LRP 32120 User manual

1
3
2
4
Z Z . 21C
CERAMIC
user guide
ORDER#:
32120
2.92 HP
40.000 RPM
MA00232 © LRP electronic GmbH 2011
7. carburetor
5. exhaust system
8. run-in
2. fuel
6. head clearance
1. specification
3. airfilter
4. glowplug
Engine size .21 (3.49ccm)
Exhaust Rear
Bore 16.30mm
Stroke 16.80mm
Liner ABC
Number of ports 3+1 (3x transfer-, 1x exhaust-port)
Main bearing Ceramic
Crankshaft 14.0mm / DLC coating / precision balanced / with silicone insert
Crankcase Black XTEC C6 .21 Heavy-Duty Competition
Piston Specially lightened, high-silicium alloy
Connecting Rod Oversized, knife-edge shaped, extra strong aluminium,
double bushings
Glowplug Hot Turbo style, LRP Turbo WT3 (No. 35135) included
Carburetor XTEC thermal protected WorksTeam carburetor.
Aluminium 6.0, 6.5 and 7.0mm inserts included.
Power Output* 2.92 HP
Max. RPM* 40.000
Weight 345g
*Figures may vary depending on used fuel, exhaust system and tuning.
Never use regular gasoline or airplane fuel. Use fresh 2-stroke model car fuel only! We recom-
mend using our line of LRP Energy Power fuels (No. 35711: 25% 1L / No. 35731: 25% 3,5L). For
the LRP ZZ.21C Ceramic engine, we recommend a fuel with 25% nitro. Never exceed 36% nitro.
A higher nitro content will decrease your engine‘s lifetime.
A good airfilter is very important for the life of your engine. Never run without an airfilter, as
quick and permanent damage will result! Don’t forget to impregnate the airfilter with a suitable
oil before usage. Carefully clean the airfilter at least after every tenth tank. Replace the airfilter
every 3 litres (~1 gallon) of usage.
We recommend the use of our LRP Hi-Flow 2-Stage oval airfilter (No. 36565) together with our
LRP Hi-Flow airfilter oil (No. 36590).
Use only Turbo style glow-plugs (also known as conical style plugs) for this engine. We recom-
mend using our line of high-quality LRP Platinum / Iridium WorksTeam glowplugs (No. 35135
- No. 35145, availabe as WT3 and WT4). Check them frequently and never run with worn-out or
old glow-plugs since they could damage your engine. They turn dull when your engine was too
lean and should be replaced. They should stay bright like chrome. If the glowplugs wear out too
fast, an additional 0.1mm shim between burnroom and liner is recommended. Whenever you
have trouble with the engine stalling for no reason, replace the glow-plug first!
TIP: Our LRP team always uses a LRP Platinum / Iridium WorksTeam WT3 (No. 35135) plug
for the LRP ZZ.21C Ceramic engine.
Dear Customer,
thank you for your trust in this LRP product. By purchasing a LRP nitro engine, you have chosen
a high-performance and highly sophisticated product, which doesn´t make any compromise
between maximum performance and easy tuneability. We hope you enjoy your new engine.
Please read the following instructions carefully before you start using your LRP ZZ.21C Ceramic
engine. This user guide contains important notes for the installation, the safety, the use and the
maintenance of this product. Thus protecting yourself and avoid damages of the product.
Proceed according to the user guide in order to understand your LRP ZZ.21C Ceramic engine
better. Please take your time as you will have much more joy with your product if you know it
exactly.
This user manual shall be kept in a safe place. If another customer is using this product, this
manual has to be handed out together with it.
Never run without a pipe since this will cause excessive overheating and may damage your
engine. A good pipe has a very huge effect on the performance of a 2-stroke engine. For the
LRP ZZ.21C Ceramic engine, we recommend using our high-quality LRP Enduro-46 1/8 Off-Road
Exhaust System (No. 36250) for maximum performance.
