1988 Suzuki DT55 Seized up?

[pcmartinson]

I had just replaced the cooling water sensor and the motor was running fine. I went about 2 miles and it sounded like I bottomed out, but I was in 30 feet of water. When I attempt to restart it, nothing moves, it just makes a sound like a single "knock". Any ideas what may be the problem?

 

[jim dozier]

Re: 1988 Suzuki DT55 Seized up?

If you drop the lower unit you'll know whether the problem is in your gearcase or the engine. Most likely the latter. You can pull the spark plugs and look inside but a seized piston may not show itself without further dismantling of the engine. Was the oil injection working on the engine or were you on premix? Had the engine been running well?

 

[pcmartinson]

Re: 1988 Suzuki DT55 Seized up?

When I pulled the spark plugs they looked fine. I was running on premix (and there was oil in the oil resevoir, because I was getting a faulty low oil signal because of the cooling water sensor, which I replaced). The engine was running fine. I had replaced the cooling water sensor last week because of the oil signal, but it was running great after that. But I only got about two miles before the engine seemed to seize up.

 

[pcmartinson]

Re: 1988 Suzuki DT55 Seized up?

This morning I pulled the plug on the lower unit to drain it so I could work on it when I got home and all that came out was about 1/2 quart of WATER!!?!?

 

[jim dozier]

Re: 1988 Suzuki DT55 Seized up?

In light of that new information I would again suggest that you drop the lower unit. Then you can determine whether it is the gearcase that is locked up or the engine.