launch at Valle de Bravo, Mexico powered paraglider launch at Gardiner Turf Grass farms

SOUTHWEST AIRSPORTS

paragliding training center

New paramotor assembly guide

by Had Robinson

Purchased a paramotor?  Pilots need to be careful that it is ready to operate.  Failure to follow the proper steps can ruin an engine.  This checklist is primarily for the Miniplane Top 80 but the information is general and can be applied to other paramotors.  If you have any questions about how to prepare and run your new engine, check with your dealer.

WARNING: MOST PARAMOTORS ARE TWO-STROKE ENGINES AND MUST HAVE OIL MIXED WITH THE FUEL!  YOU WILL QUICKLY DESTROY YOUR ENGINE IF YOU DO NOT MIX THE CORRECT AMOUNT OF OIL WITH THE GASOLINE!

A. Fuel equipment

Mixing bottle  The best is from Shoreline Marine and is sold by Sports Academy and others.  It is simple, well marked, and can be sealed to keep dirt out.  Do not use an open mixing container.  It will collect dirt quickly and clog your fuel filters.  Clogged fuel filters are one of the easier ways to lean out your engine and burn it up.  Clean fuel is essential to the best engine performance and longevity.

Seasense Oil Mixing bottle 

Siphon  A fuel siphon is the only easy and safe way of getting fuel into and out of a paramotors.  Here is the best one and a comparable that is available at Academy Sports.  The secret of these siphons is that they do not require sucking on the hose.  The siphon is started by jiggling the end up and down, which starts the siphon.  The dinky siphons at Walmart would take 20 minutes to fill your tank.  SafetySiphon The Chinese knock-offs available at Harbor Freight do not have the right kind of hose and will kink and collapse once the siphon is started.  Furthermore, the jiggle valve at the end is inferior.  The better quality siphons have a much better jiggle valve and a hose which will last years.  However, if you must use ethanol fuels, any hose will only last a couple of years before it stiffens up.  Replacement vinyl tubing for the siphons can be purchased from any hardware store.  It also a good idea to store the siphon in a cloth bag as it keeps dirt out of your fuel.  The filters in paramotors (if they are any good) clog easily.

Tanks  It is important to have (2) gasoline tanks.  One should be (5) gal and the other (2) gal.  This is because you should not store gasoline mixed with oil more than a week or two.  The additives in gasoline, especially ethanol (if present), attack the lubricating properties of the oil.  Stored separately, AVGAS, for example, will keep for years and fully synthetic oil will probably keep for a year or so.  Stale fuel and stale gasoline are both great contributors to overheating and bearing failure in (2) stroke engines.  Our shop table is lined up with burned up engine parts caused by pilot carelessness with regards to fuel age and quality.

Note: Metal containers are the best for storing gasoline because, unlike plastic, UV from sunlight cannot penetrate metal.  UV causes any kind of gasoline to deteriorate.  If you do use plastic jugs, especially clear ones, store them in a cool, dark place.

Labels  I label all of my tanks with a removable tag.  I use white tags with a wire on it to put on my (5) tanks to indicate what kind of fuel it is and when it was purchased.  I have thin plywood tags with strings that I put on the (2) gal tanks to indicate the fuel/oil mix ratio.  Questions like, "Is my gasoline too old to use?" and "I can't remember whether this is 1.5%, 2.0%, or 2.5%?"

Fuel/oil specifications  Here are the mix ratios and fuel/oil specifications for various paramotors.

B. CHT

All pilots should install a CHT (cylinder head temperature gauge) and a tachometer/hour-meter on their engines.  The Top 80 with the ABM frame requires the TTO sensor extension #V300-24.  Miniplane-USA has these items.  A CHT will alert pilots to pending problems with their engines, especially the number #1 killer of all paramotors: overheating.  The number #2 killer is failure to mix 2-cycle oil with the fuel, use the correct ratio, or use the correct type of oil.  A CHT will not let you know if the fuel has no oil mixed with it.  Increasing the oil to fuel ratio does nothing to help extend engine life and may, in fact, ruin it as noted by engine manufacturers.  Avoid ethanol fuels at all costs.