We recommend a real head clearance between piston and burnroom of about 0.60-0.70mm
(0.024-0.027“) or more, when the piston is at Top Dead Center. The real head clearance can be
calculated as follows:
Real head clearance = Thickness of head shims + 0.25mm*
We suggest to start with 0.35mm (0.014“) shims underneath the combustion chamber. You may
want to adjust the shims depending on nitro-content (see table) or track layout. Large tracks may
require an extra 0.10mm (0.004“) shim to reach higher topspeed and improved fuel consumption,
but this will decrease acceleration slightly.
Nitro content 16% 20% 25% 30%
Real head clearance 0.60mm / 0.024“ 0.65mm / 0.025“ 0.70mm / 0.027“ 0.80mm / 0.031“
Head shims 0.35mm / 0.014“ 0.40mm / 0.015“ 0.45mm / 0.016“ 0.55mm / 0.022“
* (that‘s due to the internal construction of the engine and the compression of the head shims, when the cooling
head is mounted)
The factory settings of the engine are as following and are a good starting point for you, if you
are not satisfied with your carburetor settings. Turn in the needles completely (Caution: Do not
overtighten them!) and loosen them the required number of turns again:
Idle screw (#1):
Adjusts the air flow when carburetor is fully
closed. Turn CW for higher idle-speed and CCW
for lower idle-speed. Should be open approx.
0.5mm.
Mid range needle (#2):
Adjusts the mid/low-speed flow rate of the fuel.
Turn CW for leaner and CCW for richer setting.
Main speed needle (#3):
Adjusts the main flow rate of the fuel (when the throttle is opened
significantly). Turn CW for leaner and CCW for richer setting.
Third needle (#4):
Should always stay in the factory setting exactly flush with the carburetor body and should not
be changed.
Carburetor venturi inserts:
In order to affect the fuel/air mixture, you can use different venturi inserts on this carburetor.
These are to finetune your engine to different track layouts. There are three different venturis
coming with the engine: 7.0mm, 6.5mm and 6.0mm.
- 7.0mm has the most power, 6.0mm has the best fuel mileage.
Proper run-in of the engine is a very important step in ensuring that you get the highest perfor-
mance and lifetime of your engine. Take your time for proper run-in. Do not use run-in benches,
but use your car for run-in. Use the same fuel as you will be using for the life of the engine.
Special run-in fuel is not needed. If your engine doesn’t start easily you may try loosen the glow-
plug by ½-turn to decompress the engine and try again. Don’t forget to tighten the glow-plug
again once the engine started!
Procedure:
• Starttheengineandsetthe main-needlevery rich,i.e.excessivesmokecoming from the
muffler. The factory settings are a good starting point.
• Lettheengineidlefor2minsrsttowarmitup.
• Nowstartdrivingyourcar,itwillbeslowandsluggish,butthisisanimportantstep.
• Donotallowtheenginetorev-uptoohigh,runtheengineathalfspeedonthestraightaway.
• Theengineshouldnotbetoocoldandnottoohotduringrun-in,70-80°C(160-180°F)isper-
fect.
• Lettheenginecooldownfor15minsaftereachtankduringtherun-inperiod.
• Werecommenddoingsofor10tanksoffuelbeforeyoustarttuningyourengine.
LRP electronic GmbH
Wilhelm-Enssle-Str. 132-134
73630 Remshalden
Germany
in f o@ LR P.cc
www.LRP.cc
•Mainspeedneedle(#3): 3 1/4 turns
•Midrangeneedle(#2): 2 1/2 turns (starting from the needle being flush with the ball
link)
•Thirdneedle(#4): Exactly flush with the carburetor body

12. trouble shooting guide
9. tuning
10. after run
11. maintenance
repair procedures /
limited warranty
All products from LRP electronic GmbH (hereinafter called “LRP”) are manufactured according
to the highest quality standards. LRP guarantees this product to be free from defects in materi-
als or workmanship for 90 days (non-european countris only) from the original date of purchase
verified by sales receipt. This limited warranty doesn’t cover defects, which are a result of
misuse, improper maintenance, outside interference or mechanical damage. This applies among
other things on:
 • Enginedisassemblybycustomer
 • Anymodicationoftheenginedonebythecustomer
 • Rustinsidetheengine
 • Dustordirtinsidetheengine
 • Damagedengineduetoglowplugfailure
 • Overheating
 • Scratchesinsidetheenginecausedbydirtordust
 • Waterinfuel
 • Wrongbreak-inprocedure
 • Damagedpistonduetopistonstopdevices
 • Damagedcylinderexhaustportduetopistonstopdevices
 • Breakagesathighrpmwithoutengineload
To eliminate all other possibilities or improper handling, first check all other components in your
model and the trouble shooting guide, if available, before you send in this product for repair.
