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RS4 wont run

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rs4evo

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well, I'm new to nitro rc and i just got a rs43 evo. right from the beginning the thing just wont run. it would start up and run if i gave it about 3/4 throttle but would eventually just die. i went through this for 2 days tuning back and forth on the carb with no success till finally my glow plug quit. so went to the lhs and got 2 mccoy mc-9 plugs...then my engine wouldnt start at all so i started researching the plugs and such, and read that the mc-9 is a cold plug meant for 30% or higher nitro. is this true?..I'm running 20%. today i took the carb off and lubed the o rings for a better seal and zip tied the fuel line. would the the mc-9 plug cause it not to start?..what plug should i use?
 
I have typically used the MC-59 and it's worked well for me.
Now, about your problems. Usually. HPI engines are pretty reliable and run well. Here's what I'd suggest to do first. Reset the HSN and LSN back to factory settings. They should be outlined in your manual. And be sure to check your idle setting. When you have the radio on, push full brakes. The carb should remain open about 1mm.
If those things check out, double check for pinholes in the fuel or pressure lines. Make sure all is hooked up right. If it still ain't working we'll have to poke away at some other things.
 
ok, well, my manual says flush on the LSN and 3 turns out on the HSN. tried that, no luck. The instruction sheet on HPI's website for the T-15 engine says flush on the HSN and flush on the LSN. Tried that, still nothing. I noticed that sometimes air bubbles will be pushed into the fuel line from the carb after i stop cranking. So, i pulled the fuel tank, no leaks in it or the lines. Now I'm working on pulling the motor out and I'll pull the backplate and carb and seal em with silicone, see if that solves it. would the mc-9 plug cause the motor not to run at all on 20%?
 
I have used the MC-9 but I use 30%. When I had the original HPI RS4 RTR3 I used the MC-59 on the old 15FE dog. It ran fine for me.
 
Thank you guys for your help and quick replies. I've had this car since christmas last year and I'm just now getting to try and play around with it, but i've been fighting to get it running for the last week. It's frustrating but I've always worked on real cars so i like the challenge. So, the air bubbles in the fuel line, does that mean i definitely have a leak or is this sometimes normal? Oh and yay, i stripped one of the cheapo engine scews :whack: , any idea on how to get that out so i can get the motor out?
 
rs4evo said:
Thank you guys for your help and quick replies. I've had this car since christmas last year and I'm just now getting to try and play around with it, but i've been fighting to get it running for the last week. It's frustrating but I've always worked on real cars so i like the challenge. So, the air bubbles in the fuel line, does that mean i definitely have a leak or is this sometimes normal? Oh and yay, i stripped one of the cheapo engine scews :whack: , any idea on how to get that out so i can get the motor out?
Which screw?

The bubbles you get are fine. Do you have the grommets between the tank and the mounting posts?
 
rs4evo said:
ok, well, my manual says flush on the LSN and 3 turns out on the HSN. tried that, no luck. The instruction sheet on HPI's website for the T-15 engine says flush on the HSN and flush on the LSN. Tried that, still nothing. I noticed that sometimes air bubbles will be pushed into the fuel line from the carb after i stop cranking. So, i pulled the fuel tank, no leaks in it or the lines. Now I'm working on pulling the motor out and I'll pull the backplate and carb and seal em with silicone, see if that solves it. would the mc-9 plug cause the motor not to run at all on 20%?


Go with the MC-59 That's a hotter plug to run with the 20%..Are you priming before you try to start it. Hold your finger over exaust hole and pull 2-3 times looking for the fuel to enter carb, and then start. Make sure you got a glow ignigter that is fully charged. Make sure carb is at 1mm opening. I think the HPI engines are rich out of the factory so leaning is gonna be needed for sure.
Let us know how it's going.
 
Which screw?

One of the phillips ones on the bottom that actually attaches the motor to the chassis.

Ok, well, as soon as i figure out how to get this screw out, ill take the motor apart and seal everything up with silicone for good measure, then i guess ill have to wait till i can get some new plugs..again...damn this thing
What do you guys think of a stainless screw kit?..wise investment? also i noticed with the reciever, servos, and exhaust off that where was a lot of chassis flex. i know its a lot stiffer with all that stuff attached, but this leads me to believe that a CF upper deck would also be a good upgrade?..thanks again
 
rs4evo said:
One of the phillips ones on the bottom that actually attaches the motor to the chassis.

Ok, well, as soon as i figure out how to get this screw out, ill take the motor apart and seal everything up with silicone for good measure, then i guess ill have to wait till i can get some new plugs..again...damn this thing
What do you guys think of a stainless screw kit?..wise investment? also i noticed with the reciever, servos, and exhaust off that where was a lot of chassis flex. i know its a lot stiffer with all that stuff attached, but this leads me to believe that a CF upper deck would also be a good upgrade?..thanks again

Use a dremel with a cutting wheel and dremel a slot on the screw. Then use a flat head and get that lil guy out.

Screw kit I would try a Hexcrews kit. I am still going through my rebuild on my Storm and they are kick ass. I tried RCsrewz and they flat out suck. Too soft of an alloy.

As far as your flex. you will see flex with that gear off more. What you should be looking at is when all the gear is on. A CF would be nice but for bashing... not necessary IMO!
 
Ok, well, cut a slot in the screw and it stripped that out too. sucker was in there good. so i ended up having to drill the head of the screw off, and ill have to get my dad to bring home a screw extractor from work. i took the carb off and sure enough, one of the o-rings was torn so i siliconed that all up. so tomorrow after it dries i guess ill try again and see if it will run on the mc-9 plug. if not ill just have to wait till i get a hotter plug. thanks again guys
 
man i wish i had thought of the torch thing BEFORE i stripped the screw..lol. oh well. i also pulled the rotostart and backplate off and siliconed all that, there should be no leaks at all on this puppy!..i dont know when ill be able to get the new glow plugs, but I'm gonna go with the mc-59. seems thats what most people are using. if this thing doesn't run after all this i'll prolly have to take it up to the lhs and see if they can work it out.
 
ok, well, i was studying up on my car cuz i have to wait till later to get some glow plugs and i was looking at one of the exploded views of the engine, and i noticed 2 pieces that i did not see when i had my engine apart. the two pieces circled in the picture were missing. and i put silicone on the places indicated. so my questions are, what would be the effects of these pieces being missing, and would the silicone i put in solve any problem caused?.. or do i need to get ahold of these parts somehow?. thanks for the help. i really hope this isnt a big problem, but i think it may be, they look like seals to me. no seals=no good
 
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they are o-rings that help to seal everything off, can't tell you much more. With the starting thing, when i first started my RS4 i had the HSN at 2 turns out also I had a similar problem with it dying around 3/4 throttle and I had to bring it to the lhs and have them look at it and it turns out that if it never makes it to 2nd gear before dying try and set the shift time lower and this solved my problem
 
ok, sorry, i was wrong, i was just looking at the diagram wrong, i pulled the motor apart again and the o-rings are in place as they should be, no worries. tomorrow new glow plugs and hopefully the first run:banana:
 
alright. i got me a couple of MC-59 glow plugs, and she fired right up no problem. got to actually run it around a little. i've got about 3 tanks through it on the breakin and I'm starting to lean it out a little at a time. but my glow ignitor died. so thats all for tonight. thanks for your help guys, i dont know if i ever would have got this thing running.
 
dude i got the same car, run 25% traxxas nitro fuel it's the blue kind promise you it will work
 
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