Drewie Posted January 7, 2010 Share Posted January 7, 2010 (edited) UPDATED - Post #6 Hi folks After about a year of being tucked away behind my scuba gear, I finally decided I would get around to fixing my HoBao Dominator. The pull start has had it (spring inside apprears to have snapped!). I shelved the truck but never ordered a new one. As is often the case, a week turned into a month, a month into a year etc. I'm going to invest in an electric starter (any tips?). Also is there anything I need to be aware of before trying to start it up again? When I shelved it, I drained all the fuel out of it (and binned the remainder of the bottle of fuel I had, gonna get some fresh stuff) and used after run oil. Whilst taking the old pull start off, I checked the engine and it still turns over freely and I could feel puffs of air coming out of the exhaust. Here's a couple of pics Cheers Drew Edited December 28, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
dewis93 Posted January 8, 2010 Share Posted January 8, 2010 id either fix the pull start or get a new one m8, less expensive obv. Quote Link to comment Share on other sites More sharing options...
jony nitro Posted January 8, 2010 Share Posted January 8, 2010 pullstarts are Quote Link to comment Share on other sites More sharing options...
Beddo Posted January 8, 2010 Share Posted January 8, 2010 If you really want to go electric start, you can get a rotostart backplate for the Mach .28 and an HPI rotostarter from eBay for about 1 Quote Link to comment Share on other sites More sharing options...
Drewie Posted January 8, 2010 Author Share Posted January 8, 2010 I've already removed the batteries from the Rx pack (4XAA's), got a new glow plug and the needles are reset... Cheers. Wasn't sure if there was anything else that may need to be taken into consideration after such a long time of standing. As for the starter, if I'm brutally honest, I'd rather spend a extra couple of quid now for an electro starter and make my life that little bit easier in the long run. Just wondered if some are to be avoided etc I'll keep you updated on any progress I make. Cheers Drew Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 20, 2014 Author Share Posted July 20, 2014 (edited) Well this is embarrassing! I never did get around to fixing the Dominator. Here we are 5 years on from when it last ran and it has finally made its way out of the loft. Given that I now have a free summer ahead of me and some fresh winnings from the horses burning a hole in my pocket, it's time I got this lumbering beast running again. Here's the situation as it stands: I never did bother upgrading the starter. I do have a replacement pull start, but no starter shaft (evidently I binned it with the broken pull start not realising it was a separate entity.) A new shaft is will be ordered soon. I have fresh fuel and new glow-plugs. New batteries all round (currently AAs, but tempted to upgrade to a 6v hump pack in the receiver) and all the servos do what they should. I'll order a new glow starter+ charger as the other one has been sat for around 5 years and for the sake of 11quid, it's not worth betting on the old one still being useable. New fuel lines and fuel filter are on the shopping list too, along with some air filter oil (might also replace the air filter too while I'm at it). There was a couple of bolts missing, noticeably the grub screw which holds the shaft that pulls the brakes on was missing. This is now replaced, along with a half a dozen other miscellaneous bolts. I think that's about it. Other than that it's just general house keeping. I've stripped most of the larger bits off to get in and under them for thorough cleaning. The engine turns freely by hand although there is a very small amount of notchiness at TDC, not sure if this is cause for concern. It's not enough to jam at TDC, or even to make it significantly more difficult to turn past TDC, but there is definitely a little notchiness there. The engine was barely run in when it was shelved, so perhaps it's the newness still showing through, almost like the piston is ever so slightly catching on the liner. A small dose of after-run oil did ease it noticeably. If it does cause issue, I'll take it apart and look closer at the piston/liner/con-rod. P.S. Anybody else about in Norfolk? Edited July 20, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 22, 2014 Author Share Posted July 22, 2014 Well it lives! Fired up a treat once it was primed. I had to pop out, but came back 4 hours later and it fired up first pull, which is promising. I'm going to re do the run in process just to make sure it's okay after all that time collecting dust, which I will do tomorrow (it's too late in the evening to be running several tanks through it tonight). After that it'll be a case of tuning it up and heading off somewhere to have a bit of fun. Probably Rashes Green Industrial Estate after hours so I don't bother anyone. Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 23, 2014 Author Share Posted July 23, 2014 (edited) Managed to run through two full tanks at tickover this afternoon. At first it would only run with the ignitor attached. It was puffing out a good bit of smoke and spitting little globs of oil out of the exhaust. Figured that it was running too rich. Adjusted the mix a little, leaning it off 1/8th of a turn at a time. Eventually it started running on it's own. I set the tickover at a nice steady rate, it cut out once or twice during each tank, which coupled with the amount of smoke suggests it's still running rich. I figured that's fine given that I'm running it in again. Towards the end of the second tank I tried revving it up gently, but when it got to a 1/4 throttle, it stalled out. Again, given that the amount of blue smoke pouring out increased massively when trying to rev up, I'm hazarding a guess that it's running super rich. I'll take it out tomorrow and try leaning it off little by little until I can get it running at 1/2 throttle for a couple of tanks. Then all that remains it to tune it proper and hopefully fun times will ensue. Edited July 23, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
Nitroholic Posted July 23, 2014 Share Posted July 23, 2014 Sounds like it's survived it's hibernation in good order Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 23, 2014 Author Share Posted July 23, 2014 (edited) Yeah seems to have faired quite well, I was quite surprised when it barked into life, and even more so when it was running this aft. Obviously it's not been tested fully yet, there's still some way to go to get it running around smoothly and reliably, but the initial signs are promising. I guess making sure that it was properly prepped for its long slumber has paid dividends (drained of fuel, good dose of after run oil etc) One thing I had forgotten though is just how much gunk and stuff that goes everywhere when dealing with nitro cars. So far I've left several dirty great oil stains on the patio, managed to coat most of my clothing in the smell of burnt nitro fuel, there's grubby fingerprints throughout the house and when I was tinkering last night I tipped the truck up and spilt fuel on the living room carpet. Thankfully my wife is very very understanding and sees the comedy in my actions (at least for now anyway). Edited July 23, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 25, 2014 Author Share Posted July 25, 2014 (edited) What a day. After running two tanks through at tickover the other day, today I ran another 3 tanks through at half throttle. It was very easy to not get carried away as the engine bogged and died at anything more than that. Once the third tank had been drained, I decided to set about getting it to run properly. Having already made sure it was set to factory settings, I thought it would be a simple case of tuning as per pretty much every guide out there on the internet. How wrong was I. No matter what I did, the thing bogged and cut out at anything more that 1/4-1/2 throttle. I couldn't decide if LSN was too lean, the HSN was too rich or that the glow plug was baulked. No matter what I did, it just wouldn't run right. Of course, the advantage of all this jiggery pokery was that it got another full tank of fuel through at less than 1/2 throttle. Definitely run in well! I decided enough was enough. The only way to figure out whether it was running too rich/lean was to take it to the extreme and work back. So I leaned off the HSN half turn at a time until it showed signs it was too lean. Once I got there, it was back a full turn to make sure it was definitely rich again. Then the same treatment for the LSN. The result was that I was finally able to get more and more of the throttle applied until eventually I was able to pin the throttle wide open from tickover and it not stall. Excellent. Off to the park we go. Oh and I bunged in a new glow plug incase it had gotten fouled up during all the tuning frivolities. Took it down the park for a little more tuning. I ran it gentle at first as this was the first time it'd been opened up properly in well over 5 years. It was a little boggy and certainly didn't want to go full throttle at first, occasionally stalling when setting off from idle. A few tweaks here and there (1/8th of a turn at a time) and it began to fly. Whilst I didn't get it running completely smoothly, towards the end of the session there was a definite pick up of the engine note as it got to wide open throttle, almost like it was changing up a gear, so I took this to mean it was finally starting to run as it should. I didn't get it running 100% perfect though, as I ran out of fuel (damn these things are fun. I burned through 3 tanks in what felt like not time!). But it's all starting to look very promising. I'm ordering some more fuel tonight and some spare glow plugs whilst I'm at it, so next week I should hopefully get it running sweet. Here's a video from mid way though the session. Listen out for my wife yelping in fear around the 44 seconds mark. Around the 1:04 mark you hear the revs drop as it's getting towards WOT. I ironed that issue out. You'll also note at the start of the video I set off very gently. On the last tank of the session (unfortunately not on video) I was able to pin it full throttle from standstill and the little truck flew without hesitation. The brakes are pretty fierce too, with stoppies occurring a couple of times! (again though, not on the video). Oh and by the by, the toddler and child being chased by the truck belong to me. I wasn't out scaring other people's children and giving the RC scene a bad name Edited July 25, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 26, 2014 Author Share Posted July 26, 2014 Interesting development... Whilst rummaging around, I turned up some HPI R4 glow plugs (med/cold). Decided to give it a go and see how the truck responds. It was an absolute revelation. More responsive, less bogging and absolutely no stalling. I only had a couple of tanks worth of fuel left, so it wasn't worth heading out anywhere to give it a proper run and try tuning it a bit more, I was merely running it around in circles in my postage stamp sized garden, but it was staggering how much better behaved the engine was. It might be an unfair test as the OS8 that was in there yesterday did have to put up with a bit of rich running whilst I was trying to get it close to something resembling a reasonable state of tune, so it might've gotten a bit fouled up, which may explain the hesitancy in the engine response I was unable to eradicate. But given how well it responded to the HPI plug, I'm tempted to shell out the extra and stock up on those regardless. This is getting both addictive and expensive. Quote Link to comment Share on other sites More sharing options...