C. Threadlock

Manufacturers often do not apply threadlock to critical fasteners. The following generally applies to various Miniplane engines.  Make sure that the following have BLUE threadlock applied:

D. RTV sealant

When assembling a new paramotor, there is only one place where it should be used and this is the exhaust flange gasket (Note: not all motors have this gasket).  The best RTV to use in this hot area is the "Permatex Ultra Grey".  It is available at all auto parts stores.  Go to this page for more detail on the copper gasket for the Top 80, others are similar.  Do NOT apply sealant on the exhaust manifold side of the Top 80 copper gasket but only on the cylinder head side.  Non-copper gaskets which seal non-spring loaded parts should have sealant on BOTH sides of the gasket e.g. Polini Thor models.  DO NOT APPLY SEALANT OF ANY KIND BETWEEN OR ON SPRING-LOADED SURFACES OF THE EXHAUST SYSTEM.  For some important tips on using RTV, see the Top 80 Specifications page.

E. Assembly

1. Assemble the paramotor according to any instructions received.  If there are not any, this assembly video for a Miniplane Polini will help.  Be sure to install the propeller in the correct position.  I recommend doing a compression check on your new engine and record it in a log.  That way, you can periodically evaluate the actual condition of the important mechanical parts of your engine.

2. If there is a redrive on the motor, be certain that it is filled with the correct type and quantity of oil.  If this is not done, the seals, gears, and bearings on the redrive will be quickly ruined.  Be sure to change the oil after the first (10) hours of use and every year thereafter.  Engines with wet-clutches should have the oil changed every 25 hours or less because of the clutch particles that quickly contaminate the lubricating oil.  Oil is cheap compared to the cost of fixing a damaged redrive.

3. There are (2) areas where serious wear occurs during operation.  Unfortunately, Miniplane does not provide any protection to these surfaces.

a. Be sure to wrap black electrical tape around the throttle cable wherever it contacts the engine frame.  A piece of split hose can also be used.  If you do not do this, the cable will gradually wear away and a.) jam/break the inner throttle cable and/or b.) short the kill switch wire.
b. If you have the Miniplane ABM frame, the side bars will constantly rub and grind away at the (2) upper side sticks where they screw into the frame.  Pilots can wrap the side sticks at the joint with electrical tape or, better, use a piece of automotive heater hose to protect the surfaces.

4. The side sticks will loosen and may come out of their sockets after a dozen or so hours.  Take a piece of electrical tape and wrap it around the joint.  DO NOT USE THREADLOCK ON THE SIDE STICKS!

5. Prime the carburetor  If this technique is used, the engine will start the first time, every time.  If the carburetor does not have a priming lever, use the end of cotton swab that has had the cotton removed.  Sticking a metal object into the metering lever diaphragm could injure it.  A properly primed engine will rarely need choke except when pilots start their engines while flying and cannot prime them.

6. Avoid running the engine on the ground unless it is grass or clean concrete.  The WORST environment is a beach.  SAND RUINS PARAMOTORS!  Sand gets sucked into the engine and chews up propellers.  Smart pilots will launch from grassy or concrete areas.  If you have to launch from the beach, use only enough throttle to get airborne.

7. After the engine starts, let it idle for a few minutes.  The carburetor must be adjusted for your particular altitude and environment (humid or dry).

8. New engines should be broken-in properly and then only flown for short periods, avoiding full throttle until a full tank of fuel has been consumed.

9. Test fly the engine.  If there are any problems, read this section on performance issues.

It is unlikely that there are ignition or mechanical problems.  The fuel system test is simple.  If the pilot does not want to fix the problem, the results of the test will help the dealer or repair shop.  If the fuel system does not pass the quick test, contact the dealer.  The engine should be returned for a professional evaluation.

Rarely, Miniplane will have an engine that was assembled incorrectly, even damaged and/or missing sealant in critical places.  A professional can find the problem and fix it quickly.

10.  If the engine will be stored for more than a few weeks, purge the fuel system or drain the fuel tank and run the engine until it stops.  If this is not done, the engine may not start again until the carburetor is rebuilt.  In any case, carburetors should be rebuilt yearly.  Ethanol fuels attack and destroy fuel system parts.

vulture