Compression test GTI SE 155 - water ingestion

[Milehighguy303]

Background: flying along at 60 mph on my well maintained 2007 Seadoo GTI SE 155 with 250 hours, enjoying a new jet pump, my exhaust temp warning light came on and I shut the engine off. I sprung a leak in my exhaust cooling system, and my ski very slowly started to sink as I waited for a kind boater to come along and tow me. My Good Samaritan boater couldn’t get me all the way to the dock due to shallow water, and by the time I could get to the dock, my ski was nearly sunk. I had actually tried to idle in and hang on the side of the ski - didn’t work. Wanting to try idling again, the engine water locked while turning over to start, but not running. Got home, pulled plugs, pumped water out of the cylinders, and started the ski. Idled perfectly at the 1700 RPM for 3-4 seconds, then seemed to water lock and stopped running In an instant. I pumped more water out of the cylinders (but not as much as I had previously) and started again. It ran very rough, seemed like on 2 cylinders, but I was able to accelerate a little bit, rev the throttle slightly. I shut it off, disappointed that I had bent a piston connecting rod when I started it the first time and it water locked up at idle. So I thought....

Before I start shopping for a new Seadoo, I thought I would check compression, to confirm my suspected bent connecting rod theory. To my surprise, I have an even 120 psi in each cylinder. The likelihood of bending all 3 rods evenly is unlikely, and so I think my engine is actually ok. I still need to figure out where my exhaust cooling leak is at, why the ski stopped idling so abruptly, and why the ski is running so poorly now. But I have renewed confidence in the engine.

So the question is, what is good compression on a 155 engine? Is my renewed confidence that I don’t have Internal engine damage justified? I saw some post of 135 psi on a ski with 85 hours on it, another post of 185 psi (which sounds incorrect and impossible to me). Is my even 120 psi for all 3 cylinders reasonable? This was essentially a dry test too (for those wondering). Any opinions on my compression results? This ski always started easily and ran strong, until this recent ingestion event.

Hope to see you back on the water...

 

[skiasylum]

I will start off by saying that compression values for a 4tech can be all over the place from 110 to 185 and the ski can still run great. Seadoo does not mention a compression test anywhere in their service manuals and only refer to a leak down test for troubleshooting and to help determine the health of a engine. As soon as you tried to start your engine with water ingestion was a big red flag for probable engine damage.
There is a section in your service manual on how to service a water flooded engine. Owner manual states it needs to immediately be taken to a dealer for service.
Damage is already done and I suggest you get yourself a service manual and read the info on how to service a water flooded engine, you can then make a more knowledgeable decision on how now to proceed.

 

[Milehighguy303]

Thank you, I appreciate the response. I am using a vacuum to try and suck out all the water I can from the cylinders, wish I would have done that first, and following manual recommendations. Hope to save this ski... we will see.

 

[ski-d00]

You have to pull your intake manifold to drain it. It will continue to supply water to your cylinders since it holds about a gallon that will be gradually sucked in.

 

[gazzaskirepair]

120 is on the low side but should still run ok
Check the plastic muffler / resonator on the right side of engine compartment
They made of plastic so overheating damaged them at the inlet clamp area

this overheating is normally caused by the three cooling orifices in the exhaust J pipe or new exhaust pipe that mounts on the exhaust manifold
You’ll need to flush the oil system too and check electrical connections for water ingress
Remove connectors and blow them out with low pressure compressed air

 

[Milehighguy303]

If you are curious... I used a shop vac for about 2 hours where my throttle body connects to the rubber boot, sucking air through the air box as if the engine was running, thinking The air flow would help dry out any remaining water. Didn’t see any water, and confident it is dry. Then pulled all my plugs again, still getting some water in my cylinders from the intake, and sucked each cylinder dry a couple times while turning over the engine for about 30 seconds each cylinder. It idles great, no more water. Changed the oil and filter and idled around the river for 2 hours with the oil cap off holding paper towels near the oil filler opening and boiled any remaining water residue out of the engine. I had some oil and water steam escape. I didn’t want to accelerate much with questionable oil quality, but noticed I do have a stumble/hesitation above 3500 RPM as I took off on little tests. Back home in the garage, I Changed the oil and filter again, so I have good clean oil now and splurged on new OE coils at $120 a pop. Replaced plugs too. I can tell on the trailer I still have a stumble/hesitation at RPM 3500+ and rechecked compression - still an even 125 psi in each cylinder. That was wasted coil money. I am now thinking a fuel injector is maybe rusted or corroded a bit, but at $178 a piece, I don’t want to drop $550 on injectors as a guess. I am going to order some aftermarket injectors at $55 each and see if that gives me full and smooth power again. If successful, maybe I will eventually replace them over time with OE injectors for added peace of mind quality.

