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The 2.5r is giving me an ulcer!

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T

Tighty Whitey

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I have 1/2 a gallon through the motor so far. It will hit 300+ degrees within 5 minutes WITHOUT thrashing it either. I have had 3 diff people help me try to solve this problem but it will still get hot! I have set the motor to oem specs several times and then tune but it still bakes. The motor seems to be running rich because blue smoke pours out the back. I also have my windshield open so the motor can breath.


Honestly do you think I have damaged anything internally?



Does anyone else have these problems?
 
sounds like a air leak. if you have a leak no matter how rich you run it, air will come in and make it lean. first check your tank lid, i think the revo had a problem with the lid sealing. change your fuel lines, check your fuel filter if you have one. maby take the carb off and make sure it isnt clogged. seal the carb, seal the backplate. make sure your head screws are tight, and eveny tightend down.
 
^^Ditto^^ to all of the above. The 2.5r is actually an easy mill to tune, but if there is any air leak, forget it.
 
someone correct me if I'm wrong because I've never dont this befor but i heard you can use some nitro spray (the cleaner stuff) to find your leak. start the engine and let it run. spray small spots on the mill, (carb neck, fuel inlets, backplate, ect.) with the spray cleaner. if the mill dies then that is where your leak is.

let us know how it goes tighty..
 
Getting ready to go outside right now and try that. I checked my tank last night and it has a good solid seal on it. You can actually hear a small pop when you open the tank
 
just curious, what color is the o-ring on your tank? the good one is red and you can buy them separately now. if yours is blue, you might want to go ahead and change it now before it gives you headaches later. let us know how it goes!
 
Yes Beason you can do that, I thought it was WD-40 though and the mill would die. Thought combustible cleaners would cause it to lean out and idle to inscrease. I might have it backwards though, I just got done working out.
 
No air leaks anywhere, sooooooo I went across town and ordered a TM323 for my Revo! Not gonna screw with this motor anymore
 
Ok, I had my car out for it's last couple of runs and now have an onboard temp gauge installed...

I've ensured that the sensor is on the opposite side of the exhaust port and it's showing some scary high temps....

320-340...

I've richened the mixture up, it then would not change into 2nd gear, so i leaned off slightly it then changed into second ok and the temps started to drop a little, but not down to what they should be..

I'll check tommorrow for air leaks and check the carb for blockages..

Just a little worrying as it's very cold here in fact just above freezing so i dread to think what it'll run at in the summertime..

Would it help to make some holes in the windshield...???

Should i got back to factory HSN and LSN settings and restart the tune.... It's had a full 5 litres of fuel through it now so it's well run in..

Bristar... Hot n bothered
 
Bristar said:
Ok, I had my car out for it's last couple of runs and now have an onboard temp gauge installed...

I've ensured that the sensor is on the opposite side of the exhaust port and it's showing some scary high temps....

320-340...

I've richened the mixture up, it then would not change into 2nd gear, so i leaned off slightly it then changed into second ok and the temps started to drop a little, but not down to what they should be..

I'll check tommorrow for air leaks and check the carb for blockages..

Just a little worrying as it's very cold here in fact just above freezing so i dread to think what it'll run at in the summertime..

Would it help to make some holes in the windshield...???

Should i got back to factory HSN and LSN settings and restart the tune.... It's had a full 5 litres of fuel through it now so it's well run in..

Bristar... Hot n bothered
Click to expand...



:OMG: I thought my motor ran hot.
 
beason said:
. first check your tank lid, i think the revo had a problem with the lid sealing. change your fuel lines, check your fuel filter if you have one. maby take the carb off and make sure it isnt clogged. seal the carb, seal the backplate. make sure your head screws are tight, and eveny tightend down.
Click to expand...


OK, i have similar issues.. I have now changed all my fuel lines..

Unsure of how to tighten the seal on the fuel tank, i see two philips screws inside the tank lid, are these to create a btter seal.. i ask coz my lid is not popping when the fuel tank is empty although it does make a load pop when opened with fuel inside when the cars been running.. which would indicate to me a good seal on the fuel tank lid...

I'd assume next place to check for air leaks would be the carb, not an area i've messed with yet, i've bought a spare seal just in case, but i would be grateful if someone could tell me the quickest way to remove the carb to check for leaks.. and to check the seal..

Any help on this will be appreciated.. although since changing the fuel lines i've not had chance to run the car so the process of elimination has not been tested yet..

Also just thought i'd mention i've noticed some sort of deposit half way along the exhaust system, where the join is... Is this possibly a leak of some kind that could be a part of the problem.. or is this normal... it's a sort of greasy deposit.. not loads of it but enough to be noticable...

Cheers fellas..

Bristar
p.s as mentioned i'm doing all this coz i'm getting some very high temps ... 320-340 and on one occasion as high as 400....

Oh i've also cut many many small holes into the windshield to increase airflow..
 

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