Rebuild motor GP1200, assemble motor

This rebuild job use all Genuine parts.

Pistons, rings, pins, smallend brgs and gaskets.

After boring job. Scavenging side

Exhaust side

   Measurement of pistons.

#1  84.505mm  #2 84.502  #3 84.502

 Measurement  of cylinders bore.
#1 85.615mm  #2 85.613mm #3 85.614
Piston clearance are #1 0.110mm  #2 0.111mm   #3 0.112mm     all good
 

After fitted pistons.

After fitted cylinder.

After fitted cylinder head and carbys motor put back in engine room.

Fitted exhaust sys.

Now try to engine start.

Rebuild motor GP1200, carbys service

Carby assy

Dismantled carbys

Fuel pump diaphragm were stretched.

One way valve of fuel pump were squashed. This may cause to pumping problem of fuel as make fuel lean.

LH original, RH improve parts as avoid to squash pump valve.

Rebuild with new kit, new valve & seat and new pump valve assy.

We must do crabys service when rebuild motor. If carby has problem like a this case engine will not run well or damage engine again after rebuild motor.

Rebuild motor GP1200, extra inspection

Engine mounts

All condition are good

Make sure engine bottom bolts tension with torque-wrench.

Drain oil and check inside and cleaning.

Check and clean oil filter. Check work of oil level sensor.

Fuel tank, drain all fuel

Found water about 200cc from bottom of tank

Inspect fuel sender

Res fuel line pipe hit or very close the bottom cover and this may cause of choke fuel flow and make a fuel lean.

It's like a this from another angle

Cut bottom of pipe.

Fuel cap

Seal rubber been damaged. Needs new seal.

This may cause water get into fuel tank.

Pressure test of fuel tank with sender, fuel tap, fuel hoses. All good.

Rebuild motor GP1200, measure warpage

Another important inspection of when rebuild motor.

Measure warpage of flat face of engine parts.

Use straightedge and thickness gauge.

Cylinder is check cylinder top, bottom and exhaust side. This cylinder is all good.

Crank case top is good.

Cylinder head is out of specification. Needs resurfacing.

We check all parts when rebuild job for avoid pressure leak problem.

Rebuild job is not just dismantle parts and assembling parts, must needs check and inspect parts.

Just local cruising from water and road

7:30am started cruising

Heading to Surfers Paradise

Surfers Paradise

4pm at Burleigh Heads, back of view is Surfers Paradise

Q1 tower  323m

View of Surfers Paradise

Rebuild motor GP1200, check crank shaft condition

This time just top rebuild but better to check crank shaft conditon.

Inspect crank shaft degree of twist.

This crank shaft is pass of inspection. This is very important when rebuild motor.

Rebuild motor GP1200

This ski is 1998model Yamaha GP1200. This GP1200 is still popular here in Australia because good for surf ride as right weight, powerful motor and small hull.

I heard piston slap noise when service this ski and now due to replace pistons.

This GP1200 needs replace piston every 100hr.

This customer requested me a rebuild so I dismantled motor.

Removed Exhaust pipe and Cylinder head

Ex side of cylinder

In take side of cylinder

In take side piston

Ex side piston

Amazing! all pistons are damaged as engine was still run and all cylinder had good compression because piston rings are not damaged. If this customer keep use more with this conditon may occur to more damaged such as piston will be broken pieces and then broken crank shaft  and crank case. It is so lucky to find problem before big damage.

Flushing connector,,,,,

When I serviced YAMAHA FX-HO,
I found bilge hose came off from strainer and that was damaged by coupling.
Bilge strainer is locate under the coupling.

I found damaged piece of hose and tube on the bottom of engine room.

 I removed coupling cover for replace damaged hose then I heard sound something fallen.

It was flushing connector, I found just under the coupling.

Other side was damaged like a cut half.

So customer dropped this connector before and when he ride may be after jump or something this connector stuck between coupling and coupling cover like a above picture. Also then this connector hit and pick of bilge hose.

Carbys disaster

Hi every one,
I show some picture of carbys from GP1200R today.
This ski was sitting for long time more than 6 month and now engine won't start.
Inside of carbys are damaged by corrosion very much.
Must be water sitting inside of fuel tank.