Oh, and the cause of all this trouble? A rusted hose clamp broke on my exhaust cooling hose where it connects at the rear of the ski to the jet pump. Blew the hose right off the nipple, and I was getting no cooling water to my exhaust, turning on my exhaust temp light and allowing water into the hull, sinking me. Fixed that for $1.15 with a new clamp. Same thing happened to my buddy a couple years ago, but he was able to get back to shore without sinking. If you have an older ski, it is worth $1 to replace that clamp. I wish I would have done it when my buddy told me about his experience, but I wasn’t totally sure what clamp and hose he was talking about, and the clamps I could see on my ski are all shiny and clean. You can’t see this clamp easily and it rusted underneath the worm gear area, touching the hose.

stay tuned...

 

[skiasylum]

Make sure you use marine grade 404 stainless clamps, cheap stainless clamps will rust.

 

[skiasylum]

You really need to pull your intake manifold and exhaust system and drain the water out. They both hold a lot of water and the water in the exhaust will make its way into the motor and oil when you run it.

 

[ski-d00]

If you are curious... I used a shop vac for about 2 hours where my throttle body connects to the rubber boot, sucking air through the air box as if the engine was running,

The water isn't in your airbox which has a drain hole at the lowest point. It is in the intake manifold which typically doesn't draw water into the cylinders until you get to higher rpms, sounds familiar?. Takes 20 minutes to remove the intake manifold, only 7 bolts and some electrical connectors.

Make sure you use marine grade 404 stainless clamps, cheap stainless clamps will rust.

Actually, you want a 300 series, like 316 which is what Tridon(OEM supplier for BRP) uses in marine since it has a higher corrosion resistance. 400 series, like 430 used in clamps, has higher carbon content which makes it stronger but will rust quicker.

 

[Milehighguy303]

I got good news. I got my $55 injectors online today and installed them. Smooth power, no stumble on the trailer. I think I have found the issue - but I don’t love these injectors, because it seems harder (longer crank) to start than with OE injectors. Turns over longer, but there is an obvious improvement to how it runs. And Water test tomorrow!

 

[Milehighguy303]

Haven’t made it to the water yet, but the shop manual troubleshooting section says a hard to start condition, turns over fine, could be air lock in the fuel rail and to see the Engine Management section. There is nothing mentioned in engine management or fuel system section about air lock. And the manual doesn’t specify a fuel rail purge or bleed process when changing injectors.

Does anyone know about air lock after changing injectors? This ski runs great now on the trailer, but for peace of mind, I want it to start like it used to, immediately upon pressing the start button. Cranks for maybe 4-5 seconds and starts with a stumble, then idles and runs fine. Subsequent starts within a few minutes of the initial start seem to start better, if not immediately.

 

[Milehighguy303]

Well, my ski is back to 100% and runs as good as before. Hit 60MPH. I think I saved it and the $55 injectors took the stumble out and restored full power.

The only thing is that it has a 5 second crank to start, and often after 5 seconds, the bendix will disengage from the flywheel and the starter keeps spinning until I release the start button. Then I try to start again, and it stumbles and starts. Once running, it is great. And restarts immediately, how I always expect, if only sitting a few minutes.

I don’t have an explanation for the starter... it is a new OE starter 1 year ago (but got drowned to some extent in salt water) and I have a charged OE battery that was new in October and has 4 or 5 hours of use on it. I am quite sure the delay start is new with the aftermarket injectors. i had a stumble at about 3500 RPM and higher, but ski started quickly With the OE injectors. I am very tempted to put OE injectors in it, even at $178 a piece.

Any thoughts from anyone?

 

[Milehighguy303]

Ok - if I give it a little gas as I start it, it fires right up, immediately. I shouldn’t have to give it gas... but it makes me think my $55 aftermarket injectors are maybe not delivering fuel as needed at start. The old OE injectors started right up, but were salt water damaged and didn’t work well above 3500 RPM. I can save up and buy OE injectors someday.

But bottom line, I saved my sunk Seadoo. I am pretty happy. See you out on the water!

 

[Mekanix]

So did you actually remove the intake manifold and drain the water out of it?

 

[Milehighguy303]

Nope. Just disconnected the intake tube at the throttle body (which I later learned wouldn’t likely pull any water thru the air box) but it was a precaution. Then pulled all my plugs, and cranked the engine over at Wide open throttle to disable the fuel injectors, while sucking with the shop vac in each spark plug hole. ran it about 3 hours since on one trip and runs great. I am very fortunate. Starts ok, but better with giving it slight gas When starting. Never had to do that before the sink, but not a problem.

 

[WaTeRMaNiaC407]

Ok - if I give it a little gas as I start it, it fires right up, immediately. I shouldn’t have to give it gas... but it makes me think my $55 aftermarket injectors are maybe not delivering fuel as needed at start. The old OE injectors started right up, but were salt water damaged and didn’t work well above 3500 RPM. I can save up and buy OE injectors someday.

But bottom line, I saved my sunk Seadoo. I am pretty happy. See you out on the water!

I had this exact same problem with my Speedster 150 after a motor rebuild. Starter would disengage after a couple seconds of cranking and everything else you are experiencing. I never really was able to track the problem down but I did make it better after changing the ground cable to the motor.

 

[Milehighguy303]

I am confident my starter disengaging was a poorly charged battery. I bought a new charger, got a good charge, and no more starter issue.