fuddy-mucker

Hi yes its a pb battery. Just done a quick check and it begins to bubble and fizz as soon as the charger is connected up. Voltage goes from 6.6 volts to over 7 when the charger is connected. Disconnecting and over a period of ten to 15 minutes the voltage steadily drops to 6.6 volts. Im wondering if a new charger might be whats needed?

Hi folks, im hoping someone could kindly help me out we were given a 4 wheeled electric quad by a friend of the family that no longer worked. Having got the multi tester on it we found that despite charging the original battery when the foot operated throttle was used the battery voltage showed 0 so... Having bought another battery excellent issue sorted. However, having started to charge the new battery after approximately 1 hour the batyery can be heard bubbling slightly. It doesnt get warm to the touch. Its an ultramax 6v 4.5ah battery.the charger is the genuine feber charger. Output is 6v 600mah. The battery is a sealed lead acid battery in the link below is the exact battery https://www.ultramax.co.uk/ultramax-np4-5-6-6v-4-5ah-20hr-as-4ah-sealed-lead-acid-rechargeable-battery.html The battery itself has only received approx 4-5 hours charge and when i first heard the bubbling, turned off the charger and disconnected the wiring connector. Tested with multimeter to find it over 7.3 volts. After 10 or so minutes this then dropped to 6.5 volts. This isnt mine but the exact same https://www.gumtree.com/p/other-outdoor-toys/kids-quad-bike-feber-shark-620-with-6-volt-charger/1328260794 Many thanks in advance

I just had quite a few problems in fairness... evwn when just running on flat grass and not even running hard. Would you be willing to sell the 28 spares you have?. That engine looks good really especially for the money too!. You say you upgrades your s28 upto an s50, what did you need to change?. At the minute im in two minds wether to stick to s28 parts (cheaper for me and would be easier). Or... upgrade everything to s50 spec, little more expensive but doubt the truck will break as easily/often. Thanks Rob

Nicelys! What a way forward. The prices here in the u.k are pretty expensive i find. Even with shipping its cheaper to come from the u.s! Thanks for info and i'll be sure to check them out fella!. Just a quick question, having seen the prices and availability of parts etc... im seriously considering a full strip down, replace every nut, screw etc for stainless as they sell them as a complete kit for the mta. And also... rebuild it back upto being an mgt8.0. Engine, box, cvds, hex's and wheels and a few little upgrades a reckon. Can anyone make a list of thibgs i'll need to convert my mta4 s28 (mgt 4.6) into an s50 (mgt 8.0). Just make sure. Thanks in advance!! Rob

Evssv, is the s28 and the mgt 4.6 the exact same?. Just looking on american ebay and wow!! Loads of spares and parts lol wish id thought about it sooner. Whats the difference between the two? I know they are the same but.... anything to be weary of? Thanks fella Rob

Hi all.... Well its been sometimes since i paid a visit to the forum. In may 2013 i bought a brand new tt mta4 s28 from js models at a good rate and despite having a few teething issues... well... constant battles i did finalky get the truck running well. However, on the ladt outting ( septber 2013) i took the truck out and despite the weather being really warm i ventured on to the grass with the truck and unknowingly to me at the time further down the field the truck had become wet due to damp grass. The spray had got past the backingplate and made its way into the engine. ( the grass was also quite long). The engine cut out and took a good 15-20 minutes before it would fire back up. Pullstart and rotostart used. Then once running again i chose to let it idle for a few mins to dry out and then gave it a few passes on tarmac and suddenly the gearbox appeared to die. So... that was the end of it. It was brought home, put on top of the unit and left until my next day available to muck around with it. 3-4 days later despite using aro after every use, the engine had locked solid!! Bearing in mind the truck was only 5 months old. I stripped the engine to find the internals were seized solid with rust. I managed to free it all off but the crankshaft bearing is nothcy and the sleeve is marked and scored. Engines is only fot for the bin i think as the owb was also seized and now theres a few bits missing too from storage. I rebuilt the gearbox but found it a tad complicated due to having a reverse gear but... i believe i got there in the end but havent tried it out. For the past two years it has sat in my parents loft space. Im now in two mind as to what to do, it has got: Copper spring upgrade all round x8. Dual tank mod running in series and works Byron big air filter Rebuilt gearbox ( believe it should work) A few other bits iirc. But with a dead engine, unknown if the gearbox.will work properly or not Various screws and other bits missing i.e... clutch springs, carb clamp, all the slipper clutch parts but to name a few. Do i give up and bin it ( a waste!) Or... could one or a few of you guys help?. Ideally i would like to buy a brand new engine, seal.and start again lol. But buy a 2nd hand truck to use as spares to keep costs low ideally. As ive also just moved out but.. this hobby is addictive lol!. So... what would you do? Also do you have an mta4 s28 you would be willing to sell for spares? Im in the u.k, in west yorkshire. Id much sooner repair the truck without it crippling me.financially as.. truth be told, i bought truck from inheritence i got my from grandfather. I bought it with the money because my grandad used to fly model aircrafts and occasionally used to have a go with one of my rc cars and i biught the truck really... to be reminded of the times we had and the time we spent tinkering and fixing together. Learning new things. Such as.. how to strip the hobbypro mutilator 6 carb without loosing the carb settings despite removing the jets.and how to re-use gaskets without the use of sealant etc etc.. I dont want this to sound like a sob story however this truck does mean something to me but i also now have responsibilties financially and in the back of my mind.. know that if the truck is in bits and never runs again.. it wont matter because i still have it but...would be nkce to see it running again. Sorry if anyone finds this hard to read im using my phone due to no broadband at the minute having just moved out . Thanks in advance and sorry for the ramble lol Rob

