A little help with a LPR .28 getting right temp

[Gee]

I've been messing with this for a while and searched but really haven't found any answers. So here's my situation and hopefully I explain it well.

I got a XL with a LPR .28 on it geared 16/52 using 30% Fuel. I broke the engine in as per the manual. I've got probaly a gallon through it already. It doesn't seem to want to heat up. After seaching/reading about the LPR engines. I went back to using a sock on it for a while to finish breaking it in. Read it took longer then the usual amount of tanks to break these LPRs in.

When I lean out the HSN to tune it and try and get the temp closer to 200. I get to a point where it is to lean and bogs out at WOT. So I back the HSN off a bit and run it there but rarely seen the temp on it over 160 without the half sock on it. Plus after it's ran a while and if it dies (I don't run fast enough) it can be a real pia to start. It starts easy the first time for the day but get's tougher when it warm.

Any suggestions? Only experience I really have is with some trx 3.3 and an Axial .28

They were pretty easy to tune after break in. The axial likes to run hot but haven't ran into the problem of it being to lean at WOT and still below 200. Maybe the LPR likes to run cooler then most.

 

[abovelegit]

Not sure what to say, you could try switching fuels, my LRP is usually around 225 - 235. The fuel is the only difference I think would make a difference.

 

[Scrogg]

Lean the LSN, that's the key to the LRP. Engines run where they want too as far as temps. Good engines usually run cool like yours is doing. Richen the HSN back up to where the car is getting a decent top speed but still is slightly rich.
Then start leaning the LSN, the engine will start to sound cleaner and run better and start easier.
My LRP would not let me adjust the HSN until it had over a gallon on it. The only thing I touched on it during that time was the LSN and idle screw. 5 gallons later, it is still like a two gallon engine.

 

[Gee]

Thanks for the tips. I might have found a problem I was having. The carb wasn't seated all the way. Well it was after I sealed everything up but the pinch bolt loosened up and the ABS brakes I setup on the controller has a pumping action. It was slowly pulling the carb loose. I've sealed the carb and pinch bolt area again hopefully this will help a lot.

"Engines run where they want too as far as temps."
That makes sense and helps a lot. I am just going to try and get tuned for performance and not worry about the low temp.

 

[olds97_lss]

What's your temp gun and where are you reading the temp?

I have two LRP28S3's and both run pretty consistently around 230-240. During break-in, the temp wouldn't break 200 until about the 3rd 150cc tank. Then was at the end of the tank. Even with leaning it from factory.

What pipe are you running? What fuel tank? What oil content in the fuel and brand of fuel?

Is yours an LPR 28 or an LRP 28? Not sure if that's a typo or if you truly have a LPR engine.

I run 25% byrons w/11% oil. The HPI savage polished pipe was not liked by either LRP I had. Caused a muddy 1/3-2/3 throttle. Put a losi HT pipe on and all was much better, and quieter by a large margin.

 

[Gee]

Duratrax flashpoint temp gun. I place the pointer into the cooling head pointing at the GP press and release before I remove it from the cooling head. I have a JP-3 on it. Still have the stock tank. Byrons 30/11 and LRP Z28R Spec 3. MC-9 or Odonnel 99 of late. Gearing is now 47/18 after a probelm with the stock spur and a coulple of stripped out clutch bells. Currently got a set of 6" 40 series Mashers tires.

I am starting to believe I got a hold of a bad luck RC. One of those ones that no matter where it goes or who owns it. Bad luck will follow it. My first Jato was a voodoo doll of bad luck. This one has been nothing but a pia since I got it. Almost every time I have gone to take it out for a run. Something has gone wrong with it. That either stops me from taking it or lugging the beast a mile back to the house. The other times it was all spent trying to tune it or make it controllable. It was a squirly pig for some reason when I got it. Would just want to take off left or right with no consistency on which way it was going to go. I haven't given up on it yet, but boy I am getting close to pawning this puppy off (to someone far far away from me) and getting me a new XL and not a roller. Today it was a clutch shoe, yesterday was the carb needing sealed, the other day was steering servo, that day before that was stripped clutch bells, then the differential, then the bulkhead, and another differential, etc. The LHS doesn't stock much for the savage so waiting on parts keeps me entertained when it's down. I have several other rc that want to frustrate me but this one has been taking up all my time.

