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Old 01-01-2006, 11:45 PM   #61
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yeah well that would put me in a very bad position becuze thatll mean out of both buggies no engine will run efficiantlty i cant understand it i have given it my all on the engine and 5 mins a go i just finished running it and it got up to 360 farenheight reving fully no idle and no accelerastor real high reving i cant figure its problem out non of my hobby shops will do a check up and pull apart overhaul around me so umm im fucked excuse the french its just i have given it everything and cant get it to run consistantly if i get it running good its got too high temp if i get the temp good it runs with stutter if i get good acc low end top end isnt as fast i just cant get a compremise.
do you think i could send it to sh engines company maybe?
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Old 01-02-2006, 01:32 AM   #62
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and also so you know the engine is only 2 months old from the person i bought the xb8 from with the sh engine in it.
ok say if i overhaul the engine or just pull it apart and re put it together what shall i look for in inspecting it also so you know there is air bubbles going through the intake fuel line upon start up and then it seems ok and clear fuel but is it normal to have air bubbles come from out the engine when its just been stopped is what i mean is that there is bubbles coming from the engines fuel intake connection back through the lines to the fuel tank when engine just stopped sorry for repeating i just being thourough. um and there is residue under my fuel filter so whether its fuel or filter oil there is residue on my fuel lines where the air filter is resting on them.
i am just trying to understand why my engine is doing this and how to correct it also so it doesnt happen again so i might be best to take it to a professional and get a starting point from an ok position and then go from there.
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Old 01-02-2006, 07:29 AM   #63
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You can send it to SH so they can mess around with it, or you can send it to an engine builder. It sounds like you have an air leak, or you are missing some head shims. I can give you a rebuild guide if you want. If you ever pulled the head off the motor, a head shim may have fallen off..........

Also, your bottom end may be too lean. If it was too lean, it would run great on the bottom up through the top, but like you said, it would constantly idle high.

The air bubbles coming back out of the engine indicates overheating and/or an air leak. The air may be leaking out of the inlet on the carb, but when you stop the car and you see the air bubbles and hear a "sizzling" sound at the same time, you are having an overheating problem. The carburetor is probably getting hotter than the rest of the engine first, causing the fuel coming to the engine to start to boil, making the engine idle high and run lean (which would explain the temps)


Does this help at all?
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Old 01-02-2006, 07:34 AM   #64
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also, if you wouldn't mind, I'd like you to try another carb setting.

adjust your carb so that the top end is flush with the needle body.


adjust the bottom end so it is 3 turns out from all the way in

set your idle gap to 1mm.


Now, tune the top so it has excellent power, and then richen it 1/8 turn. DO NOT TOUCH THE BOTTOM END, UNLESS YOU NEED TO LEAN IT TO THE POINT WHERE THE ENGINE IDLES A BIT SMOOTHER.

If you have to, lower the idle slightly. Then pick the car up and give it full throttle for 2-3 seconds, put it down, and get the temp.

What temperature is it running now, and are you starting to get the high idle, rich bog, or lean tap??????