Thanks guys, Ive seen the complete engine on ebay at 104 quid. That would be the easiest option bar none as all i would have to do is strip n seal it with hylomar engine sealent and reassemble and tune and break in. Having thought about it, this would probably be the best option as my current cylinder line has signs of scoring too. I have looked around for that bug ball bearing race for the crankshaft inside the crankcasing but cant find where i can buy just that bearing from. Although... i have found this! http://www.robinsonracing.com/catalog/gt.html A steel spur gear for the s28!! No more plastic breaking lol! Rc10 gt machine steel spur with clutch bell. Should fit shouldnt it? Thanks rob

Hi everyone, its been a while since my last visit due to financial and housing changes etc. My last post was about 5-6 months ago when my 6 month old mta4 S28's engine had seized. I managed to "un-seize" the engine due to rust on the lower internal parts it was subsequently stripped and cleaned and then re-assembled. now it turns over with lots of compression and seems okay. Except on one part of the rotation of the engine it appear to "stick" as if there is rust in the bigger main ball bearing race in the bottom of the crank case. so having googled all over the place i can't find this standalone bearing so... fear my engine is duff. theres also wear to the piston liner. can anyone point me in the right direction for a new s28 engine (not bothered for the s50 engine as I just want to get it running again correctly) and a screw set for the whole truck? if anyone has a spare "known to be working in good condition engine" I may well be interested pro 28bdr however. Thanks in advance Rob

Hi all... after a few months away, a house move and working long hours i may in the next month or so be able to allow some time to get the s28 back up and running. My engine had seized and was freed off however it is now grating and notching when turned over by the fly wheel. Because its also in bits im going to take this opportunity to completely sort it out and make it more reliable in the process.. Heres the plan.. New engine ( possibly s50 engine brand new). Strip and seal with hylomar sealent. S50 gearbox ( what else do i need ? Diffs? Shafts? Hex changes? ) also... im wanting metal wheels as im sick of the metal hex nuts rounding the plastic wheels off. I have managed to sort this by using lockthread and two wheel nuts per wheel. But still a weak point ( where can you buy metal wheels? Im going to take my time with it and really get it sorted. So when it goes out for the first time its just breaking in the new engine and tuning. Afterwards as always minor tuning tweaks and thats it.. i wont be running the mta4 for as long as i used to i.e being out all day with it, fixing and breaking stuff, just thinking of taking it out for half an hour or so after that it can just sit in the house lol. So.. what else do i need to conver the s28 into an s50? Thanks Rob

Ive always let the engine sit at idle for 30 seconds or around that figure then shut off using the exhaust drain the fuel outta the tank and pop the fuel tube off and give the primer bulb a couple of squeezes so the system is purged of fuel. Im hoping to try and start it up tomorrow ( possibly) so wish me luck!!). I've put too mych money into this and will lose a lot if i sold as i highly doubt i'd get around the

Okay... appologies for the sounding off in this thread. Progress! The engine which was completely seized has now been sorted! it was stuck completely!! a pan of boiling hot water and the engine was dropped into it, left to boil the engine in the pan for 5 mins, and then placed straight into the freezer! The heat causing different metals within the engine expand at different rates, same as when they freeze when they contract they do so at different rates. This resulted in the sleeve coming out very easy! I was then able to disconnect the conrod from the crank shaft so the piston was the removed the crankshaft then came out. Done! . The internall ball bearibg which the crankshaft sits on was the only thing left in. The crankshaft and a few other bits were attacked with a wire brush to remove loose rust the crankshaft centre bearing was also attacked with a wire brush to remove loose rust. The entire engine was blasted with anti rust silicone spray to help shift any last bits and also prevent rust forming further. The engine components were liberarly coated wuth aro oil and put back together. It now rotates freely wuth good compression and hasnt seized again while being stood. I am yet to run the engine as i need the metal shim gasket for the heatsink and also a owb for the dual start as nor the pull or drill rotates the engine but turns over fine with the flywheel. The gearbox needs two screws securing inside and a good spray of white grease on tge metal gears and sealing and it should be good. My approach to unlocking the engine may seem ridiculous but hell... it worked!! I only hope after a run the slight notchyness when its a bdc goes ( the position the engine was in when it seized so clearly has caused a lip on the crankshaft bearing. But hope this goes when its been run for a bit. Rob

Whats the point in manufacturers using customers as developers?.. I mean c'mon.. you dont buy a car from bmw or ford for that matter and have to rebuild it every time you use it :/. Why not build them fit for the purpose in the first place?

Speedods you have pm too, btw also has byrons gen 2 dual race intakr air filter. Byrons gen 2 race fuel at 25%.

Well lets face it... with the crap arse build quality it could probably summon rain in the desert purposely to seize the damn engine! No it was a hot dry day, im not a fan of standing around in the rain lol. Meh, ive owned classic cars ( 1:1 scale!) And never had so much shi1... al probs get back into classic cars after this lark! So aint worth the hassle Btw nice spitfire avatar previous dolly 1300 owner

Pistonhead and sleeve