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2.5 Wont Start

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Bighomedog11

Bighomedog11

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Hey for some reason my 2.5 t-maxx wont start up. It will pop and sometimes sound like it wants to start but wont start. It was running fine the other day, and i cleaned the engine with a q-tip and the cotton had fell off in the engine. So i had to take apart the engine and remove the cotton. Once i removed the cotton and put the engine back together i now can't get the engine to fire up..
I need help on why it is not firing up.
 
If its making a pop sound then idk but if its sputterin n tryin to fire but not stayin runnin I would check for air leaks I pulled the head off my 2.5 to check the condition of piston and sleeve cuz I got it used and when I put it back together the head didn't seal right so it would sputter but wouldn't run n u could see really small bubbles between head and crankcase when it was turning over cuz compression was bad did u put any sealant on it when reassembling?
 
brokeitagain said:
If its making a pop sound then idk but if its sputterin n tryin to fire but not stayin runnin I would check for air leaks I pulled the head off my 2.5 to check the condition of piston and sleeve cuz I got it used and when I put it back together the head didn't seal right so it would sputter but wouldn't run n u could see really small bubbles between head and crankcase when it was turning over cuz compression was bad did u put any sealant on it when reassembling?
Click to expand...
No i did not put any sealant on there..
I think i might of installed the piston sleeve the wrong way. I am going to take it back apart and look to check..
How should the piston go?
 
You Should have one side of the piston with a cut out in it...
That side point towards the exhaust....

Anyone correct me if I'm wrong.. (hope I'm not cause I've done it this way in 3 engines)
 
Well i Google a picture of how the piston is suppose to be in. And it looks like i have the piston in correctly. I mean it was running before i opened the motor. Now it wont even fire up.

I tryed to prime it but it would only pop and act like it wants to start up. I also have the little copper gasket on under the head like it suppose to be..

Do you all think that maybe there could be still cotton in the engine?
 
I am thinking about just buying a new 2.5 engine, sense i got this truck in a trade so I really dont know how the motor was taken care of before. But i mean everything looks to be installed correctly.

I also think i know why it is not starting. It looks like my piston chipped. I did not see any chip pieces when i took apart the motor. But when i remove the crank rod i notice the piston looks chipped. I will take pictures.

I also was thinking about getting the 3.3 motor for my 2.5 but i am not sure if it will bolt right on without any modifications.
 
Last edited:
Bighomedog11 said:
I am thinking about just buying a new 2.5 engine, sense i got this truck in a trade so I really dont know how the motor was taken care of before. But i mean everything looks to be installed correctly.

I also think i know why it is not starting. It looks like my piston chipped. I did not see any chip pieces when i took apart the motor. But when i remove the crank rod i notice the piston looks chipped. I will take pictures.

I also was thinking about getting the 3.3 motor for my 2.5 but i am not sure if it will bolt right on without any modifications.
Click to expand...

The 3.3 fits the same as the 2.5, everything is compatible
 
Yeah i am thinking about doing that. Because the piston is chipped and i will have to buy a new piston and sleeve witch will be about 50 buxs. And thats just half way to a new engine.
 
Exactly. .15's are too small for mt's anyways. The best running 2.5 is still under-powered. Fine in the Rustys and Pedes, but not a maxx.
 

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