.28 engine tuning - it was ok now it's not?

[Sandmaster Ben]

Hey guys, my nosram evo .28 monster was running a dream until I gave it good run out last weekend and it had some heavy landings and a bit of water spray etc. Now it runs but wont go over half throttle without seriously bogging down and cutting out. i have always run it really rich but now it wont run at full throttle at all. Any ideas?

[Sandy Ravage]

there are 2 types of engine bog,lean and rich.

if its starving of fuel it will probably run ok when cold and first started up but lean bog when it starts to get warm.

if its a rich bog it will struggle to run properly when cold but get slightly better as it warms up,usually kicking a lot of smoke out.

With you setting the needles back to factory settings it is too rich and what it is trying to do is, the unburnt fuel is trying to put the glow out in the glow plug.

If its too lean then the lean bog occurs because there is not enough fuel to let the engine rev.

[Nitroholic]

If it's been a sudden switch, you also need to give the car a thorough going over.

Check the throttle servo is opening the carb properly, check all the fuel lines ( have had split lines do similar before) also check the air filter isn't clogged or damaged.

Worth checking hte glowplug is OK as well

[Sandmaster Ben]

i took the head off the engine and gave everything a good clean and put plenty of after run oil into it through both carb and head. Think i need to play with the tuning again,it may have just jumped out of the settings with a few of the heavy landings.

[HATZY]

if the air filter came off at any point, check for small stones in the carb

[Sandmaster Ben]

no it didn't, they are pretty well fixed on in the hoboa hyper st's, they have an outer and internal filter as well. It would run around at half throttle but as soon as i blipped it is would stutter and would not rev highly at all

[Sandmaster Ben]

right guys, been to a rc meet today and my we tuned the car and it was running slightly better but blew 2 glow plugs. so not a happy chappy. It recommends the Nosram R5 glow plug, is this the same as any R5 plug?

[Sandmaster Ben]

is the os 8 glow plug a medium heat and suitable for a .28 engine running 25% fuel

[Nitroholic]

It's OK....ideally you should use a cool or medium/cold plug

[Sandmaster Ben]

give me an idea pal, i don't have a clue, the info i have with the engine specifys an Nosram R5 plug but 'sure theres an equivalent thats more common?

[Sandmaster Ben]

An nosram R5 plug which is states is coldish yeh? so i assume the OS R5 is the same thing?

http://www.osengines.com/accys/glowplugs.html

[Jumper]

looks like it. os 8 are usually found in .21 rather than .28

[Sandmaster Ben]

yeh i dont thing the os 8 is suitable, think i need something colder. can't believe how expensive the little plugs are lol

[chrisknights]

a os8 will be fine mate in your engine , i used them in all my .28 engines set for my Go engine which needed a hotter plug , with your bad landings , you might of knocked the cooling head and loosen the bolts causing a air leak , so check for air leak , plus having put after run oil in your engine to much and it will run alittle boggy til you clear it out , change plug , check air leak and tighen up cooling head bolts and see what happens if noting then reset the factory settings

[Sandmaster Ben]

ive reset it back to factory now and going to start with that again, ive checked all the engine internals, seem fine however the head and bottom of the plug is brown so might have been running it too lean? so will get new plug and start from scratch