Try this and let me know what it does.
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Old 01-02-2006, 07:50 AM   #65
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ok i will try that tomorrow as its late right now also i did take the head off before to get the glow plug off and back in if i pull it off tomorrow before i try your settings strategy previously mentioned in the thread above,what should i look for on the head base or top of crank case?
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Old 01-02-2006, 08:12 AM   #66
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ok i pulled the head off and sleave out its a little browny goldy burnt colour near the exhaust valve other than that it looks fine and there were 3 copper colour shims (washer type thing), are shims i presume maybe i could add a couple of shims to make the plug a little higher ?
how many should there be 3 or more?
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Old 01-02-2006, 08:26 AM   #67
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you really need a caliper to measure the shims, so I can tell you exactly how many you need. What fuel are you using?
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Old 01-02-2006, 09:37 AM   #68
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in the engine manual it says head gaskets is 0.20 mm and the other is 0.10mm but on my actual engine there are 3 of them so he may of put the spare one on?
i am using a nitro fuel from my local hobby shop called AT racing premixed fuel which has 10% synthetic oil and 5% caster oil which has 16% nitro content.
i heard about a need for 18% oil for some engines.i also heard if you leave the fuel in the sun or in hot temperatures it can
damage thefuel , my van will get pretty hot in the sun inside temp will be hot inside the van where i had my fuel.
also is there a way to make your own fuel like mix methyl alcohol,nitro methane and where/what oil would i buy to mix it?
but first i need immediate attention to my engine ive set the needles as stated ill wait till tomorrow morning to give it a try .
i also replaced the fuel line with the spare line which is 3 times as long now so i can get more fuel in the tank after the engine has started.
other than that my engine should be air tight i even checked the lines in water by blocking an end and blowing the other end with the line in water proved air tight. i am starting to wonder whether the owner who had this buggy from new didnt break the engine in properly.
could maybe the carb be inefficient how would i check that?
umm umm trying to think what i can do maybe let it idle for a tank to warm up nicely in a rich setting and then tune from your settings above hsn flush and lsn 3 out from closed.
would running the car real fast accelerating it from low to top end for a straight 1/2 tank be bad for it i dont know what the limits are its obvious you wouldnt run it flat strapfor full tank say following it in a car for instance but if i kept lapping past me on the road accelerating through to top speed for 1/2 tank would it harm or make it run high temp.
all i want it to do is be able to run it for as long as i want without it stalling and not run too hot im wondering if its too much too ask from this engine however we will get there i have faith lol
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Old 01-02-2006, 02:43 PM   #69
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I see a large problem with your head shims right now. Most engines are shimmed for 20% nitro from the factory, and whoever had the motor before you shimmed it for 30% nitro. When you are running your 16% fuel, the engine has a lower compression ratio during combustion. Try removing 1 head shim, or maybe just run the .020 shim with another .005 shim to lessen the gap even less.

You do NOT need 18% oil content, that puts a lot of "gunk" through the engine and you won't get the best performance. Try a fuel with about 10-14% oil content, those fuels work much better. I run O'donnell 30% nitro and I believe the oil content in it is somewhere around 11%.

Running WOT for a 1/2 tank won't help too much, just run it around ar a moderate throttle level for a while and check the temps.
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Old 01-02-2006, 05:27 PM   #70
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wot = with out throttle or full throttle?
ok thats all my local hobby shop supplies ill see if he has higher nitro content.
and im on my way there for gaskets etc i shall get some engine cleaner while im there is there a cheaper substitute ? as i have found a real car lubrication for like 10 buks for 750 ml i use for after run oil insted of paying the same for like 100ml of after run oil. is there a cleaner thats cheaper i can use to flush the engine out that i can buy at the supermarket.
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Old 01-02-2006, 07:59 PM   #71
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WOT=wide open throttle..And you can use mineral oil for after-run oil.You can find it at wal-mart,walgreens,and some other places.It's in the pharmacy section and is a laxative,well thats what it says on the bottle.
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Old 01-03-2006, 08:30 PM   #72
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Hi guys,

Ive been to on-road for a while but would like to get into off-road, im thinking of getting the Kyosho TR-15 stadium force to start with, what you guys think of this car...are there any hop-ups for this? are there any potential problem with regards to the uspension system (F-1 style)

Thanks.
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Old 01-03-2006, 09:55 PM   #73
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k617nu-b
i am not sure about the tr-15 from what i know of these 1/8th buggies i recomend you get a kyosho inferno mp-7.5 or an inferno mp-7.5 kanaii 1,2 or 3 or even an inferno mp-777 as there are alot of parts availability on the net like ebay also thay are very strong and are a good race buggy thats my opinion i have an x-ray xb8 which i chose over the inferno range.
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Old 01-04-2006, 02:51 AM   #74
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Quote:
Originally Posted by k617nu-b
Hi guys,

Ive been to on-road for a while but would like to get into off-road, im thinking of getting the Kyosho TR-15 stadium force to start with, what you guys think of this car...are there any hop-ups for this? are there any potential problem with regards to the uspension system (F-1 style)

Thanks.
You would have too much trouble finding parts. Either, go with a 1/10 truck like the Associated RC10GT or a 1/8 buggy like one of the million Ofna buggies out there today.
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Old 01-04-2006, 04:53 AM   #75
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yeah guys it seems if i lean the engine out to good performace after it gets to high temp and is running well all of a sudden it runs with that bog sound like its getting alot of air but no power acceleration it sounds like its starving for fuel but sucking in air like its not firing and running at the few laps before this happens though if i richen it up any more it will sputter like its too rich so i can not win with tuning it.
it seems it was running to high temp before because of full throttle runs though when on track with only 1 straght to wind it out on it runs cooler but still i have this bog trouble.
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