If products are sent in for repair, which do operate perfectly, we have to charge a service fee
according to our pricelist.
With sending in this product, the customer has to advise LRP if the product should be repaired
in either case. If there is neither a warranty nor guarantee claim, the inspection of the product
and the repairs, if necessary, in either case will be charged with a fee at the customers expense
according to our price list. A proof of purchase including date of purchase needs to be included.
Otherwise, no warranty can be granted. For quick repair- and return service, add your address
and detailed description of the malfunction.
If LRP no longer manufactures a returned defective product and we are unable to service it,
we shall provide you with a product that has at least the same value from one of the successor
series.
The specifications like weight, size and others should be seen as guide values. Due to ongoing
technical improvements, which are done in the interest of the product, LRP does not take any
responsibility for the accuracy of these specs.
LRP-Distributor-Service:
 • Packageyourproductcarefullyandincludesalesreceiptanddetaileddescriptionofmal-
function.
 • SendparceltoyournationalLRPdistributor.
 • Distributorrepairsorexchangestheproduct.
 • ShipmentbacktoyouusuallybyCOD(cashondelivery),butthisissubjecttoyournational
LRP distributor‘s general policy.
It never hurts to have the mixture too rich, but NEVER let the mixture get too lean. Always tune
from rich to lean. If in doubt, richen it up first! Never try to tune a cold engine, run 2-3 minutes to
get the engine up to running temperature before doing any adjustments!
Basic tuning procedure is as follows:
1. Set the engine’s idle speed up slightly higher than normal.
2. Start tuning your engine with the settings too rich.
3. Always tune main-speed needle (top-end) first.
4. Tune mid-range needle next.
5. Reset idle speed screw.
Procedure:
1. Set the idle speed so your engine doesn’t stall (slightly higher then normal).
2. Go to the track with the main-needle set too rich, there should be heavy smoke coming from
the muffler now.
3. Tune the engine by leaning the main-needle 1/8 turn at a time (turn clockwise).
- Your goal will be that the engine will just reach maximum RPM on the straightaway.
- Open the main-needle again by an 1/8 turn (turn counter-clockwise) when you have reached
thatpoint.Thisshouldbetheperfectsettingforthemain-needle.Temperatureof95-105°C
(200-225°F).
- If the main-needle is set too lean, the engine will overheat and will not accelerate smoothly.
If this happens, immediately stop the engine and richen the main-needle (counterclock-
wise) 1/4 turn before a new attempt.
4. Adjust the mid-range needle now. Run 3 full laps, stop the car near you and let it idle for
5secs. „Push off“. It should have slightly richened up (idle rpm gets lower), but still accelera-
te quickly. If it died before the 5secs, check the following:
- If the rpm constantly decreases and finally the engine stops, the mid-range needle is too
rich.
- If the idle-speed increases during idle, the mid-range needle is too lean.
5. You may have to re-adjust the idle-speed now. If it idles too high, the clutch may not release
completely and you will lose „snap“ off the corners. If it idles too low, it may stall at the start,
or at the end of the straightaway when you release the throttle.
Ways to measure the engine temperature:
• Temperaturegaugemethod(recommended):Pullinquicklyandimmediatelytakeatempera-
ture reading. Place the gauge directly over the engine pointed at the glow plug.
