Cold engine despite running for a while. Water entering bilge

[beruken]

So, 4 years a carb rebuild new exh/risers, thermo and housing, trim units, gimbal bearing, bellows shift cable, sei drive etc... everything seemed like go in the driveway. at the launch, i noticed water in the bilge and saw a leak from one of the risers between the boot and Y pipe. nothing major Noticed engine temp was not rising and it was dead cold. started hearing and seeing a stream in the back of engine compartment down below. I'm going to remove the drive and inspect everything to make sure it is tight and sealed. Cold engine possibly related to the leak???

4.3 l merc
1999 SR curry 190

 

[alldodge]

If it coming out around the bottom of the motor bell housing, it might be a core plug rusted thru or came out.

 

[beruken]

If it coming out around the bottom of the motor bell housing, it might be a core plug rusted thru or came out.

ok, yeah, I had a concern about one of those but they are located on each side of the block. I suppose I should see it with the muffs on too, no? would that be the reason the engine was cold ?? I can see an engine overheating but never getting warm, got me.

 

[beruken]

Just ran it with the muffs for about 10 in. Saw no water anywhere. engine temp did not break 115 and intake manifold was cold. top of risers were warm and area around the thermo housing. port exhaust water was splattering while starboard was more stream like. felt under the port Y pipe but did not feel any rust thru.

 

[alldodge]

This is your cooling system


Has a 4 port thermostat housing
Note how the thermostat and pieces are installed. If done incorrectly it could be bypassing.

That said since it only leaks when in the water, it's most likely a transom issue. Could be soft or something not installed correctly

 

[Scott06]

ok, yeah, I had a concern about one of those but they are located on each side of the block. I suppose I should see it with the muffs on too, no? would that be the reason the engine was cold ?? I can see an engine overheating but never getting warm, got me.

There are core plugs in back of block behind flywheel too

 

[beruken]

Update on this. Found the brand new never used but installed for 1 year, shift bellows torn in 2 places. Replaced. Checked thermostat for proper install.

 

[tank1949]

Just ran it with the muffs for about 10 in. Saw no water anywhere. engine temp did not break 115 and intake manifold was cold. top of risers were warm and area around the thermo housing. port exhaust water was splattering while starboard was more stream like. felt under the port Y pipe but did not feel any rust thru.

Make sure thermostat is working or/and installed. The engine needs to operate efficiently at a certain temperature range. If salter water motor, y pipe or core/freeze plug may have corroded through. Use a mirror as best as possible to see under motor. Pray motor didn't freeze during winter and you are just now discovering it. Check plugs for water, just to be safe, if all else checks out OK.

 

[beruken]

Make sure thermostat is working or/and installed. The engine needs to operate efficiently at a certain temperature range. If salter water motor, y pipe or core/freeze plug may have corroded through. Use a mirror as best as possible to see under motor. Pray motor didn't freeze during winter and you are just now discovering it. Check plugs for water, just to be safe, if all else checks out OK.

Thanks. I did open thermo to verify placed correctly and it was a brand new housing and thermo. Update is I put in the ocean and test ran it with same issue for about 20 min. opened her up to about 3500 rpm for a about 10 min and the temp gauge finally started to move, engine eventually reached 130 for a period, then finally came up after another while to 170. a bit high if I'm correct but engine compartment was finally warm and all components hot to the touch.

 

[cyclops222]

Sounds like the water is taking way to long to warm up. Thermostat is wrong one ? installed wrong ? Choke is wrong ? Missing a gasket under the thermostat ? Temperature gauge is in correct ? A little bit of some problems ?

 

[beruken]

So an update on this saga. After opening new thermo housing again I noticed quite a bit of rusted metal chips in my manifold and cleaned it out. Did this a last year as well when I replaced the housing and stat. Also put in another thermostat from the automotive store. Problem seems to be solved but the determination of what was the cause is unknown. I did see those chips in the spring of the thermo and it also seemed some small bit was stuck in the ball. Can't attach pic but maybe time for a new intake manifold too.

 

[Grub54891]

Rust chips will be all over the cooling system. Inside the block also. Only way to get most of them out is to remove the core plugs and flush the heck out of the block itself.

 

[beruken]

So back to this thread for some updates. Having issue with the thermo again and the other day after returning home (without a temp reading all day) and flushing the engine, no water was coming out the exit ports rear of boat. Engine was still quite warm. Replaced temp sensor a couple days later and still no temp reading. Starboard riser was cold, Port hot. Removed drain plugs and water came out of everywhere it should. This time though, I could see the rear exit ports were wet so not sure how much, but suggested thermostat opened. When I shut of the engine, I did notice the temp gauge spiked to about 130 with just the key on but drops to nothing when engine is running. Out on the water it sometimes jumped up a bit and fell back. May just be a wiring issue, but that would have no bearing on how one riser is cold and the other very hot. Any thoughts why the two risers are different temps?

 

[Scott06]

So back to this thread for some updates. Having issue with the thermo again and the other day after returning home (without a temp reading all day) and flushing the engine, no water was coming out the exit ports rear of boat. Engine was still quite warm. Replaced temp sensor a couple days later and still no temp reading. Starboard riser was cold, Port hot. Removed drain plugs and water came out of everywhere it should. This time though, I could see the rear exit ports were wet so not sure how much, but suggested thermostat opened. When I shut of the engine, I did notice the temp gauge spiked to about 130 with just the key on but drops to nothing when engine is running. Out on the water it sometimes jumped up a bit and fell back. May just be a wiring issue, but that would have no bearing on how one riser is cold and the other very hot. Any thoughts why the two risers are different temps?

The risers are always a little different depending on how the boat is leaning .
130 is cold for an engine thermostat is staying open

 

[Lou C]

With raw water cooled engines it is pretty common to get rust flakes stuck in the thermostat and then the engine will run cool until you get it up on plane. One of the drawbacks to raw water cooling, there will always be more rust, particles, sand, silt in the engine than if you had closed cooling in which case the engine would stay pretty clean inside as long as the AF was changed when needed. I have actually changed a couple thermostats and cleaned out that water passage in the intake with the boat on the mooring a few times due to the same problem.

 

[beruken]

Thanks. I removed my risers 1 season old and replaced the gaskets with the one that has open ports on all sides. I recall doing my due diligence to determine which version was the proper one and had put the one with the small hole one side. We'll see. Pulling the thermo again to see how much rust in there though I only used it about 6 times last season and flush everytime. !$%^ salt water

 

[beruken]

The risers are always a little different depending on how the boat is leaning .
130 is cold for an engine thermostat is staying open

I replaced the engine temp sensor. I guess there is a different sensor for water temp. Likely needs replacing too, it measures 600+ ohms. I assume that one sends the temp signal to the gauge and the engine temp trips an alarm.

 

[Scott06]

I replaced the engine temp sensor. I guess there is a different sensor for water temp. Likely needs replacing too, it measures 600+ ohms. I assume that one sends the temp signal to the gauge and the engine temp trips an alarm.

No only temp sensors are the sender for the gauge and the alarm over temp switch . Both are in the thermostat housing