Tuning advice needed

[Sycko]

Hi all, can anyone offer me advice on tuning this STS engine please, it seems to bog out when I try to full throttle, I have just dug it out of a 4 year sleep in the garage.

 

[lokky]

So what happens if you lean or richen the hsn? I would lean first.

What temps is it getting to as my STS only wakes up after getting to 220F.

Assume the nitro fuel isnt 4 years old.

 

[Sycko]

So what happens if you lean or richen the hsn? I would lean first.

What temps is it getting to as my STS only wakes up after getting to 220F.

Assume the nitro fuel isnt 4 years old.

Hello and thank you for replying,

the Fuel is new 20% bought just a few days ago, I returned everything to factory settings with it being stood for so long, I got the engine to start first by tweaking the lsn and idle and thought I will sort the hsn out when its running but no matter what I try it just wont have it, not sure on the temp as I don't have a temp gauge, this engine has always been a pig to tune.

 

[lokky]

How loose/tight are the needles? Perhaps the o-ring in the needles arent sealing so well after all this time?

If adjusting the hsn sees no change in performance then take the carb off, disassemble and soak, give it a good clean.

I cant remember if some STS carbs were problematic, but i know the hpi k4.6/5.9 carb fits and works in the sts 28/30 as used in mine.

Does it restart ok after warming up?

 

[Sycko]

So what happens if you lean or richen the hsn? I would lean first.

What temps is it getting to as my STS only wakes up after getting to 220F.

Assume the nitro fuel isnt 4 years old.

Hello and thank you for replying,

the Fuel is new 20% bought just a few days ago, I returned everything to factory settings with it being stood for so long, I got the engine to start first by tweaking the lsn and idle and thought I will sort the hsn out when its running but no matter what I try it just wont have it, not sure on the temp as I don't have a temp gauge

How loose/tight are the needles? Perhaps the o-ring in the needles arent sealing so well after all this time?

If adjusting the hsn sees no change in performance then take the carb off, disassemble and soak, give it a good clean.

I cant remember if some STS carbs were problematic, but i know the hpi k4.6/5.9 carb fits and works in the sts 28/30 as used in mine.

Does it restart ok after warming up?

Yes, restarts fine after warming up, just seems to be lacking that top end performance, good idea with the carbs I will give them a good strip down tonight, the lsn seems pretty loose but the others are nice and tight, what needle setting do you have yours at as default? I don't have the manual anymore so went with settings I found on the internet

 

[lokky]

I don't know off top my head but it will vary anyway.

Do you have a fuel filter?
Have you checked fuel tank lid seal is good?
Is the pipe gummed up with old fuel?
is the rear engine exhaust seal good?

 

[Sycko]

I don't know off top my head but it will vary anyway.

Do you have a fuel filter?
Have you checked fuel tank lid seal is good?
Is the pipe gummed up with old fuel?
is the rear engine exhaust seal good?

all good points, no fuel filter. having being out the game for so long I forget some of the basics, I will give it all a once over after work and get back to you, thanks very much for the advice ??

 

[lokky]

Try a new glow plug?

Sometimes it's a bit trial and error.

 

[guinnessdublin]

Worth checking the engine head bolts are tight, had this the other day where my engine seem to lack power & one of the bolts was loose the exhaust gasket was worn also!??

 

[Sycko]

Worth checking the engine head bolts are tight, had this the other day where my engine seem to lack power & one of the bolts was loose the exhaust gasket was worn also!??

thanks guys, ive checked all but nothing stood out so I replaced the tank, piping, exhaust and gasket, glow plug, not had chance to run it yet as as usual here in the UK is pssing it down ?, I will let you know how it performs next time its out. Thanks again

 

[Sycko]

Hey guys, ive tried everything with it, me and a friend couldnt tune it at all. Replaced everything else so I reckon the engine could be stuffed after sitting idle for so long, thinking of changing it to an Electric but need to research it, thank you all for trying to help

 

[fuelfather]

I'm willing to bet you need to lean out the HSN. Let the truck run until down to half tank and see if the engine doesn't perk up a little bit. Also check that the air filters haven't begun to fall apart. I pulled out an older .25 and put it in and the filters i had, 6yrs old still sealed never used, fell apart as i opened the package.