Thunder tiger tomahawk bx- help please!

[Hippopotosaurus]

I've been having issues with the engine on my buggy and saw another thread where people have had the same problem. I started to look for a replacement and preferably a new exhaust system to go with it but it seems like the exhaust on the tomahawk come out on the opposite side to those I've seen on modelsports website- is this just me being an idiot? Potentially, but I've never done anything like this before so here I am asking

Secondly, is there anything someone can recommend for a decent speed, but under

[Hippopotosaurus]

[Joshyboy89]

What's wrong with the engine? Same one as in my ST?

[Hippopotosaurus]

yeah its the same one as the st- for some reason if the car flips upside down for more than 5 seconds it cuts out within a minute and then you cant start the engine again until its cooled down- it wont prime at all, the fuel just goes straight out the tube and back into the fuel tank before I have time to even pull the pull start again :s

 

To be honest though I've always struggled with the needle settings- it seems to need something completely different when you start it compared to when its warmed up a bit

[Hippopotosaurus]

the break in procedure that comes in the manual is not exactly... standard

[SirusDviruS]

Never tune a cold engine, your always be chasing the tune about.

[Hippopotosaurus]

maybe, any ideas on why it might be cutting out when it flips upside down?

[Joshyboy89]

Almost all nitros will cut out when they flip upside down as the fuel pick up is in the bottom of the tank.

[Hippopotosaurus]

Really? I suppose it makes sense. Still the issue with not being able to start it again afterwards, any thoughts on that?

[SirusDviruS]

maybe, any ideas on why it might be cutting out when it flips upside down?

Not maybe, defiantly.

Air leaks may be compounding the issue your having mind.

[Hippopotosaurus]

How can I test for and fix an air leak?

[Shudson]

Really? I suppose it makes sense. Still the issue with not being able to start it again afterwards, any thoughts on that?

 

Try opening the throttle slightly.

[Hippopotosaurus]

It won't prime when it's hot, I cover the exhaust and pull the pull starter but the fuel just goes straight back into the tank rather than up to the engine

[SirusDviruS]

I'd be checking the exhaust gasket (against engine) and the silicone joiner for leaks first based on that info mate

Have you got the silly TT exhaust where the pressure line goes into a hole rather than onto a barb?

[Hippopotosaurus]

The exhaust gasket is definitely tight- if there's a leak there its not because its loose at least. However, having looked at the silicone joiner it is a bit looser than it could be, but then if that was the problem why does it still prime when the engine is cooled?

 

anyway, here is a picture of the engine setup- I assume this is the 

 

 silly TT exhaust where the pressure line goes into a hole rather than onto a barb

that you're referring to

 

[SirusDviruS]

Very good point you made with it priming cold.

This is going to be a process of elimination, best to start with the less in depth things even if they are less likely.

Yup that's the exhaust I thought. Some diameter fuel pipe doesn't fit snug enough in the hole causing a lack of pressure in the tank. Check it's snug.

Take the lines off and blow them through or replace if you have spares, clean any fuel filters.

Take the tank out, leave the tubing on. Submerge in water, block off one line, blow down the other. Does the filler cap leak? Or any other part of the tank for that matter.

Take the silicone joiner off, inspect for splits, refit with new cable ties, nice and tight. That's a tight angle it's at.

Check all your needle settings. Do the carb gap first then set your LSN HSN to factory (will need to tune later) do this with the servo linkage disconnected and the carb rotated shut.

If you have carb imbalance and the LSN is super lean it will struggle to get fuel past the carb.

Reset the throttle servo horn and linkage to carb (trim on TX zero'ed before hand)

Failing all that, check cooling head bolts are tight, remove carb and back plate and re-seal with RTV/Instant gasket. Would be worth doing the manifold too.

Edited April 24, 2014 by SirusDviruS

[Hippopotosaurus]

Great - thanks for the help, I'll check most of those things tomorrow but I probably won't be able to run it properly for a couple of months- exams to thank for that lol hopefully that'll get it sorted... If not it might be time for a new engine

[SirusDviruS]

I'm extremely confident you won't need a new engine

[jamie91]

i had almost the exact same issues your descrbing with my tomahawk ST ( same engine/exhause etc) turned out to be a faulty carb.

once i replaced it i had no issues and its still running strong