Complete rebuild??? HELP please

[Jared]

Today was a bad day... I was out on the lake when the left engine started to run unusually rough. It has been ruunning rough for a few months now but this time the engine seemed like it was about to knock itself off the mounts, and it was making a loud knocking noise. I turned it off and checked the plugs. They were dark brown, which i believe means that they i am not running too lean. I put them back in and started it up again with the same problem as mentioned above. I turned it off again and this time when I tried to start it, all I got was a click. I took the output shaft behind the motor and tried turning it by hand and it had significant resistance, almost like it was jammed or something. I ended up limping back to the dock with my good engine and, an hour and a half later, loaded it back on the trailer and went home. When I got it home I took the carburator off. Don't ask me why because I don't know. And beneath the carb in the port that goes into the engine was a peice of metal about 1/2" long by 1/8 inch wide. Red flags went off in my head and I am thinking that I have very big problems. If I have bent the crank or a piston that would explain the rough unbalanced motor that wants to bounce off the mounts. Here is my question..... Does this mean a complete rebuild? SBT sells new engines for $750. I cannot take the boat to my seadoo dealer because they are very very dishonest and shady. Any ideas, opinions or help would be greatly appreciated. By the way it is a 98 sporster 1800.
P.S. how hard is it really to pull the entire engine. I am mechanically inclined and have rebuilt my motor in a 69 f100 pickup, but never a 2 stroker.

 

[Jared]

Bump... anyone?

 

[2001Challenger2000]

I'd do the SBT swap, if your block is a good core, you'll come out cheaper and better in the long run to do a swap than building yours.

First you need to make sure you find out the inital problem as to why your engine died the first time.....oil starvation or what? Find that problem, fix it, and then install the SBT crate, you can do it no problem if you can rebuild a truck engine, you can do this also. Just take notes if you have to where stuff ges and how........your old engine just might have been at that point of going and went and everything is OK, just do a swap out at this point.

Rotax engines are a pain, and the mercury engines are a bigger pain to t-shoot, but seem a bit more dependable. I have owned both, and have a mercury now thats down, hoping to be hitting the water this week though.

 

[Jared]

Thanks for the advice... The engine is over 10 years old and has never sounded the same as the other one ever since I have owned it (3 years), and recently it has gotten much worse. I have been doing a little research and am just wondering if the new engine will come with a gauge/tool to align the motor. Anyone ever replaced engine please give advice. I know you need to find TDC then go from there, I just am not sure how to time it (tools or gauges necessary).

 

[2001Challenger2000]

I believe you'll need the alignment tool for reinstallation.

 

[pincusa]

First where did the metal piece that you found come from? That might help find the cause of the issue

Check to see if you have a twisted crank. Pull the plugs, put a gauge down the plug hole until you get TDC on that piston and then mark the fly. If that's not BDC for the other piston, then the crank is twisted.

What is the compression for both pistons? That would also cause an uneven idle

Or you can pull the engine and drop in a rebuilt if your pockets are deep

 

[pincusa]

I have been doing a little research and am just wondering if the new engine will come with a gauge/tool to align the motor. Anyone ever replaced engine please give advice. I know you need to find TDC then go from there, I just am not sure how to time it (tools or gauges necessary).

It won't come with you. You can rent one from SBT or other places, or take it to the dealer. It's not a hard job, but you need the tool to do it

 

[Jared]

I don't know how to check for that if I cannot turn the drive shaft. Same with the compression. When I first got it home I was able to turn it almost one full turn, but now it acts like it is binding on something. I am not sure where the metal came from, that is why I am pulling it out, to open up the bottom end and check things out. No, my pockets aren't deep, I just have never rebuilt a 2 stroker before. I will try to finish pulling out the moter next week and let you know what I find. I've tried to post pics, but I am computer retarded.

 

[pincusa]

Before you pull the engine out, pull the head. It's just the bolts going through the cover and the whole thing will pull off. Once you're there, you can easily see the pistons and see what's happening on top of the engine.
I'm hoping that a rave valve might have broken off, and the pieces are inside the piston. If the walls aren't scratched, and everything looks OK, you can replace it and keep going. If it's the bottom end that's gone, then it's easier to just get a reman as the bearings and rods all all pressed onto the crank and are a pain to replace.

What I fear is your oil pump may have gone, and the engine was running w/o oil. In which case you'll also damage the reman engine as you reuse your old oil pump.

As for pulling the engine, pull the pump out so you can remove the drive shaft. Disconnect the exhaust, electrical lines and fuel, and pull it straight up. Job isn't hard, but the working conditions make it hard. Let us know what you find.

 

[Jared]

Got the pump, exhaust, electrical, carb, and oil pump off. Here is what I found .... Looks like wrist pin bearings mixed in with junk metal. There is no rave valve, by the way. I am taking the heads off this afternoon and will give update

 

[Jared]

OK heads off and it doesn't look pretty... most of the damage is on the piston at the front of the engine...

 

[Jared]

I am having some problems with the fly wheel. I have got the nut off, but can't get it to pull off. I've tried using a fly wheel puller with an impact driver, but nu luck. Can or should I try using a little heat?