How can you tell for sure that water if flowing into the engine?

[valkyr]

Ok I'm paranoid and all. I admit it.

I want to make sure water is flowing correctly in my system while its on the muffs. What is the best way to do this?

I thought about unhooking one of the coolant hoses to see if water comes out when its running.

Also I'm not 100% positive the temp guage is working...all the other guages seem to be, but the temp isn't rising. I let it run on muffs about 3-5 minutes but being extremely paranoid here, I didn't want to take a chance that the coolant wasn't flowing.

Good way to check the temp guage?

Thanks for any and all help/suggestions.

 

[WillyBWright]

Re: How can you tell for sure that water if flowing into the engine?

Wutcha got?

MerCruiser thermostat housings (where the temp sender is) requires a special gasket that has a pair of rivets that maintain continuity between the block and housing. A lot of people use plain automotive gaskets to get by cheap and lose that electrical ground connection. Result...the temp gauge never budges.

 

[Bondo]

Re: How can you tell for sure that water if flowing into the engine?

Ayuh,........

And it's Pretty Easy to Test the Gauge,........

Just Disconnect the wire from the Sending Unit,+ Ground it out.......

The Gauge should Peg Out to Max..............

 

[njlarry]

Re: How can you tell for sure that water if flowing into the engine?

I keep a constant eye on the water coming out of the exhaust when on muffs and frequent checks of the thermostat housing and risers with a hand held infrared thermometer when in the water. I also feel the hoses for equal pressure and temp.

 

[WAVENBYE2]

Re: How can you tell for sure that water if flowing into the engine?

I know it sounds silly , but I was worried about that too, every where in the book in bold letters DONOT RUN ENGINE WITH OUT WATER . So I would sqeeze the hoses and felt water rushing through, my mind was at ease after that. Simple but it worked for me.

 

[WAVENBYE2]

Re: How can you tell for sure that water if flowing into the engine?

I know it sounds silly , but I was worried about that too, every where in the book in bold letters DONOT RUN ENGINE WITH OUT WATER . So I would sqeeze the hoses and felt water rushing through, my mind was at ease after that. Simple but it worked for me.

If I wasn't frustrated ,I felt like nothin was accomplished

 

[bruceb58]

Re: How can you tell for sure that water if flowing into the engine?

Loosen the clamp on one of the hoses going to the exhaust manifold. Once the engine is started, pull it off to see if water is flowing and then quickly put it back on.

 

[clint s]

Re: How can you tell for sure that water if flowing into the engine?

Also remember if you are running on a well like me the cold water temp coming in is like 50* causing the engine to runn much cooler. when I run off my muffs I usually have to run it a long time to get the stat to open if ever.

 

[valkyr]

Re: How can you tell for sure that water if flowing into the engine?

Update:

its a '88 Mercruiser 454 7.4L (similar pic of engine attached).

Checked the water coming out of the exhaust while on muffs and good supply of water coming out and the water was warm (bath water warm, not too hot, very comfortable).

Bond-O: As I'm still learning my way around this engine, where is the sending unit? :redface:

Also, looking at the below picture, hose A is warm/hot after engine running, but hose B seems cool. Is that normal or should I be concerned that water isn't getting to the that side of the engine, or maybe that hose is something different? I think hose A comes off the water pump on this engine if I'm not mistaken?

Thoughts?

 

[valkyr]

Re: How can you tell for sure that water if flowing into the engine?

No responses? I know thats a weird picture, but just assume its 1 engine from 2 different angles where hose "A" is on the left and hose "B" is on the right when you're looking at the engine.

 

[QC]

Re: How can you tell for sure that water if flowing into the engine?

Hose B is the supply from the lake . . . Should be cool A is warm water recirc from engine. One thing you should do while running is carefully touch your exhaust manifold risers. They will be slightly different side to side as flow is not perfect, but you should be able to touch them briefly (be careful). This will indicate if you're getting flow from your seawater pump. As long as your recirculating (engine water pump) is working and the thermostat is opening, then you are getting flow through the engine too. If A is really hot, then the thermostat probably isn't opening, I can feel mine warm up and then cool a little as the Thermo opens . . .

Here is a diagram that probably covers your engine. The sending unit is probably where plug #2 is and you should be able to follow the flow from the lake (Hose 9) to the oil cooler (#10) to the Thermostat housing (#11 = Hose B). Hose # 12 is your Hose A. #14 and #15 go to the manifolds and out to the lake again. Not sure what happened to hose #13 . . . Maybe it was unlucky

 

[valkyr]

Re: How can you tell for sure that water if flowing into the engine?

Here is a diagram that probably covers your engine. The sending unit is probably where plug #2 is and you should be able to follow the flow from the lake (Hose 9) to the oil cooler (#10) to the Thermostat housing (#11 = Hose B). Hose # 12 is your Hose A. #14 and #15 go to the manifolds and out to the lake again. Not sure what happened to hose #13 . . . Maybe it was unlucky

Where is "HERE"?

 

[QC]

Re: How can you tell for sure that water if flowing into the engine?

Ooops:

http://media.stemtostern.com/defaul...m/LSDATA/LSDATA_FULL/CRUISER\821723.92\16.GIF