LRP .28 bogging down at low temps?

[dj_sparky]

I'm running an LRP .28 in a savage, and at low temps (158 fahrenheit.), I can't tune in the HSN higher without it bogging down to a stop. It runs fine at this limit, wheelies no problem at all (Almost a problem.), but why can't I tune it any higher? Is this a LSN/HSN combination issue? I would think that I could tune it higher when max temp is only 158 fahrenheit. I can't even run it lean. It puts out a lot of smoke etc, but I can't even lean it. What's up with that?

Is this a LSN issue, or could it be that it's not finished its break in yet? (I bought it used.)

 

[olds97_lss]

Where are you checking the temp? How much fuel is through the engine?

I'd check to make sure your temp gun is accurate... do you have a spare aluminum part laying around that you could boil then check the temp of? If so, I'd try that to make sure your temp gun shows around 212F

 

[Racer 1966]

Dude at 158 you're way to cold for efficient combustion. You need to lean it down and bring the temps up over 200. Which direction are you turning the needles? Clockwise is leaner.

 

[dj_sparky]

It's accurate, I use it on several other cars with accurate readings (Most cars are @ 200ish or more. Whatever is best for the engine). When I try to lean it further in, it just bogs down and dies. This is at 158 fahrenheit. It's supposed to be broken in and then some. But it's running slightly rich even, and I can't tune it further in, let alone run it lean. (And yes I know which way to turn.)

Could it be that I need to turn the LSN further in before I can turn the HSN further in or something? Or could it have something to do with it not being fully broken in yet? I don't understand this problem. Turning the HSN (Yes, clockwise) further in, when I'm at 158 fahrenheit, bogs it down and kills it. It pulls wheelies and is pretty wild, but it's still cold and there's room for much more power, yet it just bogs down..

I'm running a Dynamite Platinum 053 pipe btw.

 

[dj_sparky]

Took it out again, and when I turned the LSN out I could lean in the HSN a bit more. I guess it's just hard to tune it, and I have to find the best match for them both?

Even so, at 158 or lower it bogged down and died at top speed after a lot of fiddling with the LSN and HSN. Could this have something to do with the LSN? What's up with it? Could there be something wrong or?

It runs perfectly, but it just bogs down at certain HSN/LSN settings. Is there a problem with the engine, or is it simply a tuning issue?

 

[olds97_lss]

I have two LRP28S3's and neither of them run below 200F. They did for the first couple of tanks of break-in, but once they hit 200F, they never drop below it with typical running. Mine both run around 220-240 all day long.

Just seems really strange that yours is temping that cold.

 

[dj_sparky]

Turns out the LSN was 4 turns out or so (And I don't think I ever had it below 3.5 turns out or so.), and factory settings are 3.75 (Which is extremely rich.). Will try again later on with it set at lower.

And according to the previous owner, he said around 1 liter (Which is like.. 0.35 gallons or something.) after break-in, but I don't know his definition of a break in. I've heard that LRP's don't really come around until after several gallons, so.. maybe that has something to do with it.

 

[dj_sparky]

Turned out the HSN was already set way in, so that accounts for the bogging when I tried to turn it even further in. I managed to set the HSN right @ the limit before bogging, and the LSN to a perfect "pinch test". Now it runs fine, and the temps are up there at normal range.

But still, why doesn't it allow me to run it lean? There's a thick trail of smoke, along with fine temperature ranges, but whenever I try to lean the HSN in a bit more it bogs down and dies at higher speeds. (Same with LSN at lower speeds.)

Previous owner informed me that the engine has only been through about 1.2 gallons of nitro. I've heard that LRP engines can take up to 4 gallons before they really perform well or before they are finally "broken in". Is this true?

 

[Rolex]

If it runs fine, leave it there. There is NO reason to lean it past the position that it runs good. Tuning is all about getting the engine to run where it runs the best, not where YOU want it to be, especially during break in.
If you're not sure that it's been broken in properly yet, don't be looking to lean it any more.

 

[dj_sparky]

I agree. It runs fine, wheelies on command like 80-90% of the time, wheelies right on its head despite a wheelie bar, so there's a lot of power. But I'm wondering why I can't run it lean, when it's supposed to be broken in - 1.2 gallons through it. Could it be that it's not broken in yet, or what? I've never encountered a nitro engine that doesn't allow me to run it lean. This one bogs down instead of no trail smoke and extremely lean/hot. Why? It's a very nice safeguard hehe, but I don't think that's normal. It's at the very limit of both LSN and HSN, even 1/8 turns in and it starts bogging again (Either at low speed for LSN, or at high speed for HSN of course.). Even though it's not a good thing, I should be able to tune it in leaner or no smoke, etc. Yet I can't.

Could there be some dirt in the carb or whatever? Or, again, not broken in yet? Since I've heard that LRP's don't really come around until after a few gallons. Bogging down like this is a classic sign of tuning at break-in, right?

This bogging thing didn't start happening until I installed the Dynamite Platinum 053 mid-range pipe, which tons of people have recommended for the LRP. But then again, I only barely touched the HSN with the previous standard pipe (Didn't touch the LSN at all.).

It's running fine though, I'm just curious why this is happening. By the way, is 80-90% wheelie "rate" normal for an LRP engine on a Savage X? Or should it be able to pull wheelies 100% of the time from a standstill? (Using this as an example of power comparison.) I think it has stock clutch and spur gears. Like, does it ever happen that your car with an LRP doesn't pull a wheelie from a standstill?

 

[Scrogg]

Too much mechanical pinch. The LRP will not let you lean it much until it's ready. If it runs great @ 180-200F, leave it be. Once the pinch relaxes around 1-1/2 gallons, it will let you lean the top some more. At that point I HIGHLY suggest checking the bearings and con rod. Replace anything with slop.

 

[RoosterXp]

Too much mechanical pinch. The LRP will not let you lean it much until it's ready. If it runs great @ 180-200F, leave it be. Once the pinch relaxes around 1-1/2 gallons, it will let you lean the top some more. At that point I HIGHLY suggest checking the bearings and con rod. Replace anything with slop.

I totally agree!! might want to try fattening up the HS needle and leaning the low speed needle.. this might help?