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3.3 wont go fast

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knall

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I have had this engine for a while..... I have tuned it a billion times.... I can usualy get her running pretty good.

No matter what I do....... the thing wont run fast.

Starts right up, seems fine. Idles OK, smoke level is good, can put around fine. But if I gice it WOT ( visualy inspected the carb, it is opening ) it bogs..... and wont gain speed..... eventualy stalls. I played with the needles for about 20 minutes, no help.

IT IS COLD outside, thats one thing I am concerned about.....

The fact that it starts and runs "WELL" makes me think its NOT the engine...... leaning towards the carb...... or the COLD.....

Like I said, I ran it and played with the settings for 20 minutes or so.... so I think its "warmed up" just wont go anywhere FAST.

Has anybody encountered this? does the COLD cause this?

I am ready to replace the engine AND carb (ebay $130) seems like the most cost efective solution.
 
knall said:
I have had this engine for a while..... I have tuned it a billion times.... I can usualy get her running pretty good.

No matter what I do....... the thing wont run fast.

Starts right up, seems fine. Idles OK, smoke level is good, can put around fine. But if I gice it WOT ( visualy inspected the carb, it is opening ) it bogs..... and wont gain speed..... eventualy stalls. I played with the needles for about 20 minutes, no help.

IT IS COLD outside, thats one thing I am concerned about.....

The fact that it starts and runs "WELL" makes me think its NOT the engine...... leaning towards the carb...... or the COLD.....

Like I said, I ran it and played with the settings for 20 minutes or so.... so I think its "warmed up" just wont go anywhere FAST.

Has anybody encountered this? does the COLD cause this?

I am ready to replace the engine AND carb (ebay $130) seems like the most cost efective solution.
Click to expand...

Depends on how cold it is. 20? If it's below 30 degrees farenheit then your gonna have trouble. The fuel can gel, plus on a trx you literally can't get the needle open far enough to match the amount of oxygen in the cold air. I've run my hsn over 7 turns out before and it just wouldn't let enough fuel in on a 15 degree day.
 
knall said:
I am ready to replace the engine AND carb (ebay $130) seems like the most cost efective solution.
Click to expand...

Instead of doing that, go to the traxxas site and do the Engine Replacement Plan, for like $85, you send them your engine and $85 and they send you a brand new 3.3!
 
savon said:
Instead of doing that, go to the traxxas site and do the Engine Replacement Plan, for like $85, you send them your engine and $85 and they send you a brand new 3.3!
Click to expand...


Its $110, and you gotta give em your old engine.

For $20 more I get to keep my engine. ( I think I just need a carb)

So if I get a NEW ENGINE and CARB, I will try the carb on my engine.... if that works...... I have a NEW spare3.3, if it doesn't work..... I allready have a new engine. See the logic?

Its in the 40's............. not worried about the fuel gellin.

My 2.5 seems to be runnin fine..... ( factory settings ) but the 3.3....... really has no top end .
 
Good idea, sorry. For some odd reason i always thought it was $85, my mistake.
 
There's one on ebay right now for about 120, delivered. It comes with a pull start which means it also has a owb. Now that's logic. Start your search with highest price first it's right there on the first page.
 
I found a 3.3 NEW on ebay, for $95 delivered. WITH an extra carb rebuild kit, AND extra ceramic crank bearings. NOW THATS LOGIC BABY!!!!!

DAMMIT!!!!!! I forgot about the one way bearing. LOL I know mine is on the way out....... some times the starter motor just goes WHING!!!!

Macguyver said:
maybe you are to lean on the HSN....cold weather needs to be more rich
Click to expand...


I was blowin raw fuel out the pipe at 4 turns out...... so I am runnin it lean. ....
How rich does it need to be when cold? Like an 1/8th of a turn? or like CRAZY rich?

I played with it quite a bit....... pretty sure I need a carb.
 
If it's 40 out then you would need as much as a full turn out (extra). It depends on your pipe, fuel and glow plug. That's on a motor with no air leaks or other problems. The colder air is more dense, more oxygen needs more fuel. If you're running a hot plug then try a medium, they work better in the cold. I think I saw that 3.3 on ebay....it was used?
 
Nope, shiny new in the box.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=160407445323&ssPageName=STRK:MEWNX:IT



I dont understand the glow plugs....... I thought they were just for STARTING..... they help with RUNNING????

2revo1maxx said:
If it's 40 out then you would need as much as a full turn out (extra). It depends on your pipe, fuel and glow plug. That's on a motor with no air leaks or other problems. The colder air is more dense, more oxygen needs more fuel. If you're running a hot plug then try a medium, they work better in the cold. I think I saw that 3.3 on ebay....it was used?
Click to expand...

4909 plastic pipe, traxxas %20 fuel, pretty sure I got the hottest cheapest plugs I could find.....

Top end performance realy hurt by dif plugs? If its running..... its burning fuel................. I figured the hotter the better.......
 
New with a side order of ceramics.....lucky. The glow plug is firing the fuel from start to finish. That little coil stays hot enough to touch off an explosion, combined with the friction created by compression. Hot plugs are like advancing the timing a little. Mediums will retard the timing a bit, and so on. When you're stuffing all that extra fuel/air mix in there on a cold day you want to back the timing off a little, with a medium or even a cold plug. On a 3.3 medium is all you need. If you're using trx plugs maybe try O'donnell #77's. Very good, reliable plugs. I like O'donnell red tops when it's hot out...hot plug. Also you might wanna try some better fuel. I use O'donnell 20%, but people here swear by Byron's fuel. I'm gonna try it this spring. 20-25% is all you want for a trx motor. If you switch fuels, you may notice less smoke from the exhaust. Oh yeah, break it in before you put in them bearings.
 
If your engine has good compression, replacing isn't the way to go. What's your temps? It may be sucking air from a leak once the rpm's start to climb. If you haven't sealed the engine, it's the next step. Check for fuel system leaks, too.
 

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