I've seen the potential with this engine, it was brief but promissing. That was the one day I had fun with it. Like that one shot out of hundred in your round of gold. The one that makes you go back and put yourself through another 18 holes of frustration. I just can't find that sweet spot again. Easy to get yourself confused reading threads about what you're working on and next thing your are trying three different methods you read about to fix it. All at the same time, and you have no idea what you are doing or how you got it so screwed up. This time......

I feel better now. Thanks.

 

[frickenjoey]

Wow you broke a Savage bulkhead? I have never done that and I have done some crazy stuff with it too. That is impressive. I am glad to see you geared it up a tiny bit I thought that was a bit low to start with. My LRPs (have 2) Like to run around the 240-250 range. In my truggy it is a tiny bit cooler than the Savage because the Jammin is not as heavy. Yeah when you spin the carb around you do have to be sure you get it sealed back well and tightened down. Sorry to hear you are having such bad luck with your Savage.

 

[Scrogg]

You have a big heavy tire, and your gearing is too high. Drop to 17/47 with those tires. The LRP is a revver, it will be faster all around with the right gearing and it will run cooler. That engine tunes best on the McCoy 59's, at least in my climate.

 

[Gee]

Well I didn't really break the bulk head. When I got the roller in I didn't realize one of the bearing in the bulkhead was bad. Ended up making the place where the bearing ride larger and that what started the differential problems. LHS didn't have the XL bulkhead so I bought the older style to hold me over until the XL BH arrived. This XL has been one heck of an adventure. On the bright side I do know how to properly shim a differential now.


The 18t was the best option the LHS had in my desperation I snagged it up. I appreciate you guys chiming in and offering some help. I ordered a 15t from amain in anticipation of the Cen differential mod. I just got 9t bevel gears in today. So everything is here and next differential problem I have I will be installing them. What would you recommend for a CB and the 47t spur once the cen diffs are installed?

I was wondering about the glow plugs. I did some searching and read that the MC-59 was a hot plug for low to med nitro fuels. I had some 59's and thought that might have been one of the contributing factors because I run the 30%. That's when I went to the MC-9 and OD 99. I've used the MC-59 before and they seemed to work fine.

It was another fun day with this rc. Started out promissing. I was on the ae site looking for answers and download the manual for the engine. It's factory defaults were different then the one in the manaul that came in the box. The box has 3.75 for both the H and L. The downloaded manual had H 3.5 and the L 2.5. Gave me hope again. Thought I had the wrong factory setting all this time. So I put everything back together after replaceing the CB bearings and installing the tiger drive I had for it. Started right up but was really rich. Had to really feather it to get it going. Ran it around the yard a bit and things were looking up. After a short nap. I gathered up everything for a walk with the rc. Started up easy and I warmed it up around the yard. Then the Hitec 5998tg I just put in it died on me. The 5955tg I had in it previously top case broke (part of the saga). Got several of the same type Hitecs in different rcs and this is the first one to ever give me a problem. It figures it would be the servo in the XL. I stole the servo out of my emaxx and proceded for my walk. Got a ways from the house (and neighbors) and the nightmare started all over again. I spent too much time on my knees in the gravel this evening and decided I'm done with this lrp. Haven't been this frustrated with an engine since my Kyosho gx27 or what ever it was. The lrp will be sitting in the same box with it. Going to get the Axial .32 tomorrow. The Axial .28 I have in my Kyosho STRR has been an excellent engine. It was easy to break in, has helds a tune great, and flat out makes that truggy get up and go. Hopefully the .32 will be the same and have enough power for the XL.

Are there any good 17mm hex adapeters for the XL? All I find are the semi cheesy stock ones, the adapters for the X conversions, and 40.00 Integy ones. I guess I could drill out the end of the traxxas ones to make them fit onto the larger axle or just fork out the cash for the integy ones.

 

[Scrogg]

MC-59's work perfect in that engine, but the cooler plugs will give you more top end and better fuel mileage.
The LRP takes a full gallon to break in, you are wasting money buying an Axial .32. It's a much poorer quality engine than the LRP.
I have no experience with the CEN diff mod. I have always used stock Savage ring and pinions. Shimmed correctly with good bearings they will snap dogbones all day long and not hurt the diff. When you buy something used, tear it aprt and go through it. A few dollars on bearings and a little extra time would have saved you a lot of money and hassle.
HPI needs to quit using 10X16X5 diff outdrive bearings and go to 8X16X5 bearings like the rest of the 1/8th scale world. Those bearings are too small for the abuse a Savage takes.
Also they need to make a slipper clutch like the Revo's. That cheesy sticky pad on the spur is not adequate. It makes too much heat if you set it to slip like it should.

