Buying 1st PWC...need mecahincal advice first!

[OutlawBiz]

I am in the process of purchasing a 1998 SeaDoo GTX Ltd. I know NOTHING about PWC's (will be my first one). I basically want something to pull my small kids around on tube etc. so opted for the 3 seater with 787 RFI motor (I think that's the size).

Owner has told me that motor has been rebuilt (not sure to what extent). He was going to check the compression for me today and let me know what it is. What is an "acceptable" compression for this motor. He said it has 245hrs on it but is in great shape. Current owner is a car mechanic by trade, so has "mechanical" knowledge.

I know 245 hrs sounds like a lot...but I did the math and it only averaged out to about 19hrs a yr. And here in SD we can only use about 4-5 months a year...so about 5hrs a month which sure doesn't seem like a lot.

Any other questions / concerns I should address before purchasing!?

Thanks in advance...I am having a blast browing these forums!

 

[ski-d00]

most importantly, you should ride for at least 20 minutes since you are not familiar with PWCs. check engine compartment while in the water to make sure it's not taking on water and not leaking water from the motor. it should accelerate without hesitation and idle very smoothly and reach a top speed of around 55-60mph on the speedo. you should watch him check the compression, not take his word for it. it should be 150psi range and both cyl equal. ask who did the rebuild and what all was done, whole engine including crank or just top end rebuild. 245 hours is about normal but typically needs a rebuild around 200-250 hours. ask what oil they use, should be using full synthetic Bombardier XPS oil, if they are using outboard motor oil, don't buy it, it will blow up. check underside of hull to look for gouges or cracks, look at the impeller through the intake grate while you're there, should not have bent edges.

 

[Dr Honda]

Yep... what he said.

 

[OutlawBiz]

OK...talked to seller. The compression test showed both cylinders at about 115. When I asked about the rebuild, he said it was done when he bought last year and didn't know any details!? As far as oil...he didn't know exactly...he figured "marine oil"!?

Thoughts?

 

[OutlawBiz]

So...115 compression on both cylinders...is that acceptable for a '98 with 245hrs with a rebuild!?

IF "marine" oil was used...can I simply do an oil change once I get it and use the full synthetic Bombardier XPS oil or is there more too it than that?

What is this "gray hose" issue I keep reading about!? I assume it was a situation where as there was a bad product used from the factory. How difficult is it for me to determine whether I have these "gray hoses" on my ski afer purchasing? If they are in use, is it an easy fix for a pwc novice of does a dealer / service dept nedd to get involved?

 

[Dr Honda]

Offer the guy $500 if it's in good cosmetic condition, because that engine is done. Most seadoo engines will be showing 150 psi on a rebuild, and 135 psi is what I normally call the bottom of the usable pressure. Anything lower than that... you will have running issues. at 115 psi... it may start on the trailer, but once it's in the water, with a load on the impeller... it won't go anywhere.

If the guy bought it "last year with a new rebuild, and doesn't have any details".... then it wasn't rebuilt, and he's selling it because it doesn't run right. Also... if they cont tell you want oil he was using... then assume he was using the wrong oil. (the oil tank needs drained, cleaned, and survived)


OK... the "Gray" hoses... also known as Tempo fuel hose.

No... this was not a bad product from the factory. Actually, its a very good product, and it is USCG approved fuel hose. The problem is, that hose is not approved for fuel is alcohol in it. Automotive fuels have had alcohol for the past ten years, and that will attack the interior of the Tempo hoses. This causes it to break down, and send green goo into the carbs. General rule is to change it anytime you see it. (We use regular automotive hose)


With all that said... either get it very cheap, or go look for a different ski.

 

[SabrToothSqrl]

The 1998 GTX LTD has the 951 non RFI engine.

 

[OutlawBiz]

Offer the guy $500 if it's in good cosmetic condition, because that engine is done. Most seadoo engines will be showing 150 psi on a rebuild, and 135 psi is what I normally call the bottom of the usable pressure. Anything lower than that... you will have running issues. at 115 psi... it may start on the trailer, but once it's in the water, with a load on the impeller... it won't go anywhere.

If the guy bought it "last year with a new rebuild, and doesn't have any details".... then it wasn't rebuilt, and he's selling it because it doesn't run right. Also... if they cont tell you want oil he was using... then assume he was using the wrong oil. (the oil tank needs drained, cleaned, and survived)


OK... the "Gray" hoses... also known as Tempo fuel hose.

No... this was not a bad product from the factory. Actually, its a very good product, and it is USCG approved fuel hose. The problem is, that hose is not approved for fuel is alcohol in it. Automotive fuels have had alcohol for the past ten years, and that will attack the interior of the Tempo hoses. This causes it to break down, and send green goo into the carbs. General rule is to change it anytime you see it. (We use regular automotive hose)


With all that said... either get it very cheap, or go look for a different ski.