• Spitmethod:Pullinquicklyandimmediatelyputsomespitontheengine’shead.Thespittle
should just slowly boil off (2-3secs). It should not dance around as if it were on a hot griddle,
nor should it lay there and steam.
Use after-run oil to keep everything lubricated after you have finished your day. After-run oil
helps for an easy start the next time and protects your internals against rust. Use only „after-run
oil“ specially formulated for R/C engines. Do not use silicone shock oil or similar as they will
seriously harm your engine. We recommend to use our LRP After-Run oil (No. 37910), which you
should use regularly after using your engine.
Procedure:
First let the tank run completely empty at idle until it runs out of fuel (try re-starting it several
times), next put a few drops down the open carburetor and a few drops down the glow plug hole.
Spin it over for 5 seconds on the starter box and you are done.
Treat your engine with care and check it frequently. Due to the extremely high RPM this engine
produces, any fault can cause serious damage. All moving parts inside the engine are subject
to wear, you must know if a piston/liner/conrod has worn out and if they need to be replaced. If
you replace one part, please check if everything else is still in good shape at the same time. If
you only change one part and other parts are in bad shape, there’s the possibility that there will
be a new failure soon!
Some important matters:
• Cleantheoutsideoftheengineproperlybeforeyouopenit.Anydustordirtwhichgetsinto
the engine could make considerable damage.
• Checktheconrodfrequently.Ifyouwanttoreplacetheconrod,besurethebigendofyour
crankshaft is still round and at a good size. If not, also replace the crankshaft.
• Whenyoustartputtingyourenginebacktogether,makesurethateachpartistotallyclean
before installation and please use some oil (after-run is suited well) to lubricate everything.
• Becarefulthateachparthasitscorrectdirection,especiallypiston/liner/conrod.Pleasealso
check the explosion drawing. The lubrication hole in the conrod should be facing to the front
(direction to the carburetor).
• Beforeyouinstallthecombustionchamber,pleasedoublecheckthatyouinstalledallhead
shims.
• Useahexwrenchtoinstallthescrews.Whenyoustarttofeelresistance,stopturningthe
screw. Repeat this for each screw, use the star-technique to tighten all the screws complete-
ly. Do not overtighten them!
PROBLEM REASON SOLUTION
Engine does not start Glow plug defective - replace glow plug
Glow plug does not work
properly
- check the condition of the glow plug
- check the glow plug igniter
Engine is set too rich
(too much fuel, hits back)
- check carburetor settings, repeat tuning
procedure
- unscrew the glow plug completely and use
startbox for 5sec
Engine is too lean
(too little fuel, does not start)
- check carburetor setting, repeat tuning procedure
Engine doesn’t suck in the fuel - check the fuel line for possible damage
- check the carburetor setting
Engine stops after a
short time after glow
plug igniter has been
disconnected
Glow plug defective - replace glow plug
Bad fuel - replace fuel by fresh and correct type of fuel
Bad carburetor setting - check the carburetor setting, repeat tuning
procedure
Dirt in fuel line or carburetor - clean fuel line, clean & check carburetor
Fuel line damaged - replace fuel line
Loose glow plug or cooling head - tighten glow plug and/or cooling head
Air filter old or dirty - clean or replace air filter
Performance
decreases after
reaching operating
temperature or engine
stalls from time to time
Engine is set too lean - check the carburetor setting, repeat tuning
procedure
Glow plug defective or wrong
type
- replace the glow plug by a correct type
Engine runs too hot - run-in process is not completed
Shims under comb. chamber
wrong
- check number of shims
Engine still keeps
running at high RPM
for a moment when
you release the throttle
Bad carburetor setting - open mid-range needle ¼ turn at a time and
re-adjust idle-speed
- set idle speed lower
Glow plug, wrong type (too hot) - use glow plug with higher number (e.g. go from
5 to 6)
Shims under comb. chamber
wrong
- check number of shims