Every couple of months I have a small puddle of coolant below the engine and I can't find where it's coming from. Would it be ok to use some type of coolant stop leak that's on the market. Any advice will be greatly appreciated.
Coolant leak
- Thread starter Ronald Roman
- Start date
Don't you hate 20 questions.....
Is this after engine use?
Do you have a coolant expansion tank on the engine?
Is there a small hose just below the coolant cap? Could the coolant be coming from this hose? When the pressure builds up in the coolant system (heat expansion) the cap releases the pressure and a small amount of coolant may escape via this hose. - No problem. Unless you have an over heating issue - engine is running hot.
Is there any coolant leaking from the "fresh water pump" on the engine when running? If this is where you have a leak then you need to replace the seal on the pump. --- Big Problem. Fix immediately.
Is this after engine use?
Do you have a coolant expansion tank on the engine?
Is there a small hose just below the coolant cap? Could the coolant be coming from this hose? When the pressure builds up in the coolant system (heat expansion) the cap releases the pressure and a small amount of coolant may escape via this hose. - No problem. Unless you have an over heating issue - engine is running hot.
Is there any coolant leaking from the "fresh water pump" on the engine when running? If this is where you have a leak then you need to replace the seal on the pump. --- Big Problem. Fix immediately.
I'm assuming it's a Yanmar? I think most have an expansion tank for the overflow. If it is the closed system pump they a lot easier to change the pump then repair it.
I wouldn't use a radiator stop leak on any marine diesel if I were you, unless it was a last ditch effort to keep an engine running until a rebuild or replacement. That said, as we are in that position right now, use a very little bit if you need to. DO NOT use it until you have identified the leak! We have weeping freeze plugs that are inaccessible until we rebuild, so that's our excuse, but we can monitor when the leak stops. It will plug up the fresh water system if you use the whole radiator stop leak container.
Please don't ask me how I know or how many hours we spent rectifying THAT mistake.
Please don't ask me how I know or how many hours we spent rectifying THAT mistake.
I wouldn't be worried about plugging up the system with a stop leak product in a boat engine, better to have the leak stopped or slowed down then to let it run dry and overheat the engine.
Wouldn't you regret dumping goo into your coolant system if you later found out your problem was simply a loose hose clamp, or worn out water pump and that stuff did you no good? If you don't have the will or inclination to fully inspect your motor for the leak location just keep topping up and mopping up until the urge hits you. Small puddles don't justify leak stop goo.
I chased an AF leak in my Yanmar 2GM20F for a while. Some leaks were easier to find than others.
My filler cap neck, which bolts to the HX, developed a leak around the gasket. Oddly, I was losing AF well below the filler neck, when the engine was not used. Eventually regasketed the neck, and solved that part.
Replaced the HX cap.
Checked all around the T-stat housing, water pump weep hole. Did not find any leaks.
Checked all of the little drain valves and tightened them.
Checked all of the hose clamps and tightened them (many were loose).
Other than the filler neck, I could not really find a leak, but I am no longer losing AF.
I certainly would NOT put any stop leak in the engine. The little channels in the engine block and head need to flow to keep the engine cool.
I am no mechanic, but I can't imagine that would be a good fix.
Greg
My filler cap neck, which bolts to the HX, developed a leak around the gasket. Oddly, I was losing AF well below the filler neck, when the engine was not used. Eventually regasketed the neck, and solved that part.
Replaced the HX cap.
Checked all around the T-stat housing, water pump weep hole. Did not find any leaks.
Checked all of the little drain valves and tightened them.
Checked all of the hose clamps and tightened them (many were loose).
Other than the filler neck, I could not really find a leak, but I am no longer losing AF.
I certainly would NOT put any stop leak in the engine. The little channels in the engine block and head need to flow to keep the engine cool.
I am no mechanic, but I can't imagine that would be a good fix.
Greg
Check the engine water pump, it has a weep hole at the bottom behind the pulley. If the puddle is forming directly below the pump it is a good indication that the source is a busted seal at the pump. Just feel to see if the underside of the pump is wet. The fix for a leaking pump is to replace it and it should be done while the leak is still small as it will continue to worsen until it results in an overheating engine. Listen to the pump to see if the bearing is getting noisy as a fluid leak past the seal tends to damage the bearing, collapsing the shaft and perhaps releasing the belt from the pulley. No I would not advise using a stop leak as it will not work on a turning shaft and may cause blockage in the heat exchanger. But before you tear into the pump make sure that all the hoses and clamps are in good shape and dry.
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Oil absorb pads are what we use under both engines and I'd think they were a lot easier to clean up than wet TP.
And yet after I'd just posted about how stop leak caused me so much grief, you posted, "I wouldn't be worried about plugging up the system with a stop leak product in a boat engine". Hum.....
And you expect everyone to believe because you had a bad experience using stop leak, everyone else to going to have a problem as well? How naïve of you . These products are used daily all over the world, maybe it was your lack of knowledge in using such products and not the product itself, but one will never know for the lack of info you provided in your first post.
Oh, and about the "Stupid is as Stupid does" comment, I guess if one doesn't agree with you, they are stupid, fair enough!
I didn't post the "Stupid is as Stupid does" comment. I believe some other members were referring to your post.
Auto parts stores can rent you a test kit that allows you to pressurize your coolant system so you can find out if there is a leak (decaying pressure) and hopefully allow you to find it as it should keep leaking while pressurized without the hazard of the engine running while you are snooping around. It is just a radiator cap the is attached to a pump and a pressure gage.
I am the member who wrote the quip.
I have used stop leak for old gasoline engines. I agree with what Capta stated. In general the channels of Diesel engines through which coolatn flows tend to be smaller than gasoline combustion engines. Marineized engines are especially vulnerable because of the frequent occurrence of rust in their systems. While it is possible that you could use such product in an emergency. I feel suggesting it's use as a viable resource for the type of problem of the poster is ill advised.