GTX DI Engine Problems

[kastevenson]

Hello all,
I'm new to the PWC world and a new owner to a 2001 GTX DI in great cosmetic shape for its age (see picture)

Brief backstory: I bought the ski from a family friend who had a good 15 years of service from the machine and had recently entered into the boat world and didn't need it any more. It has 175 hours and was serviced by a dealer at the end of every season. I got a real good deal on the ski and aluminum Triton trailer and had always wanted a PWC if a good enough deal came along. This seemed to be that deal. Bought the machine and spent 4 issue-free weekends this summer on the water - had a blast. Until....

Last Sunday a buddy and I had the ski out on the lake and had been on the water for about 20 minutes cruising around 40mph when all of a sudden we lost all power and the ski just died right in the water - no miss fires, noises, or coughing - went from running fine to nothing at all and wouldn't restart. After being towed back to land, I pulled the ski out and was able to get it to come to life for a few seconds if I stayed on the throttle. Then it wouldn't even do that much. Neither I nor the previous owner have had any issues out of it thus far. It has always started right up and ran like a top and has always been ran on the XP-S oil.

While trying to restart the machine on the water, I got a maintenance light twice (MANT, no beep codes).

I took the ski to the local dealer for a look-over and upon testing compression, both cylinders were pretty low (less than 90). His diagnosis was an engine rebuild based on that info alone.

Knowing that I've owned the ski for less than 2 months and am not heavily invested in it (less than $1000 for the ski and trailer), and knowing the complexity and age of the DI 2-strokes, I've got a few questions for you more experienced owners.

1) Should I have the rebuild done, along with the dealer going through the entire power-train to make it a mechanically "like new" machine (costing me much more than the ski is worth) and run it for (hopefully) years to come?
or
2) Cut my losses and sell it as is? (keeping the good times I've had, of course) The trailer has new tires and new electrical/lighting and should be worth 5 to 6 hundred by itself.
or
3) Is there anything else mechanically I should check and consider before settling on the costly engine rebuild.

Thank you for your time and input!

 

[68ragtop]

Not saying your dealer did anything wrong in the diagnoses, but I would put a compression gage on it yourself & make sure its in flood mode & check. the air & fuel injectors must be off when checking compression. this is done by holding the throttle to the bars before cranking the engine. Should be 140 or above.

IF both cylinders are legitimately down I would suspect it ran out of oil, has the wrong oil, might have overheated or it was running lean from a fuel system issue. Normally they will be a bit symptomatic when the fuel system is not spot on, so if it was running perfect I wouldn't think that's the issue.

 

[kastevenson]

Thanks for the tip,
I'll stop today and pick up a compression tester and report back. It seemed odd to me that it went from running great to nothing at all.

It has ran the XP-S oil its whole life until now; I had to order it and in the mean time I bought a different brand labeled as full synthetic for 2 stroke direct injection. http://www.wholesalemarine.com/quic...pwc-oil.html?gclid=CMiekNTtsc4CFQxahgodZl8FYg

 

[tkarvelis]

If the engine has 175 hours on it, you should rebuild the crank also. Once you hit 200, the bearings are shot, and you do not want a hole in the case. You should not mix oils. The oils when mixed can create a jelly type substance and not go through the oil nipples. Also, on a Seadoo, make sure it is API-TC rated oil. DO not use TCW3 oil. It should never be used on a Seadoo.

You did get a good price on the ski. Even if you part it, you should be ahead of the game.

 

[kastevenson]

I did a compression test this evening WOT, twice per cylinder. The front cylinder hit 60 both times and the rear hit 70 both times. Obviously that's way low but I'm still baffled how it went from running like a top to where we are now. Something in there gave up the fight real quick.

On a scale from "1 to Throw in the Towel", how difficult is it to pull out and rebuild one of these Rotax engines? I've got access to some knowledgeable 2-stroke guys, just lacking PWC/Rotax experience.
Like I said before, I'm not tied down to this machine and have definitely been shopping Craigslist and boat trader. I've been told the 2006 to 2010 non-supercharged 4 strokes are the way to go for a solid used ski...

 

[Coastiejoe]

Get a different gauge. Anytime we see numbers that low, always double check with a different gauge.

