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i need some help...

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J

Jamxx85

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hello.

i have a tmaxx 2.5. i just installed a new coolant head (trinity monster) and when i tried to start it it would not. i thought at first it was flooded, cleared that, and then tried again. it did the same thing: spun for about 3 seconds, tried again, and it locked up. I checked my air filter, and desparingly found that it was full of fuel. i'm a newbie to the nitro class, and if anyone can help it would be very much appreciated.

PS- www.beatyourtruck.com/beatings.html - check out the rustler video! (its mine! :thumbup: ) only upgrades p2k 27 turn motor.
 
i dont have the awnser but would liike to know since I've got the same pprob
 
well guys it sounds like you both installed something wrong such as not installing the little aluminum gasket but that doesn't efect the engine in that way. so many things could go wrong how tight did you tighten the bolts on the head and in what way did you tighten them . another thing is that if you didnt in stall that gasket in the head the compression ratio goes up. that will make you carb settings out of wack. and for all the fuel in your carb thats kinda weird it sound like your needles are way to rich . its hard to tell with out actualy fiddling with the truck. try if you have one your local hobby store they may to be able to help.
 
sounds like it could be a number of things so lets try the simple stuff first, remove the glo plug and turn the mill over, does the head fill up with fuel as well as the carb? do you see the piston moving when you try and turn the mill over? is this a 2.5 with an ez start system? is it possible that your old head settings were so rich that you are sucking way too much fuel with the new head? If all you did was change heads then it really shouldnt be any drastic changes that would cause your carb to fill with fuel like that, If your ez start is turnin over,then its rapidly pumpin fuel to the carb and flooding it out before it even has a chance to fire, are you sure your cooling head is compatible with the 2.5(without shimming?)
my guess would be that the piston starts to move just long enough to flood out and fill the carb with fuel, and then locks up and wont move again until you empty and manually unlock it, I could be way off here but this happend to a 2.5 I had once when I tried an aftermarket head, I ended up putting the old one back on and moved on, hope this helps, good luck!
 
The first thing to do is check to make sure your glow plug lights nice and bright, and your glow ignitor is charged up good D)

As a general rule of thumb, when the air filter is full of fuel, and the engine won't turn over, your flooded. Way too much fuel into the chamber, it fills with fuel, and fuel doesn't compress like air, so instead of squishing and compressing the air,then shooting it out the exhaust, it just sits there.

When your filter is full of fuel and it won't turn over. Pull the glow plug out. turn the car upside down. Put a rag over it, and pull. It'll clear out all the unburnt fuel. Put the plug back in and try to start again.

It is possible that your needle settings are way too rich, getting you flooded before it has a chance to fire.

If you are continually flooding and locking, try adjusting the needles for a bit less fuel 1/16th a turn at a time until the hydrolocking stops.

I got mine started way too rich (locking often), but after I adjusted the needles not only did I save a ton of gas, it ran like a bat out of hell.

Hang in there, it does get easier everytime out.

BTW be very carefull clearing out the fuel. One of our members here at RCNT accidentaly got some in his eye clearing out the chamber. It melted his contact to his cornea and he has tohave surgery. I don't know the results, but I can assure you it was no fun.
 
ok, i'll try unrichening my fuel mixture some. i already tried clearing the flood, didnt do much. I am using an EZ start system. The only problem with putting the old one back on is that it always overheated. I didn't change the settings so i'll try that now.:hehe:

ok, better results... after about 7 minutes of flooding, i finally got it started. however, when i did, the truck totally went haywire. i leaned the hsn and the lsn some. i think it was my wrongdoing to lean the lsn because it was set pretty well before i changed my coolant heads. it also took me about 6 seconds of pinching the fuel line and high-strung panic to cut the engine off. results are results after all! i will be working on it over the weekend, posting results as i go. thanks for all of your help guys! dont stop responding!:bling:
 
It definitly sounds rich.

Did you happen to not put the shim back on between the engine head (cooling fins) and the engine block? I know when i pulled the head on my 2.5 to put a different head on, the shim stuck to the head, not the engine. If i hadn't noticed, i would have had problems.

Without that shim in place, it opens you up for problems. Usually air leaks that cause wierd fuel flow results. Plus, you crank the compression to high without it.
 
shim-as in little washer thing? shimming-as in filing or cutting it to fit right? i'm a bit confused...

well, the new coolant head came with another shim so i just put the new one back on and ignored that the other stuck to the old head (i noticed it though). However, if you see a picture of this head (www.trinity.com) it is absolutely huge, and the bottom fin is pressing against the E-Z start motor. Should I file that bottom file until it fits better? it did snug up quite well to the head though. Also, should i use the same shim as i did with the old head. if so, how do i get it out??? sorry for all of the questions guys, but you are being a great help! :) :) :) :) :):sorry:
 
Yes, the little washer thing. I think it's brass, but i'm not 100% sure. I'll see if i can find a pic somewhere.

Here's a link talking about head shim's and air leaks.
http://www.rcnitro.com/rn/articles/fix_airleaks2.asp

This is page 2. The pic on the left is the shim, it goes under the button (pic on th right) and sandwiches between the button and the block to create an airtight and pressure tight seal.

Without actually seeing it though, i'm at a bit of a disadvantage. The head should bolt on securely and evenly. If a fin is hitting something, remove the something or grind the fin a bit so it doesn't rub would be my guess.

Here's another pic showing you kind of where the shim should be.

http://www.rcnitro.com/rn/articles/10_lobudget.asp

I would never recommend running without one. It's soft and more plyable than the block or the head. It's this way to help seal the uneveness (microscopic) of the block and the head button. On some engines you have a cooling head, head button and block. On others, the cooling head and headbutton are permanently connected. More so a once piece design instead of two. I've been told this helps with heat transfer, but who knows.

Here is yet another at the bottom of this page:

http://www.rcnitro.com/rn/articles/ht_rebuild.asp

I subcribe to this mag for this stuff. The nice thing is, the good stuff in the mag is on their website. Well most of it is.
 
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i can post a picture of my truck on my website. (well, i'll make one.) the shim is not exactly what i thought it was. i'll redo putting on my engine head again, i dont mind doing it, wasn't all that hard. :) i think that it might have come off... however, is the shim what you put under the glow plug??? one picture you have is like that, but the other one is the shim under the actual cooling head. sorry, i'm a bit confused now.

whopps... i made a mistake. the shim that you are talking about i didnt notice. i will take the coolant head off later today and will post the result. thanks
 
There is a brass ring that goes between the head and glow plug. This seals that.

There is also a head shim (i believe it's brass also) that goes between the head/head button and engine block. It actually seals the sleeve to the cooling head and gives you the correct compression ratio.

There is one shim (head shim) and one brass washer (glow plug washer). Both are equally important to have in place.

Before someone corrects me on the shim and quantity of, some of the more experienced nitro guys play with the thickness of head shims and quantity of head shims to eek out better performance. I'm not those guys. I just do what is necessary to run and to run well.
 
i'll check the shim today. thanks for your help. i will post results on how well it did.
 
great news! it is fixed. the heat has dropped a whole lot. thanks guys for all of your help! :cheers:

what was wrong is that the lowest fin of the coolant head was pressing against the ez start motor. i simply filed it about an 1/8 of an inch and it fit more snugly than before. thanks again!
 

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