Carbs

How does the carb work marine four and two stroke?
A carb is situated on the engine, this is to allow fuel and air to be mixed for combustion.
Fuel lines feed the fuel bowl, the float controls how much fuel enters the bowl form there it enters a jet then it enters the venturi. The area of venturi becomes thin to allow fuel/air to mix the is passed on to the engine.

Identify the components in a carb?
Air horn, Choke plate, external valve vent, choke pull off, throttle body, mounting base, float bowl, vacume nipples, idle mixture screw, fuel inlet, fast idle cam,throttle leaver, internal bowl vent.

What are the holes in the emulsion tube for and how does it work? 
The emulsion tube sits in the main well and mixes the air and fuel from the air bleed and adjustment channel that finds it way to venturi.

How does the manual choke and automatic choke work?
A manual choke is cable that is pulled to open the choke. An automatic choke is an electric solenoid using a spring pulls the choke open. The purpose of this is when the engine is cold it allows more fuel in the venturi to warm the engine.What is the purpose of the float in the carb?

The float regulates the amount of fuel entering the cab to prevent flooding it dickates the needle movement.

What is the purpose and how does  mechanical lift pump work?
This transfers fuel from the fuel tank to the fuel bowl.

How does a vacuum fuel pump working on a two stroke engine? 
The piston creates pressure sucking fuel past the diafram into the fuel bowl.What pressures would you get from these types of pump?
3-5 psiWhat the difference between petrol and diesel fuel?
Petrol is more volatile and ignites at a lower temperature giving it a higher performance to price ratio.
Diesel is a cheaper simpler method of fuel but lacks in performance.
How does the fuel shut off solenoid work?
It is a safety precaution using and electric solenoid opening and closing fuel supply to the carb or injector pumpWhat is the four stroke cycle?
Intake,compression, power and exhaust.What does S.I mean?
Spark ignitionWhat does C.I mean?
compression ignition
When dismantling a carb what precaution should you take?
Detailing disassemble eg. remembering how to put it back together, very clean and organised work surface, keeping carb upwright making sure float doesn't malfunction.How does a bimetallic spring work in a automatic choke work?
Is in a sense like a thermostat where it expands and decreases causing the spring to open and close the choke in the choke housing.What is the purpose of the venturi and how does it work?
Works on atmospheric pressure and is like a aircraft wing design where the aerodynamics work in harmony to draw fuel and air at a balanced rate.Explain how a fuel cut off solenoid is checked and why is it fitted?
Multimeter check. or visual inspection.An engine lacks power. What is likely to cause this problem?
Lack of fuel, air leak, air blockage, malfunctioning springs and parts.How do you adjust the float in a carburetor?
Use a feeler gauge to adjust to the manufactures specificationsWhat is the purpose of a power valve?
Is a spring vacume loaded valve which opens under a high acceleration to allow more fuel into the engine to prevent pre detonation/ignition.What are some of the causes of high fuel consumption?
Running to rich, incorrect float adjustment, worn needle valve, defective choke.
How is the the idle and mixture screw adjusted?
With a screw driver, left is to open which is richer and right is closing and becomes leaner.When refitting a three multiple carburettor what should be done after installing them?
Synchronise carb adjustments together .
References
Car craft.com
Wiki.com
Google images
boatfan.com
Marinestrokefetish.com
boatsgonewild.com/dvd/1stedition.com

   TRAILERS

     There two main types of boat trailers.

• single axle: are for smaller boats and have the advantage of better maneuverability however they have a limited weight capacity.
• tandem axle: These are for larger heavier boats but have a disadvantage of having to maneuver in larger turning circles.
• 
  

single axle for smaller boats and tandem axle for larger and heavier boats

Boat length     gross vehicle weight rating( This is the maximum and vehicle axle can handle)

15'-17'            3500lbs

17'-19'          

3500lbs  

17'-19'            5200lbs

19'-21'            3500lbs

19'-21'          

 5200lbs

  

DESIGNS.


There are many boat trailer designs but the two main ones are bunk type and roller type.
Bunk type: 
Bunk types have marine carpet covered planks/skids. Are very stable but usually used smaller lighter crafts

Roller trailers:
Can be used for all types of crafts with and have the advantage of being able to adjust the rollers for the hull shape and the weight. The Disadvantage is the roller maintenance and replacement of rollers.

The trailer designs come in many shapes and forms depending of personal choice and the boat owners choice. A frames balance the center point of weight over the axle. The draw bar is to support the bow and has the winch attached to it.




Materials:
Boat trailers are usually made from Galvanised steel Aluminium.

DIMENSIONS restrictions:

The rules are as follow form New Zealand land transport:

It is not wider than 2.5 metres if they're loaded side by side.

Is not higher than 4.25 metres if they're loaded one above the other.

Is not longer than the standard length or rear overhang limits for that vehicle if they're loaded one behind the other.

If you have an over size load you will need special permission to transport it with pilot and safety vehicles.

SUSPENSION TYPES

Leaf springs fixed and floating

Coil springs with damper

Air bags

Wheels and tyres

Wheels are made from alloy or steel. Types have a recommended load capacity so you should always use the recommended tyre your trailer is going to carry.

A dolly wheel 

Hubs:

These are on the end of the axle and provides a place for the brakes bearings and tyres to be mounted to.

Stubs: These are a tapered steel rod welded to axle to house inner and outer bearings.

Breaks: Are only necessary after a certain weight is being towed and come in:

Disk breaks

Drum Breaks

Electric drum breaks.

Couplings:

These are and the front end of the trailer to lock the trailer on the towbar These can also houses break regulator system for the trailer. They come in two sizes 

50mm and 1/78 inches


Winches:
These to pull the boat onto the trailer to make life easier or if the boat is to heavy.

Lights:
Trailers have a power cord connected to the vehicle that makes the break lights or indicators come on when the car breaks.
Submersible lights are a must on marine trailers.

pics of some weird looking people