951 Reliability/Common Problems

[merc1100sc]

Hello all. I just came across this forumn by searching for common problems with 951's. I am looking at a 2000 Sportster with the 951. I've owned a handful of 720's & 787's in the past but have always strayed from the 951 due to various negative feedback many years ago. Can anyone tell me their experiences with these motors? Are they as bad as I remember hearing? Keep in mind this was back when the GSX Ltd 1st came out. I am assuming improvements have been made since.

Thanks.

 

[El Toro 33809]

Welcome to the forum. You will hear lots of comments about the 951 engines. A few swear by them. Many swear at them. They are putting out high HP for a 2 cylinder engine. I have read that if treated properly they are just fine. I believe that a member by the name of SabrToothSqrl really likes that engine and could probably give you good tips on the engine.

 

[CaptSteve]

I have a 951 in my 2001 Sportster that I have owned for three years now. It is the original engine and has about 170hrs on it. So far the only problem I have had was a leaking vacuum line. The engine has 150 psi compression in both cylinders, starts up easily whether hot or cold. It still has the oil pump hooked up and there is virtually no smoke when starting or accelerating.

Since I do a lot of my boating in the ocean, I rarely run it WOT. After I get on plane, I back it down and I am cruising along at around 5500 RPM, which gives me about 30mph with two people on board.

I use Seadoo XPS full synthetic oil and only have to clean my Rave valves once a year. I change oil and fuel filters annually, along with the spark plugs.

I think it is a great engine so far, but this is the first Jet Boat I have owned.

 

[merc1100sc]

Thank you for the replies everyone. Sounds like this motor shouldnt be all that bad. And, if I end up purchasing a boat with this motor and it fails I'm sure I can rebuild it. I've done a few 787's in the past. I don't have my heart set on this particular boat. I actually want a speedster if I can find one reasonable. I actually have my eye on a 99 speedster sk that I plan to go look at soon.

 

[Dr Honda]

The 951 was a hunk of junk when it was first released. The 1997-1/2 engine ate itself in a few hours. They basically took care of the issues in 98.

With that said... they still dont' have the life expectancy of the 800 and smaller engines. On average... you get about 400 hours on the 800 and smaller engines... and only 200 to 300 (max) on the 951.

Obviously, there are exceptions to that... but with general use/maintenance... that's what you get. SO... if you are thinking of buying it... take it for a water ride to make sure things work as they should... and take it to a dealer to have the the total time checked. Oh.... and finally check the compression. 135 is a new/rebuilt engine... anything over 120 is OK.

 

[Stevego]

check the compression. 135 is a new/rebuilt engine... anything over 120 is OK.

So the 951 is only 135 psi when new not 150 psi like the 787's?

 

[Dr Honda]

So the 951 is only 135 psi when new not 150 psi like the 787's?

Correct. That's one of the things they changed. The 951... for general usage... couldn't take 150 psi static compression. For 2 years, they made an RXX and it had the more powerful 165 HP version of the 951.. but it was for "Racing" and they didn't have to warranty the engine.

 

[Stevego]

Good to know! I just sold my Sportster and it had around 130psi. I thought it was getting tired and worried that it would die on the new owner. Now I know it is fine! Thanks DOC :thumbsup: