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Dickylew
27-12-2008, 03:48 PM
just got a hobao st black edition for my son for xmas and i cant get the engine to fire.
It didnt help that the glow starter was faulty i bought a new one today and is now working
Ive tried heating the engine with a hair driver first and am using number 4 and five glow plugs.

After a few pulls on the starter the pull cord just goes solid i think due to flooding i remove the plug and drain excess fuel but the dam thing just wont fire, ive checked the plugs are glowing but have run out of ideas.

Help please.

3975dave
27-12-2008, 04:21 PM
Try starting it with a loose plug. This should lower the compression slightly so the engine spins faster.

Dickylew
27-12-2008, 04:27 PM
thank you, i did try that and it was a bit easier to pull but still did not fire.

Charging the glow starter overnight and will try again tomorrow any tips would be appreciated,also when the pisto gets stuck at tdc what is the best way to fre it up?

Gnarly Old Dog
27-12-2008, 05:22 PM
Try also the following:

1) Re-check all engine needle valve settings. Most engines come fairly well set up but occasionally you may experience a rogue and if the carb isn't set correctly it will never fire. There is likely to be 3 settings to try - the main needle, the low speed needle and the idle screw. Check the instructions for what the 'correct' setting for all of these should be.

2) Assuming that the carb is set up correctly, quite often priming the system won't give enough fuel to sustain a fire with a new pull start engine. Do as 3975Dave suggests and back off the plug to ease the compression but first, you may also try to drip 3-4 drops of fuel directly into the combustion chamber by removing the plug first. Be very careful not to flood the engine but this, in addition to a primed system has never failed me yet.

3) Give the plug a few seconds on the glow starter before attempting the pull. Once it does fire, keep the starter on it for upto 30seconds whilst the engine warms through.

You will need to run the engine in before it will rev cleanly and run properly. Some engines seem prone to blowing plugs during this process as quite often there is minute particles of metal swarf that ends up damaging the plug element. Never ever run it without the air filter. Sorry if this sounds if I'm preaching - but I've learnt the hard way ;-)

It will work but they can be very frustrating.

As for a siezed engine at TDC - I've only experienced that once and the only way I found to feel it up was by removing the engine from the chassis and gripping the flywheel in some grips / vice and turning the engine very carefully.

New engines are tight - some are worse than others but once run in, they'll be fine. Just make sure you take your time with the running in process - you'll do more harm than good if you try to rush this - it is the most vital aspect of defining the engine's life (other than running it without an air filter!!)

Good luck.

dave g
27-12-2008, 05:52 PM
when the engine gets stuck at tdc due to the pinch in the new liner then lever the flywheel round from underneath with a large flat bladed screwdriver thru the chassis where you can see the flywheel,no need to take engine out.

the hyper engines come set very rich,try turning the lsn clockwise half a turn after you have cleaned it out of fuel then try again,alternatively you car pinch the fuel line hard between finger and thumb and keep pulling on the engine with glowstarter attached,this will lean the engine out,it should get to a point where its almost out of fuel in the crankcasing and fire up..its a cheating way of getting a rich engine to fire up.

no need to touch the hsn/main needle to get it to fire up.

andy-aj
27-12-2008, 06:17 PM
Hi,

Have a read all the way though. Hope it helps.

http://forum.hertsnitromodelclub.co.uk/viewtopic.php?t=10

Andy

Dickylew
27-12-2008, 07:12 PM
thank you all for your advice will have another go tomorrow and try some of your suggestions.

kind regards

Adam Skelding
27-12-2008, 10:39 PM
Another thing is to get some heat into your engine before you start.
If you've left the car in the garage overnight, it will have got very cold and will not be easy to start due to high friction.

Borrow the mrs's hairdryer or your own and warm up the chassis and heatsink head with the hairdryer for a good 5 mins. Then leave for about a minute to let the heat 'soak' through to the engine and 'free' the engine up.

If you don't have a hairdryer, the footwell of a car with the heater on is as good a place as any or ontop of a radiator.

:thumbsup:

Dickylew
28-12-2008, 12:19 PM
well ive tried again for about an hour and the dam thing wont start just getting ready to give up,taken the skin off my fingers trying i knew when i bought it they could be difficult but this is crazy ive tried everything beggining to think ive wasted my money.

Ive heated it with a hairdriyer, backed off the plug, ive tried putting a few drops of fuel in the port directly and leaned the carb a bit.

When i leaned the carb it did try to fire once then nothing, ive pulled the starter so many times i must have run it in without it ever being started!

If anyone can help i would be grateful.

dave g
28-12-2008, 08:15 PM
if you fill in your profile with location someone may be able to help you locally..

Dickylew
29-12-2008, 09:11 PM
Finally gave up today and took it my local model shop i paid them a few quid and they got it running.

Turns out there was a problem, the throttle linkage to the servo was totally out and wasnt opening the throttle, they said it would have never started.
They reset this along with the brakes as these were incorrect also.

Also the engine was extreemly tight. they poored some kind of lube down the glow hole and pulled the starter and lossened it all up.

Took it home and it started on second pull hooray, now having fun with my son, running it in before giving it some welly, surprised how fast it is even on low throttle.

From my expeirience if you have this model and it wont start check all he above.

:thumbsup:Thanks to all that replied.

Garry Driffill
29-12-2008, 09:34 PM
Glad to here you got it started in the end :thumbsup: