At my wits end with this revo

Welcome to RCTalk

Come join other RC enthusiasts! You'll be able to discuss, share and private message with other members of our community.

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

Bstrang6

RCTalk Rookie
Messages
18
Reaction score
0
RC Driving Style
Alright so I've got a 2.5 revo with a new Dynamite .19t, bout a half gallon of run time. Break in went great, not really any issues that I can recall, truck ran flawlessly through 5 tanks of nitro. So I put it away and come back to it the next day and it hasn't ran right since.

So far I have replaced the tank, fuel line, glow plug, pulled the motor apart and sealed the back plate, carb, and pinch bolt, printed the tuning flow chart, tried using that, printed the other tuning method I found on this web site and just can't get this darn truck to run. Its still acting very oddly.

Today I fire it up, let it idle for about 1 min, then start bashing, taking it easy at first. I ran about 75CC of gas ( one half tank ) through it and it was starting to act a little lean. So I pull in and richin the HSN after seeing temp readings above 300 degrees. run it around some more, pull it back in, still hot, so I keep adjusting the HSN out and nothing changes. So I shut it off and let it cool. I let it get to about 140 and goto start it again and it wont start. It doesn't seem to want to hold a prime, it cannot possibly have an air leak, I even sealed the P/S unit to the back plate. I'm at a loss. Is this motor just crap?
 
sounds like there an airleak some were...any breaks or cracks in the carb or anything like that
 
Thanks for the post, and no there's no cracks. I've started to notice a trend. I can get the car from dead cold, up and running easily, I can run for about 10 mins or so, but as soon as it gets down to a half tank, it starts leaning out. I notice temps raising so I back out the HSN, and notice that temps go up as the cars sitting there, so I richen the LSN so that the temp stays the same or goes down slightly at idle and go hot lap, come back and its creaping again.... I can see how I could have an air leak, or where it would be. Its a brand new tank, new lines, motors all sealed with rtv, brand new motor so the front bearing should be good... Its getting annoying lol.
 
Mid tank leaning is common. I have the same issue and am considering installing a secondary smaller pressure tank inline with the primary tank to stop this problem. There is one guy on here that did this with his revo and a lpr spec3 .28 engine. But I've lost the thread if i find it i will post a link to it.
 
Go to revo thread and find revo 4.6.

Here's a quick peak anyhow.
4c3c58be.jpg
 
U still get mid tank lean when the line is short. Mine was and it leaned out. The second tank stops in. Until the first tank goes empty anyway. But at least u get a full 150 cc of perfect run then if you gotta run it back to the car/home u can just baby it back off remainder of the second tank. Read the thread I made and I explained what I did to test it
 
Yeah i did cut all the excess line and go straight to carb from tank and it did help. It still leans out but only when almost empty now.
 
I also need to get a 150cc tank and get rid of this 125cc.
 
i tried something that seams to work. on my Jato. i put a check valve in the hose coming out of the muffler, next to it. holding the the pressure in the fuel tank. then put a tee fitting in that hose next to the fuel tank, plug the hole with out a hose on it, with JB-weld. then drill a hole in the JB-weld, .030-.040 inches. this will keep the pressure in the thank more even than the stock way. use a sullivan NO. S756 check valve.
 
Alright so I've got a 2.5 revo with a new Dynamite .19t, bout a half gallon of run time. Break in went great, not really any issues that I can recall, truck ran flawlessly through 5 tanks of nitro. So I put it away and come back to it the next day and it hasn't ran right since.

So far I have replaced the tank, fuel line, glow plug, pulled the motor apart and sealed the back plate, carb, and pinch bolt, printed the tuning flow chart, tried using that, printed the other tuning method I found on this web site and just can't get this darn truck to run. Its still acting very oddly.

Today I fire it up, let it idle for about 1 min, then start bashing, taking it easy at first. I ran about 75CC of gas ( one half tank ) through it and it was starting to act a little lean. So I pull in and richin the HSN after seeing temp readings above 300 degrees. run it around some more, pull it back in, still hot, so I keep adjusting the HSN out and nothing changes. So I shut it off and let it cool. I let it get to about 140 and goto start it again and it wont start. It doesn't seem to want to hold a prime, it cannot possibly have an air leak, I even sealed the P/S unit to the back plate. I'm at a loss. Is this motor just crap?
I’m going to stop at the dynamite 19 and tell u…if u have 170$ get the 28 big red, big blocks are child’s play now in em all mine have em, don’t cut arms or any j riggin neither, solid legit assembly with the 50$ traxxas mount and kit, linkage, reverse delete/foc, bellcrank and aluminum arm for bellcrank and throttle servo. Trans needs to be removed, cut exactly 3/8” of chassis off I. Front of trans. Mount /mock up, mark 4 holes, drill new mount holes leaving room to wiggle n mesh, reassemble the truck. Cut the inside right rear corner of the servo tray out, u will see when u mount engine the end of crank /clutch bell will rub. The cut section isn’t seen when lid back on servo box…..recommend a roto/spin or Sullivan tiger drive start setup. Center diff and rear brake recommend not absolutely necessary but be warned the 28 is a different animal. Back to why I say it. When the 19 came out I had a 3–4 year relationship with horizon hobby, they make dynamite/own it, the .19 had had 4 different re-releases, it’s flawed from the drawing board, back plate, one way bearing and starter shaft marry more than stepford wives together and they are known to crack entire factory cast lines outside block. I didn’t read anything more than the engine. I know their problems I’ve had 9, the 1 and ONLY ENGINE TO EVER BLOW, fail or die on me EVER, 7,different times, bearings were known flawed, rods would get out of balance and try to leave their channels, it was constantly grenading internally. Dynamite knife edges everything for massive compression numbers to keep their power and pinch. Of u don’t use heat gun from day 1 the engine is likely shot already anyway. 2 years later u may he able to start without em.
Alright so I've got a 2.5 revo with a new Dynamite .19t, bout a half gallon of run time. Break in went great, not really any issues that I can recall, truck ran flawlessly through 5 tanks of nitro. So I put it away and come back to it the next day and it hasn't ran right since.

So far I have replaced the tank, fuel line, glow plug, pulled the motor apart and sealed the back plate, carb, and pinch bolt, printed the tuning flow chart, tried using that, printed the other tuning method I found on this web site and just can't get this darn truck to run. Its still acting very oddly.

Today I fire it up, let it idle for about 1 min, then start bashing, taking it easy at first. I ran about 75CC of gas ( one half tank ) through it and it was starting to act a little lean. So I pull in and richin the HSN after seeing temp readings above 300 degrees. run it around some more, pull it back in, still hot, so I keep adjusting the HSN out and nothing changes. So I shut it off and let it cool. I let it get to about 140 and goto start it again and it wont start. It doesn't seem to want to hold a prime, it cannot possibly have an air leak, I even sealed the P/S unit to the back plate. I'm at a loss. Is this motor just crap?
How’s ur pinch? , sounds like bad air leak, back plate, carb, pinch bolt etc all Need seal with something called “Seal All” can of gas on front of tube, yellow red, resistant to anything petrol, this is the real deal. Seal those 3 areas, take hi speed housing off carb, blow through and clean out carb body, check o rings, check passages are clear, reassemble carb and reinstall and make sure the plug elements r glowing to the end of the plug. Otherwise it’s dead…recommend using heat gun to 125degrees minimum as the knife edging boosts compression massively, I even have to loosen glo plug on my big red and it’s got 2-1/2 gals through it looks brand new inside and out and will wheelie anything on 4 wheels that is remote controlled guaranteed….gearing compensates for the hi end power loss as it’s a big mill meant to distribute insane torque til about 23-25k rpm then fades, good CVEC pipe will even that out
Mid tank leaning is common. I have the same issue and am considering installing a secondary smaller pressure tank inline with the primary tank to stop this problem. There is one guy on here that did this with his revo and a lpr spec3 .28 engine. But I've lost the thread if i find it i will post a link to it.
I have 7 revos, 1 e revo, all 7 nitro have big blocks in em, been bb revo’s since before it was a thing haha, no mount and kit my 1st time and it showed, worked tho, kinda 🤣, now I have it to a science, the numbers are in my head if anyone needs the easy steps for the big block life. I’ll tell u , it’s literally 3-6 steps depending on setup
Also check the gasket on tank lid, fuel line, right hi speed housing and both gaskets help, and carb tight and clean; reset needless lo speed flush , hi speed about 3 turns out give or take, set idle gap and heat, start when to temp (175-200) tune for performance and reliability
Thanks for the post, and no there's no cracks. I've started to notice a trend. I can get the car from dead cold, up and running easily, I can run for about 10 mins or so, but as soon as it gets down to a half tank, it starts leaning out. I notice temps raising so I back out the HSN, and notice that temps go up as the cars sitting there, so I richen the LSN so that the temp stays the same or goes down slightly at idle and go hot lap, come back and its creaping again.... I can see how I could have an air leak, or where it would be. Its a brand new tank, new lines, motors all sealed with rtv, brand new motor so the front bearing should be good... Its getting annoying lol.
The issue is either the sleeve/piston r wearing out n when to temp have no pinch, or the tank lid, lines, hi speed housing/carb have a leak, head not tight. Bad shim, bad plug washer/ gasket or ur rtv didn’t hold up to the nitro which is 98% likely. Go to Walmart buy “seal all” it’s in a yellow tube with red gas can on the front of tube is resistant to everything 100%, it’s clear and is thick . About 11$ worth every available gram in there haha…check my 1st post, the engine was amazing when it ran, they die prematurely, love dynamite engines, they are all insane brutes. Beat em to death but the .19 is as flawed from the start sadly, I’ll see if I can find my block that cracked clear around entire crankcase where the cast molds met, still in 1pc but has a clean crack all around and it was still running 🤣
 
Last edited:

Similar threads

E
Replies
4
Views
178
easy rider
E
ccater1026
Replies
1
Views
535
Nitroman7888##
Nitroman7888##
ccater1026
Replies
15
Views
767
Nitroman7888##
Nitroman7888##
E
Replies
16
Views
338
easy rider
E
HDRIDER56
Replies
30
Views
1K
HDRIDER56
HDRIDER56
Back
Top