 

[68ragtop]

Makes me wonder if it was a lack of oil issue or possibly overheating. could have went lean on both sides, but It more than likely would not have been running all that well beforehand.

Does you gage hold pressure? Meaning you crank the engine over until the gage stops climbing, then when you stop cranking the needle holds? is there a check or Schroeder valve on the very tip of the gages threaded end?

 

[kastevenson]

I did 8 or so cranks per cylinder and the gauge climbed to the numbers above, held those values, and did not go down until I released the pressure valve on the gauge.

That's what's weird, I didn't get any beep codes or warning lights other than the inconsistent "MANT" light & alert when trying to restart on the water. I had been running the different oil for a while and had went through 3/4 gallon before this went down.

I'll pick up a loaner gauge from auto zone tomorrow to verify my measurements and report back. Thanks for the insight, guys.

 

[kastevenson]

Alright, I picked up a loaner compression test kit and got similar results: The rear cylinder hit a consistent 70 to 75 with both testers. However the front cylinder read 65, 80, 90, and a few mid 80's with both testers - pretty inconsistent.
Thoughts?

 

[Coastiejoe]

A bit inconsistent. But it doesn't matter. You have confirmed two sets of low readings. How many hours are on the crank?

 

[kastevenson]

The ski has 175 hours according to the display.

 

[Coastiejoe]

You can do a top end and be safe. If the crank had close to 300 then it is time for a full rebuild.

 

[68ragtop]

IMO the crank life depends on the care & wether the PO's ever fogged the engine. The bearings seem to fail more from rust than anything else. I think a low hour ski that sits stored most of the time is a time bomb especially if the engine is not fogged & the seat is left on tight with residual water in the hull besides. Incredible how much condensation moisture collects in the DI engines. If you run one for even an hour & leave it sit. Pull the spark plugs the next morning & there is usually a droplet of water hanging on the electrode. Everyone of mine did this. Guess where else all those water droplets collect?
No doubt all of our skis have this happen but DI's seem worse than others. Rusted & busted cranks are so common on them.


Still wonder why both cylinders are down. Almost have to pull the top to see, but I'm guessing it went lean from a fuel/pump issue. Overheated, or lack of the correct oil. Just my guess of coarse.....

 

[kastevenson]

The dealer did mention the condensation and seat removal issue and how most people don't know to do that... You'd think the orignal dealer would've mention that when the previous owner bought the machine new in 2001. I know the owner and she's pretty well "by the books" when it comes to stuff like that. However, I believe the ski was pulled up on a dry dock and covered up after use but was serviced by the same dealer after each season.

Correct me if I'm wrong but it looks like the following would be a good way to proceed (I've let my engine guy read your replies above):

Strip the top end down and check for major jugs/piston wear and see what kind of visual inspection can be done of the crank for rust. Obviously we wouldn't see bearings or most of the crank assembly but could get some idea if there's a major rust problem down there. Again, we don't have much experience in the PWC world.

What has your experience been in honing vs boring on a cylinder that's not in too terrible of shape. Also, do you have a particular company that is recommended for top end kits? In some quick searching I've found this and this.

I assume the Sea Doo shop manual would detail the breakdown procedure for the engine components (injection system, electrical, etc) and performing a top end job. Any direction for resources would be appreciated! Again, thanks for your expertise thus far!

 

[68ragtop]

Once you pull the head & cylinders, I think your going to find some piston & cylinder scoring or damage. Most of the time that won't clean up without going to an oversize bore. Once the head is off, you may be able to see if any debris has gone through by marks in the crowns of the pistons & combustion chamber. I guess if your going to tear it down, that would be the place to start. No harm in looking further.

 

[kastevenson]

Sorry to bring up an old thread but its been a busy fall and I haven't had any time to do anything with the ski.

In the mean time I have come up with a few more options I'd like some seasoned opinions on. Knowing I have less than $1000 in this thing(including trailer), right now my options are:
A) rebuild top end and inspect the crank for further damage hoping there isn't any rust or debris down there - ~$400.
B) have the dealer do the rebuild and inspect sub-systems and make it a like-new craft - $3k
C) Buy a rebuilt motor $1200 and do the swap myself. (Obviously would want to check/replace any ticking time-bomb parts while we are in there (starter, injectors, etc) This option would have a warranty and should be a solid engine for years to come.
D) sell it as is and find something else

Right now if I keep it, I'm leaning towards option C to ensure it's done right but also cutting the cost of the dealers labor. Does it seem foolish to put $1200+ in a 15 year old machine with old tech? Keep in mind the ski is in great shape cosmetically but I know there are other things to watch out for on these old skis. So, if I go this route, what else should be changed while we're waist-deep in this thing?