Thanks for the info / advice Dr. Honda! I realize you are in Pittsburgh...but do you have an idea what a top-end rebuild could / should cost if need be done in SD!? I will call a local SeaDoo dealer and ask too...just thought you might have a ballpark cost. Thanks.

 

[ski-d00]

With 250 hrs and an unknown history, you will need a bottom end rebuild as well, imo. If the wrong oil was used, it will ruin a crank bearing and it is just a matter of time before it goes and will then do major damage. Complete rebuilds should cost $1500 to $2500 at a good shop, top end rebuilds $600 to $1200.

You need to be smart, you can easily end up spending more than the ski is worth, check value at NADA.com. If you can do your own work, you can save a ton of money, only about $600 for a complete rebuild or $300 for a top end but requires some knowledge.

You said the ski was a GTX LTD but I think you meant a GTX RFI, correct? The RFI is gold, maroon, and white with 787 RFI while the LTD is only maroon and white with 951 carb.

 

[OutlawBiz]

You said the ski was a GTX LTD but I think you meant a GTX RFI, correct? The RFI is gold, maroon, and white with 787 RFI while the LTD is only maroon and white with 951 carb.

I haven't personally seen the ski yet...family acquaintance is selling and I have only seen pics and emails / texts thus far.

Seller said it is a 1998 SeaDoo GTX Ltd. It is maroon/white. I swore he said it was fuel injected!? Here is waht it looks like (not exact one but same color / model etc.)

So...you think it is carbed our injected!? Man...this is confusing!

 

[ski-d00]

That's the GTX Limited, has 951 motor with dual carbs, not fuel injected. I personally think this is a better ski than the 787 RFI, definitely faster.

 

[OutlawBiz]

That's the GTX Limited, has 951 motor with dual carbs, not fuel injected. I personally think this is a better ski than the 787 RFI, definitely faster.

Thanks ski-d00...so, is this a 2-stroke or 4-stroke unit?

I was told by a local seadoo mechanic that 115 compression on a 13yr old 2-stroke is fine/acceptable. If it is a 4-stroke...might be a little light.

I am awaiting a return phoen call from the seller with these same questions, thought if I knew before talking to him I might sound a bit more "intelligent" when visiting with him about the ski! =D

 

[ski-d00]

it is a 2 stroke and 115 compression is not acceptable, the local seadoo mechanic was wrong, it's not fine/acceptable, it's low. it will run and may idle a little rough but it won't have the power it should, will also foul plugs quickly and would expect it to get worse fairly quickly. now is the time for a rebuild and I'd suggest a complete rebuild with those hours.

 

[Dr Honda]

Thanks ski-d00...so, is this a 2-stroke or 4-stroke unit?

I was told by a local seadoo mechanic that 115 compression on a 13yr old 2-stroke is fine/acceptable. If it is a 4-stroke...might be a little light.

Oh MY F'ing G*D !!!!!!

a real seadoo mechanic said that !!!

Go back and slap him with a dead fish. That engine is done! It's not even going to run in the water. And, if it does... Like Ski-d00 said... it's going to eat itself quick.

FYI... it's a 2-stroke

If it's super clean... and you want to rebuild an engine... then go for it. But I wouldn't pay more than $800 on a trailer for it.



OK..... Actually... Since the first mechanic was a MORON... go get a second opinion. Better yet... go buy an inexpensive compression tool, and check it yourself when you go to look at it. (if you own a 2-stroke Ski... a compression tool, and pop-off tool are mandatory)

 

[Dr Honda]

Oh... and yes.. he's right. +200 hr's, and low compression... it's going to need a full engine. On some of the smaller engines (720's and down) you could get away with a top end... but I have a feeling that you will do a top-end, and the crank will let go.

 

[OutlawBiz]

Oh MY F'ing G*D !!!!!!

a real seadoo mechanic said that !!!

Go back and slap him with a dead fish. That engine is done! It's not even going to run in the water. And, if it does... Like Ski-d00 said... it's going to eat itself quick.

FYI... it's a 2-stroke

If it's super clean... and you want to rebuild an engine... then go for it. But I wouldn't pay more than $800 on a trailer for it.



OK..... Actually... Since the first mechanic was a MORON... go get a second opinion. Better yet... go buy an inexpensive compression tool, and check it yourself when you go to look at it. (if you own a 2-stroke Ski... a compression tool, and pop-off tool are mandatory)

Hmmm...I actually called THREE seperate shops and they ALL said basically the same thing! They all said that 115 compression on both cylinders should be fine on a 2-stroke...closer to 140 on a 4-stroke. They all said it is a bit of a crap-shoot on a 2-stroke...could go anytime, but may be just fine too!? They said to take it for a ride and if it appears to have good power/acceleration, most likely going to be ok.

Was also told that a top-end rebuild woudl be $300-$500. Bottom if crank is bad= new motor based on ski's value.

Seller is asking $2500 for ski w/ single trailer...