Remove and reinstall GP1800 transom plate

[K447]

There is a gap in the sealant between the transom plate and the intake grate. I am assuming there is also sealant missing where the transom plate meets the hull.

Jet pump ventilation and plenty of rev limiter action during hard acceleration from low speed.

I can see daylight in at least two places from inside the pump where the transom plate meets the intake grate.

I also have a 'mystery leak' somewhere in there that allows a few capfuls of water to accumulate inside the hull after each ride. I suspect leakage around the water hose fittings that pass through the transom plate.



What do I need to know before I try extracting the transom plate from the hull?



Best method for pulling the transom plate away from the sealant?

Any potential issues (or tips) regarding engine to jet pump alignment during transom plate reinstallation and jet pump reassembly?

The service manual instructions seem straightforward.

[K447]

there's an old saying: if it aint broke, don't fix it

Ah, but it is broke. There is a gap in the sealant that allows air to get sucked into the jet pump under acceleration.

Much reduced thrust = must fix.

It would be nice to resolve the mystery leak too.

[txgp1300r]

Ah, but it is broke. There is a gap in the sealant that allows air to get sucked into the jet pump under acceleration.

Much reduced thrust = must fix.

It would be nice to resolve the mystery leak too.

Yes Sir !

Totally agree what kind of sealant ?
Loctite 5900, 3M 4200, or Great Stuff?

[K447]

The visible air gap in the sealant was in the lower half, where the intake grate meets the transom plate, so I removed the intake grate.

The intake grate is a Worx WR246

I originally installed it using the Yamaha stock rubber seal that fits between the ride plate and the intake grate. This 'worked' but required trimming the two outermost rubber blocks from the factory piece. This seemed like a hack solution, and I felt the modified rubber piece never really fit well.



I now have the Worx WR0710 stuffer kit for this intake grate, which fills in the large void spaces in the casting.



Question: What is the recommended method for sealing the gap between the 'fully stuffed' intake grate, the transom plate, and ride plate?



Hacking all the rubber blocks off the factory rubber strip seems unlikely to create a satisfactory result.

[K447]

Why are you messing with it?

Is it not under warranty?

Aftermarket intake grate is where the seal gap was. So not a warranty thing.

[BLASTER 1]

It's a lot easier to reseal your transom with the rideplate off. When I did mine after taking the 4 nuts off mine would have literally fell on the floor if the studs hadn't stopped it.

After you get it off you'll want to fill the voids with epoxy or amazing casting resin it will give you a much bigger area for the sealant to do its job.

By the way all of the yami sealant stayed on the hull the transom was clean. Scrape off all sealant clean with acetone then rough up with sandpaper clean again.

I used 5200 and it's leak free

[TimeBandit]

Why are you messing with it? Is it not under warranty?

I don't think there is a single fully sealed pump rolling off any assembly line, as it is highly likely that Yamaha will not consider air-leaks into the pump's intake system a defect. That's why after-market products exist - as they help fill the gap (excuse the pun) of where OEM's fall short often times.

[BLASTER 1]

Also if you plan on running a dedicated line to the cooler it's easier to do it now and if your using a candoo you can remove the whole hamster wheel assembly and block off the hole in the hull with 2 pieces of round aluminum plate. I did and it come out awesome.

[jetdawg701]

Can also fill the intake grate with an epoxy filler and retain the factory rubber strip, then seal it up with silicone, it really helped with cavitation. Transom leaking small amounts of water into the hull is a separate issue and it will need to be resealed eventually. Anyone have pics of the pump transom plate surface area that mounts to the transom?

[K447]

It's a lot easier to reseal your transom with the rideplate off.

When I did mine after taking the 4 nuts off mine would have literally fell on the floor if the studs hadn't stopped it.

After you get it off you'll want to fill the voids with epoxy or amazing casting resin it will give you a much bigger area for the sealant to do its job...

After my photos were taken the ride plate and intake grate were removed. At the moment the only thing still attached to the hull is the transom plate.

The Worx intake grate cavity filler pieces are set into place with 4200 Fast Cure, should be quite solid by morning.

Before the transom plate can be removed, the steering cable mount has to come off?

[K447]

Also if you plan on running a dedicated line to the cooler it's easier to do it now and if you are using a candoo you can remove the whole hamster wheel assembly and block off the hole in the hull with 2 pieces of round aluminum plate. I did and it come out awesome.

I do have the CANDooPro GPS speedometer module, and the factory paddle wheel sensor has been removed and a filler plate installed.

The speedo cable grommet through hull fitting is being used for the sonar sensor for my Garmin chart plotter.

[Quinton Robbins]

I'm happy to see this thread. I've been wanting to pull my transom plate as well.

[BLASTER 1]

After my photos were taken the ride plate and intake grate were removed. At the moment the only thing still attached to the hull is the transom plate.

The Worx intake grate cavity filler pieces are set into place with 4200 Fast Cure, should be quite solid by morning.

Before the transom plate can be removed, the steering cable mount has to come off?

No, you can leave cable alone

[Kaybat]

I use the pump seal kit for my OEM grate, then cut the blocks off the rubber seal( I think that's what r&d says to do with their kits)

[Gus13letter]

Sorry I am late to the party, but I found that when I installed a WORX grate on a friend's ski, I also saw daylight between the intake grate and transom plate. The WORX fitment sucks and cavitated so bad. I filled the intake grate in with fiberglass resin, and did so to allow the use of the stock rubber piece that goes inside the grate and between the plate and sealed it when installing it. I also have done this with the stock intake grate and has worked well.

The Riva grate fits so much between and their pump seal kit is also very nice. Unfortunately the Riva grate does cavitate 1 - 2 blips more than stock on holeshot but works awesome in choppy water.

When installing transom plates I always use 5200 and make sure it is aligned to the alignment tabs. You can pull the transom if needed if you use 5200. You just have to heat the transom plate up to loosen the 5200 adhesive. Also make sure you re-torque the nuts holding the transom plate in, every 15 minutes. I do this 4 times.

Once the hoses are off and the 4 nuts are removed from the transom plate, it will almost fall out. The factory sealant sucks. The steering cable does not have to come out to pull the transom plate.