Honest opinions welcome

 

[AZ Sea Doo XP]

I would remove look at rebuilding the top end and bore the cylinders etc. I personally would not do a rebuilt engine. the $1200 is just the start. 175 hours isnt much. I got 400 on my last one, original crank. I would check the balance shaft oil when the top end is off and do that regularly as that is one of the most common causes of engine failures. I would also suggest checking the fuel pressure. that could explain why it just quit. compression doesnt to that and Di's are infamous for fuel pump failures. also make sure you are using a good/well charged battery. a slightly weak battery can make a big (doubt 60lbs big) difference. good luck!

 

[kastevenson]

Thanks for the tip AZ. Not saying I don't have a compression issue but I agree, the sudden stall seems like a fuel delivery issue. I read through the shop manual on fuel system testing. Looks like I need to get my hands on a gauge and necessary adapter hoses for the air system. Looks like the gauge and fuel hoses are pretty standard. Do you guys have a particular gauge set you recommend or will the standard loaner set at Autozone suffice (looks like it only goes to 100psi)?

 

[AZ Sea Doo XP]

when the fuel pump failed on a boat belonging to a friend of mine, it only produced about 75 lbs, so the 100 psi SHOULD work. if i remember correctly, the spec is 107+/-2 lbs. if it turns out you need one, there is an aftermarket company that sells them for about $150. that is what my friend did and it worked fine vs the SD pump for $700+! my suggestion is if you dont drink alcohol, you may want to start now!

 

[kastevenson]

Cool. I found an older thread talking about highflowfuel.com and their aftermarket pumps. I found a replacement pump on their site for an 01 GTX DI (HFP-342DI) for $80. Are there other recommended pumps out there?

Ha I'm beginning to see this true. I've always heard any kind of boat is a hole in the water that you pour money into.

 

[kastevenson]

Update: I think I've made my decision on what to do with this ski...

So yesterday before diving into troubleshooting the fuel pump, I tilted it back to drain the remaining bilge water out of the hull. We tilted it back and out ran a about quart of pure oil from the front of the hull. The oil tank was still quite full so our thoughts now is that there's an oil leak somewhere between the tank and the injectors which caused the engine to run lean for some time until it lost enough compression to kill over.

Being that I don't have a lot in this ski and I'm not looking for another "project" right now, I'm thinking about cutting my losses with it now and selling it as is to an eager 947 enthusiast to fix up and make right. If anyone knows someone like that send them my way.

Thank you guys so much for your help and input with this - its been a big learning experience to the world of Sea Doo. It seems I now find myself in the market for a clean, low hour, non-supercharged 4-tec. To Craigslist I go...

 

[68ragtop]

Assuming your ski has the two piece oil tank, (probably does) its probably leaking from the seam in the tank. I think more of them leak at least a little, than don't at all. Usually doesn't hurt anything except the environment & your wallet in extra oil.

No doubt lack of oil can take down the engine, but it would have to be coming from cracked injection lines to be the cause of the failure & the oil in the hull. I can understand your frustration though. If your oil level is above the oil tank parting line, My bet would be the tank is a likely culprit. pull the straps off the tank lift it up & see if there is oil sitting on the fuel tank just below.

 

[kastevenson]

Ah, I didn't know there was a seem in the tank. I probably over filled the tank...

 

[ski-d00]

I rebuild a lot of DIs still and would be interested in your ski. I also have a few 4tecs for sale but the only 155 I have is a 2007 RXP with 70 hours which is a 2 seater. I'd make you a great deal (around $3k) on it if you can live with a 2 seater but if you're doing family stuff you really should have a 3 seater.

 

[AZ Sea Doo XP]

this is a photo of the oil tank grommet that goes into the bottom of the oil tank. I have seen these leak OFTEN and it is common to find a pint of oil or more in the hull when they leak long enough. I would suggest investigating further before you decide to sell it!!