Drewie Posted July 30, 2014 Author Share Posted July 30, 2014 (edited) Hmmm... After a bit of impromptu streamlining (i.e rolling the car and snapping all 4 plastic "lights" off the top of the car), I noticed quite a bit of fuel leaked out. I inspected the lid of the tank and there's no o-ring in there. Looked in the box I keep the truck in and there was a thin o-ring the exact diameter of the mouth of the fuel tank, only it has snapped. It may also explain the sudden boggyness that has occurred. Having browsed around, I noticed that quite a few different models have a complex arrangement that allows adjustment of the o-ring. Mine has never had this. I'm guessing the o-ring on mine just sits inside the lid. I'm also guessing that any o-ring of the correct size will do, provided it is made of such a material that does not get eaten by the fuel. Anyone able to offer a bit more insight into this? This is the tank, Brand new'un: http://www.ebay.co.uk/itm/OFNA-Fuel-Tank-Monster-Pirate-OFN18047-/221485518611?pt=UK_ToysGames_RadioControlled_JN&hash=item339190cf13 Edited July 30, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
Drewie Posted August 6, 2014 Author Share Posted August 6, 2014 Well, how's that for sods law eh? I went down the local DIY shop and found some O-rings at a few pence a pop that fit nicely on the lid and create a good seal... Which sorts that problem out. Had every intention of tuning it today or tomorrow, and... It rains, and rains, and rains some more. Oh well. Apologies this thread has become a waffling wall for me. Feel free to offer any comments or suggestions (such as "get a monster truck where you don't have to remove the shell every time you have to start it"). Cheers all Quote Link to comment Share on other sites More sharing options...
Drewie Posted December 28, 2014 Author Share Posted December 28, 2014 Evening folks, me again... I've decided my little truck is showing too many signs of old age. Whilst there doesn't appear to be an rust or corrosion, a few bits and pieces appear to be getting tired. Namely the servos. So I'm going to replace the Hobao H-101 and H-102 (throttle & steering respectively) with Savox SW0230MG and SW0231MG. On top of that, I'll finally get around to fitting a hump pack (probably HPI Plazma 6v 1600mah) as well as fitting a failsafe. The idea is that it should be more responsive. Also, those servos will be the first steps towards making the electricals water tight, so I don't have to worry too much when running though wet grass etc. I'll be stripping the truck down again tonight. It's gotten a bit grubby, and in my haste to get it running today, I started adjusting the HSN and LSN willy nilly, not realising that the cold weather was preventing it starting/running. Consequently, I've lost track of what I've done. So I'll also be setting it back to factory spec for a full retune. I'm also considering switching fuels at some point. At present I'm using the optifuel 20% rtr, which is great, but I've not been able to fully eradicate low rev sluggishness. I had it at a stage over summer where it only had a slight hesitancy, but if there's any sort of load on the engine (slight incline etc) it almost felt like it was struggling to take off. It also felt like there was more in that engine than I was getting once it was moving. It's not exactly slow, but it feels like the engine has more to give. I'd like to get it to a point where she starts to fly the second the throttle is opened up. In my mind, 25% seems like the most logical way to get this. I'll most likely stick with the optifuel rtr stuff, the engine held its tune really well over summer with this stuff, it never struggled to start, it's pretty cheap and I can get it from my local shop. Quote Link to comment Share on other sites More sharing options...
Drewie Posted December 28, 2014 Author Share Posted December 28, 2014 (edited) Oh and I forgot to add... The bloomin' pullstart broke again on boxing day! Thankfully I was able to reattach the spring that had snapped and get it working again, although I'm not sure how long this repair will hold, so I'll be ordering a new pullstart too. Edited December 28, 2014 by Drewie Quote Link to comment Share on other sites More sharing options...
Drewie Posted December 28, 2014 Author Share Posted December 28, 2014 Erm... I could use a bit of help. Whilst stripping it down and rebuilding, I may have damaged the HSN housing irreparably. Don't ask how, but it's broken. Any ideas on where I can get a new one? I've found the part I need on an american website, but with so many of the mach .28 engine around, I'm amazed there isn't one closer to home. Anyone able to point me in the right direction please... I'll owe you a mars bar! (or other confectionary of similar value) Cheers Drewie http://www.nitrohouse.com/Needle-Main-Housing-Hyper-21_p_9188.html Quote Link to comment Share on other sites More sharing options...
Drewie Posted December 28, 2014 Author Share Posted December 28, 2014 Never mind. Found it hidden away on modelsport http://www.modelsport.co.uk/ho-bao-.21-main-needle-hub-valve/rc-car-products/27207 1 Quote Link to comment Share on other sites More sharing options...
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