Hi i have a Thunder Tiger PRO-12BXS ( getting new car and engine soon) and it has been very unkeen to start whithin the past few months, i took out the glowplug found that it was very dim so i replaced that and still no luck, i have tryed different mixture setting but still doesnt help, it usuly takes 25-40 pulls to get it started then about 30 seconds of careful reving before it will go, it sounds choked during that 30 seconds, once it is running it works fine.

Any suggestions of what could be wrong?

Thanks Ben

Empty glowplug battery?
Too many turns or too little turns of main needle?
Primed too much?

Battery must be fullcharged and glowplug must glow about light orange.

Read in the instruction how many turns main needle must be before start the engine, to example 1.5-2 turn from closed position.

Too much priming make the engine wet and difficult to start the engine cause wet glowplug. Take out glowplug and turn the engine many times while pulling with pullstart until the fuel are out of the engine. Blow the glowplug dry, check with battery about the glowplug are glowing and mount at place if ok or replace defect glowlug. Restart again without priming. When the engine are running, adjust the engine to max rpm and turn back about 1/4-1/2 to give engine reliable running and enough lubricating in the engine.

Next time, give the engine some drops fuel in the carburator and connect battery to glowplug, the engine will start after some pull..

Jens Eirik

I have checked the glowplug i have tryed with no priming 1 pul 2 pulls etc i have let the engine air i have reset to stock mixture position and have checked glowplug battery and used 2 different glowplug batterys, the glowplug was replaced yesr=terday but didnt help. its extremely strange

sounds like (if its not the glow plug) you have a slight air leak somewhere that cures itself after running for a few seconds, then when the engine begins to heat up it works ok, have you dismantled the engine? maybe a new head gasket is in order... put it on the compression stroke and see if you can hear air escaping from other than the muffler, glow plug tight? glow plug washer ok?...Rog..also may be leaking around the backplate or carb?..

Thanks That sounds very likely i should have thought of that same thing happened to my zenoah g260 rc. i check that out once it stops raining and i can be bothered to go to the workshop.

Hi all, first post here so please, ask everybodies patience. I have purchased a thunder tiger with a pro 12bxs engine from ebay. I t has a subaru wrx shell and only one shock for the rear of the car. not the four I see on any pics on the net. I assume it is far from a recent model. I have not run the car yet as have not got any nitro yet but the glow plug lights. The pull start retracted once or twice when I first tried it then a few days later after pushing and pulling some of the servos, I tried the pull start and it didn't retract. Only way back was to turn one of the cogs so the engine turned over (rather difficult turning the engine over by hand) then i could get the cord back in. Is the pull start stuffed or can I fix it? I have fixed a pull start on a lawn mower but this is new to me.

Cheers.

Your pull start problem could be one of a many problems. One way bearing, spring or even the cord itself.

I would try to get my hands on some factory/manufacturers exploded views of the engine and pull starter and a parts list. It's nice to know what to expect when you take it apart. If you have repaired a lawnmower pull starter you should have no trouble with this. Then you might be into the carb and engine and maybe not. You're going to learn a-lot and have fun doing it. The sad thing is that I think it's summer there so get going already.

Bill

You are over priming or over choking the engine. If you do remove the glow plug, turn the car upside down and drain what you can, then pull the starter several times, replace glow plug, then start without choking.

Hi!
Are you sure fuel gets to carb? Have you tired holding a finger in front or the carb intake so that you can see fuel entering the carb?

You start the engine at idle...that means having the carb open slightly (1,5-2mm) and as soon the engine fires you give full throttle (glow clip still on) ...Then you adjust the high speed needle for max rpm or slightly less (200-500rpm).

Are you sure you use the correct fuel?
How much nitro?
Have you checked the carb high speed needle housing for any dirt inside?