 

[olds97_lss]

Are there any good 17mm hex adapeters for the XL? All I find are the semi cheesy stock ones, the adapters for the X conversions, and 40.00 Integy ones. I guess I could drill out the end of the traxxas ones to make them fit onto the larger axle or just fork out the cash for the integy ones.

I just upgraded mine to the "cheesy" stock ones. lol

With the LRP in there, 14mm hex's wouldn't be lasting real long. Now I just need to fork over the dough for new rims/tires and adapters for my aftershock. Burned out 2 hex's last year with it and cracked 2 rims. Never had that problem until I got the LRP. Stupid power...

 

[Gee]

The axial isn't even a drop in the bucket when it comes to all the money I've "wasted" in this hobby. Got a box of new parts that were bought but just didn't seem to work out. You've all probably got those boxes of parts also. Almost enought to make a melting pot roller. Then there's the RCs that are collecting dust, controllers that looked cool, and tires, heck my back room looks like Les Schwab tire. Neighbors are lining up for the for the free beef. lol

I picked the .32 up earlier today. One plus is I have an spare pullstart for the .28 now. If this one does as well as the Axial .28 I'll be happy for now. I would of payed another 100 just to stop the insanity (frustration) with the LPR. I want to have some fun with this Savage. Someday I will be going through all the wasted money parts and pull the lpr back out and give it another go. Anything special I should do it before it get put away. Tear it down and lube it? Reseal it?

You UPGRADED?... to the cheesy stock one!?!?! lol Actaully, I thought they were a great idea. I have a pet peeve about woobles, loose wheels, steering, etc. They did pretty well with the tera pins, They just weren't cutting it on the 40s mashers. I have the mashers installed on some 17mm axial bead locks but I think I will just get some lighter 23mm dish or wabash rims for the mashers. The mashers tread lasts a long time so I'll use the axial bead locks for bow ties, etc. The kind that the tread wears out fast. I had some 23mm integy hexes for the Jato and they came with a black O ring. I am using the nuts off them but not sure if the O ring is suppose to go between the rim and hex or betwen the rim and nut. Any idea or thought which way would be best?

 

[olds97_lss]

Have no idea. Didn't notice any wobbling, but I'm using standard size RPM revolver wheels with old school savage rubber.

If you have any interest in selling the LRP, I'd bite depending on the price. Can't hurt having spare parts if it's a dud. Spare carb and cooling head are always nice to have in the bucket.

 

[Gee]

I thought long and hard about selling it to you olds but thought I would mess with it some more. I removed the flywheel and checked it again for leaks by blowing bubbles. I got some bubbles coming out of the front bearing. Should there be no air/bubbles at all coming from around the shaft/bearing area? The rest of the engine is sealed up w/ no leaks.

 

[olds97_lss]

Well, bearings really aren't air tight. Sure, they may be for a little bit when first new, but as the rubber seal wears a bit from running, a bit of air will make it through and a bit of oil will seep out. If it's excessive, then it would pose a problem. Like a pool of fuel under the engine or a lot of air blowing through.

Might be worth trying to replace it though. Bearings aren't too expensive. Not sure what bearing brand I'd go with. Probably a boca engine specific bearing.

Found a crankcase w/bearings new on ebay for $38 shipped:
Ebay Link
Item: 270393143080

 

[Gee]

Thanks for the link. I will probaly pick one up if the problems persist with the LRP. The Axial .32 that I put in the XL is running great. I just put the cen ring and pinion on the xl cup on Friday. Yesterday was the first full day of bashing with the XL that something didn't go wrong. Finally, some fun! Now I can say great truck!

I pull the axial .28 from my truggy and tested it for leaks. It started winding up while idling. Found it has a much larger leak around the front bearing then the LRP did. It has 6 or 7 gallons through it. Not really sure never paid much attention to that before. Was my first nitro engine. I put the LRP into my STRR yesterday to give it another try. I used the FS that I found in the downloaded LRP manual. It started up fine and ran it for a tank and a half. It was around 220 or so and when it died. I couldn't get it started again and could hear the fuel boiling in the carb when I blew through the exhaust fuel line. I put a new battery in my temp gauge but it still may be off.

I could try somewhere between the FS in the printed manual of 3.75 H and L and the downloaded manual that has 3.5 H and 2.5 L. Thoughts on the FS for the LRP?