners to give more material between the screw and the edge. This would have went un-noticed had the bearing not gone bad and eventually I would have destroyed the backplate.
I need a Picco .26! I also need the money to buy one...:confused:
 
Larry, same thing here, I have the HB Jump Start and the screws that came with it were too short so I found some laying around that were longer and Threadlocked them but they are still loose, the entire side of one of the screw holes in the backplate came off so you can see the threads right through the side of the thing. I called HB today and left a message again :mex: lazy bums never called me back, I only want to know what the actual screw size is so I can get new ones, also went to Tower to look for a new backplate, they have them for $13.99 so I guess I need a new one. I love the jump start though.

:OT: Has anyone noticed the rear end of the MT is sagging? I seem to have a set of bad rears, the back sags pretty bad.
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Problems & Fixes:
Broken Cooling Head- GH Head
Broken Fuel Tank- Turned Bolt Around-- Aluminum Gaurd
DB's fell out- HB CVD's all the way around
One Way bearing "BAD"- HPI replaced it for free
Steering Servo Crapped Out- Futaba HI Speed
Runaway:argue: - Ofna Fail Safe with radio mod.
Stock Pipe too loud- HB Aluminum Tunes
Dirty Motor- Motor Saver Air filter
Spur- Gear tore up!- Replaced with Stock from HPI
Would not Shift- Adjusted Clutch range
Sore Fingers- HB "jump-start":bow:
Wheel Flew off- New Wheel nuts All Around
Clutch Bell Bearing Flew off- Ofna 13t CB with bearings
Lots of $ for Batts.- Trinty 5 cell hump pack.
Man Am I NUTS!
 
The sagging rear is caused by the weak as springs on the shocks. Upgrade to stronger springs or better shocks, and the sag will go away (except under power...you might see a little squat in the rear when you jam on the throttle).

As for the laundry list of problems and your being nuts...I'd say long list for a "new" truck, but you are far from nuts. I'd say you are living the true meaning of this hobby...run, break, fix...repeat.
 
Originally posted by SkyMaxx
I'd say you are living the true meaning of this hobby...run,
break, fix...repeat.
Click to expand...

See sig below......
 
Anyone know the size of those screws that go through the roto and into the backplate? I need length and diameter. Also where do you guys get screws and bolts that you loose? LHS, HomeDepot? HPI? Thanks.
 
Overall, my problems so far pretty much relate to the engine area.
Basically here's what I done so far:
Replaced Roto Start (destroyed itself first day and dealer gave me new one).
Roto Start housing screws came loose and cracked backplate (fixed with JB Weld)
One Way bearing went (just bough new one but may call HPI and try to get a replacement for extra)
Installed Hot Bodies clutch and they blew apart (put factory back in)
Motor Saver air filter with external foam cover
Changed shock oil to 35W front and 40W rear.
Added preload to rear shocks until I can buy better ones.
Replaced upper arms with Golden Horizon aluminum adjstable.
Replaced body with '73 Bronco

Overall it has not been bad except for the problems around the engine. I've had to pull the engine about 4 times already. Tuning was a pain but seems to be running pretty well right now (maybe I shouldn't have said that?). I did see that I am about to now strip out a wheel. Another impeeding exspense...
Anyway, such is life with R/Cing.
All have a Safe and Happy 4th Holiday!
 
Originally posted by J. Whalen
Anyone know the size of those screws that go through the roto and into the backplate? I need length and diameter. Also where do you guys get screws and bolts that you loose? LHS, HomeDepot? HPI? Thanks.
Click to expand...
LHS, Local HARDWARE Store. I find this proves invaluable to finding nuts and bolts and not $100 for 20 stainless steel screws that your local hobby store charges.
 
Ditto on the "Hardware" store. Most times even metric machine screws are only a few cents a piece, compaire to a couple bucks for a pack of 5 or so.
 
Larry! 4 times for the motor out! how about 20 at least (lmao) I can get the screws but I would really like to know the exact size that came with the HB Jumpstart if someone could measure them.

Also looking for a NTC3 if anyone knows where too get 1 cheap or a good used. Thanks.
 
Ok, the Roto Start Instructions list the three longer screws as M2.6x12mm and the two shorter screws as M2.6x8mm. These are the factory length screws. If you want longer you need to add to the 12mm and 8mm the amount you need.
 
The screws should be the same length for the roto and jump right? I bought my jump on e-bay and the guy sent the original short screws that came out of the pull start, I called the guy and he said he would send the right ones and sent the same shorties. I found some longer ones but they screwed up the threads which got all sloppy on the backplate, so the metal fell right off of the backplate around the screwhole so I had to buy a new one I just dont want this to happen again so I wanted the exact sizes. Thanks for the help.
 
I can't remember if the Roto Start came with new screws or just used the ones from the pull start. You now have the thread size (M2.6). All you need to do is measure how long you actually need them so you purchase the correct length. You could measure over the outside of your Jump Start and the backplate then subtract the length of the screw head. Screws (machine screws and bolts) are sold by the length of the bolt from the bottom of the head to the end. Do not include the head length when figuring how long need one. Sorry, butI can't help you any more than that.
 

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