Bought this 1985 Suzuki DT25 as a project with head removed, 3 head bolts broken off in block.
Machined head with sandpaper and glass, replaced head gasket, replaced thermistat (old one wouldn't open), new water pump impeller and water pickup tube grommet, cleaned carbs.
Drilled out head bolts and cleaned threads. Got off center with 2 of them and drilled into water jacket. Installed new head bolts with sealant.
Engine runs great, with good compression on all 3 cylinders. Only trickles water out of exhaust and nothing from pee hole and overheats.
Ran engine with lower unit off and water hose hooked to pickup tube. Engine runs cool with good pee stream.
Flushed water passages both ways, up and down through thermistat opening, no debris found. Old impeller was intact before replacing it.
Looking for ideas how to run down this problem. Is it a still unsolved problem with water pump? leaking water pick up tube up high towards head? Can I just pull out pick up tube to inspect or do I need to remove power head? Hole corroded thru water jacket?
Any chance leaking exhaust gas is pressurizing water jacket, keeping cooling water from getting up to head? When running with thermistat removed, water does not get up to thermistat housing opening.
Any ideas, direction to go from here, would be appreciated. Thanks
Machined head with sandpaper and glass, replaced head gasket, replaced thermistat (old one wouldn't open), new water pump impeller and water pickup tube grommet, cleaned carbs.
Drilled out head bolts and cleaned threads. Got off center with 2 of them and drilled into water jacket. Installed new head bolts with sealant.
Engine runs great, with good compression on all 3 cylinders. Only trickles water out of exhaust and nothing from pee hole and overheats.
Ran engine with lower unit off and water hose hooked to pickup tube. Engine runs cool with good pee stream.
Flushed water passages both ways, up and down through thermistat opening, no debris found. Old impeller was intact before replacing it.
Looking for ideas how to run down this problem. Is it a still unsolved problem with water pump? leaking water pick up tube up high towards head? Can I just pull out pick up tube to inspect or do I need to remove power head? Hole corroded thru water jacket?
Any chance leaking exhaust gas is pressurizing water jacket, keeping cooling water from getting up to head? When running with thermistat removed, water does not get up to thermistat housing opening.
Any ideas, direction to go from here, would be appreciated. Thanks
