Suzuki 25hp cleaning water passages

[Jason123]

Hi Guys, I have a Suzuki oil injected 25hp 3cyl 2 stroke 1990 model that won't pump water. I got the motor about a month ago and was told it hadn't been started for a year or so. I fired it up and it ran ok but didn't pump water and got hot. I changed the water pump that looked a bit rough but it still wouldent pump water. I removed the thermostate and started it and still no water. I removed the lower unit again and with a hose attatched to the tube and a lot of preasure I got water out the pee hole but not the other larger hole. I pulled the powerhead off and removed the plate at the back where the spark plugs are (is that the head?) and the plate on the left hand side of engine that gives a side on view of the pistons. Several bolts broke off while doing this but i got it off. It all looks discoloured. Preblem is I don't realy know what i'm looking at and I dont know the exact path the water is meant to flow. There don't seem to be any small holes where it could get blocked except for under the left side plate and I think those small holes go to the piston and are mabe for fuel or oil? Any ideas on that to do to clean out the water passages and also exactly where they are would be great. Please help. Thanks.

 

[Jason123]

Re: Suzuki 25hp cleaning water passages

I put the exhaust plate on and remounted the power head after 1st ensuring I had enough water flowing through the water tube. With the head off I could see water coming out of 2 holes at the bottom of the engine. The there were many other areas that water wasn't coming from. I initially thought they were blocked, but it later occoured to me that mabe the water came out through the 2 bottom holes and then flowed back through the other holes. Does this sound right???
I ran my hose directly to all of the holes at the back of the engine (under the head) and water came out the tell tale and large hole in the shaft when I attatched the hose to any of the holes.
I think i'm ready to free the broken off bolts, buy some new gaskets and reassemble.

 

[James R]

Re: Suzuki 25hp cleaning water passages

You dont say what year your motor is. However a recent experience with a 1988 DT30, which is the same motor as the DT25, showed bits of impeller lodged in the water cavity where the water tube enters the block, scoring of the pump base plate and housing and a bad impeller. All of these things contributed to bad water flow. Replacement of all the bad parts and removal of the impeller bits made the water system function correctly. Yes there are two holes in the bottom of the block suposedly for exhaust gas cooling.

 

[Jason123]

Re: Suzuki 25hp cleaning water passages

Hi James and thanks for the reply. It's a 1990 model and it's the DT25C (3cyl 2 stroke). Sorry for leaving that out. I'm gonna start putting it back together again. That bit at the top of the water tube is clear. Nearly all the bolts broke off then removing the exhaust cover plate on the side of the engine. I purchased a propane tourch and some multi grip plyers. Am I going to blow myself up heating those bolts with a tourch? They are right near the external fuel bowl. What is the best technique for removing bolts with heat?