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Problem keeping trx2.5r running in my revo

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before i took the truck in to the LHS i had the LSN about a 1/4 out from flush and it still bogged down. and the HSN was about 4.5 turns. but then he screwed with it and turned the LSN almost all the way in and the HSN to about 3.75. i use after-run oil after every use and the air filters get changed and oiled just about every time i take it out dependin on how dirty i t was where i was playing if I'm in the street i usually didnt change it. and the dude at the LHS said that anything in the 40's was bad compression but he said 50-53 was about right for compression. now thats just whta he said I'm not sure if thats what the correct compression is for them. yes i took the mill apart to check everything out when it started acting up and everything was in good working order now i have not messed with the skipper clutch yet could that be the problem and if so how do i know if it is working correctly is there any special tricks to it.
 
Unless you doing a lot of big air jumps tighten the slipper down all the way and then back it off 1/4 turn or so. Also make sure you pads are all there. The LSN being "flush with the housing" is not flush as in screwed all the way in, it's flush with the carb housing.
 
yea it was flush with the housing not screwed all the way in. but when i took it in the guy screwed it all the way in and adjusted it out about an 1/8 turn and thats it he said that it ran better at that setting because the setting i had it at was to fat. ok ill try that with the slipper clutch and all the pads are there and in good shape
 
Stupid question? What kind of glowplugs are you running....and I second that the LSN seems lean....also if you take off the air cleaner can you see a small opening on the slide of the carb when you look down at it? There should be approx. 1-1.5mm of an opening to get the truck up an running/idling correct. I've had that be a problem before with taking off/launching. It would die on throttle pull or be very hesitant and die due to an incorrect idle adjustment...even though it would idle correctly standing still.
 
I use McCoy MC-59 and OS A8 plugs primarily.

Yes, when you remove the air fliter, the carb opening should be a 1 to 1.5 mm opening at idle and the carb should return to that set-up when you let off the throttle trigger. If it doesn't, or sticks, you need to check for binding in the throttle/brake linkage and re-center your servo. Also, check your trim setting on the TX. If it suddenly opens up on you when you're not touching the TX, could be a glitching problem with your electronics. Just want to check and make sure you have no exposed wiring and consider putting a piece of fuel line over the header sprng.

I don't think it dying at throttle up has anything to do with your idle screw setting. If you have set all your needles back to factory and still cannot get it dialed in, then I'd pull the mill and break it completely down. Clean it up really good. Take the carb completely apart and make sure all the little gaskets are there. Clean it up and blow compressed air through it. When you put it back together, put RTV sealant on the back plate and carb. throat, really seal that sucker up! Also, check your fuel line and fuel tank for leaks and change those out if necessary.
 
I ran A5s in mine and they are what held up the best for my setup

2.5r running at about 85 farenheit ambient temp and 220 engine temp
 
When I ran the 2.5 best perf and longest lasting plugs were McCoys MC-59close second was the OS followed lastly by the Traxxas plug (can't remember the number).
 
I've just been runnig ths stock traxxas plugs in mine nothign else should i try and run a differ plug
 
what the difference between the plugs everyone always says the stock traxxas one are the best for the stock motor. should i maybe try those mcCoys
 
I don't know from a technical standpoint, but my experience is they tend to last longer and burn a tad hotter.

Keep in mind, everyone doesn't own YOUR rig, brother! What works for one may not work the best for you. Give them a whirl and make your own decision, but I think you'll be happy with the McCoy's.

I liken it to a Chevy dealer telling you Delco plugs are the best for your car, when Autolites may improve your gas mileage.
 
From my experience the Traxxas plugs suck. But don't go over and say that or ask at the Traxxas board, the Nazi's over there will slap you with the wet noodle!
 
Yeah... I saw that happen. I think I asked what the best plug for winter applications for the 2.5 is... I got 14 replies saying the traxxas plug. I've never even owned a traxxas plug. All I run are OS's.

I took someones advise here and tried the mccoy mc-59. It ran more steady than my OS #8, but I've found that the 2.5R just doesn't like to run very well when the temps are below 45. Even 40 is too low. Today it was 38 and it tuned like crap no matter what I tried. Even though, last weekend, it was 50 degrees and it just screamed! Ran ok around 240-250, wheelies whenever, idled smooth...

What I've found when the temps drop below 45 is erratic idle, tune seems to change (lean to rich) even if you leave the settings alone. I just think the engine cools too fast with the head it has... I have half a mind to dig out that old beat up 2.5 cast head and throw it on just to see how it does. We all know how well of a job it cooled the engine ;). God forbid I utter those words at the traxxas forum though. Nazi bastards!

I have to say though, I've found some helpful stuff about the revo over there. Speaking of which, I snapped an axle today... very weird.
 
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stop bitchin and get an os TM or TZ and be done!!!!

i never put a stronger engine than the TZ in a truck and the TZ does more than enough
 
Hmm, don't see anyone bitchin' just someone looking for help. Possibly dropping over $200 on a mill doesn't seem like it might be a viable option for him right now.
 
here's my .02 on the issue. first of all, the plug thing matters. i did a little experiment when i first got my revo. the biggest difference will be seen by using a long or a short plug. the 2.5r liked the long plugs best. os lc3, the traxxas crapper, or the mc59. this seemed to be the case with mine and a couple others. you will get more compression with the longer plug because it takes up more room in the combustion chamber. i like the lc3 but as everyone has said that is a personal thing. the only thing i can say is that i'm pretty confident that the performance is better with a "long reach" plug. temp wise, most of the long plugs are pretty hot. a colder plug will retard the combustion cycle and you will compromise performance. the second thing i found was that the 2.5r sucks if it's not up to temperature. usually around 230 and up. i would run mine a little lean to get it to temp and then richen it about 1 hr. if you stop running and it cools down, you gotta start all over again. i asked the traxxas guys about this on the phone and they said it was a side effect of trying to get that much power out of the mill. it's kind of tempermental. as to your needle settings, i would set the needles back to factory and start looking for other things that may be killing it. air leaks, fuel delivery, excessive loads like bad clutch shoes or faulty one way in the starter. if nothing else turns up, try another carb. if you just can't get one, pm me and i'll send you one. i've got an extra. hope this helps!:cheers:

edit: oh yeah, 4 out of 5 2.5r's ran better with the stock head on 'em. probably due to the temp thing.
 
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