How Much Damage Have I Done to My Engine?

[Cardo]

So I've checked over the engine and the engine itself seems fine. Impeller was intact and aside from needing to top up the coolant a little, it looks like the engine didn't suffer any damage.

However, I discovered a small dribble coming out of the joint between the exhaust and the water trap. I took off the exhaust and it looks like the plastic inlet into the water trap may have warped slightly. However, it doesn't look bad. So I put the exhaust back on and tightened it up. The dribble has gone down to a drip every 20s or so, less when the engine is revved up.

Thoughts? Is this acceptable? Could I put some exhaust paste on there to seal up any gaps? Or does the water trap need fixing/replacing?

 

[tudorsailor]

My exhaust is meant to be dry

Interesting thread. I have a dry exhaust so that cooling sea-water goes out under the hull and the exhaust is only gas. Much quieter but I will not know if the impeller has failed until the engine overheats!

I had the opposite problem. After having work done in the UK the water outlet sea-cock was left closed by the yard, so then I did have a wet exhaust!

The delivery crew thought a wet exhaust was normal of course, so delivered the yacht from UK to Spain - with lots of motoring - with the water coming out the exhaust. No idea what problem this might have caused. Any ideas?

TudorSailor

 

[vyv_cox]

The delivery crew thought a wet exhaust was normal of course, so delivered the yacht from UK to Spain - with lots of motoring - with the water coming out the exhaust. No idea what problem this might have caused. Any ideas?

It's a complete unknown to me. How does the cooling water get to the exhaust pipe if the valve is left closed? Presumably the exhaust is stainless steel of some sort, maybe a grade that resists heat better than 316? In which case it should be OK but I would check it for cracking and salt growth before going too far with it.

How does the exhaust cope with engine movement? If there is some sort of flexible hose this should be checked very carefully if seawater has come into contact with it.

 

[david_bagshaw]

So I've checked over the engine and the engine itself seems fine. Impeller was intact and aside from needing to top up the coolant a little, it looks like the engine didn't suffer any damage.

However, I discovered a small dribble coming out of the joint between the exhaust and the water trap. I took off the exhaust and it looks like the plastic inlet into the water trap may have warped slightly. However, it doesn't look bad. So I put the exhaust back on and tightened it up. The dribble has gone down to a drip every 20s or so, less when the engine is revved up.

Thoughts? Is this acceptable? Could I put some exhaust paste on there to seal up any gaps? Or does the water trap need fixing/replacing?

seal it with sikkaflex, just the job for exhaust hose problems. I use it for stainless to a silicone rubber jobbie, that is difficult to get gas & water tight.

 

[david_bagshaw]

Interesting thread. I have a dry exhaust so that cooling sea-water goes out under the hull and the exhaust is only gas. Much quieter but I will not know if the impeller has failed until the engine overheats!

I had the opposite problem. After having work done in the UK the water outlet sea-cock was left closed by the yard, so then I did have a wet exhaust!

The delivery crew thought a wet exhaust was normal of course, so delivered the yacht from UK to Spain - with lots of motoring - with the water coming out the exhaust. No idea what problem this might have caused. Any ideas?

TudorSailor

None.

if it is similar to the halyard design the dried exhaust pipe and the wet will be the same size. the water separation takes place at the top of a baffled gooseneck, so if the water doesnt drain, it washes by.

I installed a halyard one with the onan genny I fitted some years ago. It has always suprised me this kit is thought of only as a genny installation. Shure quietens the exhaust. I tried closing the drain valve during commissioning trials, had no detrimental effect on engine output, but was noiseier sp?.

 

[tudorsailor]

None.

if it is similar to the halyard design the dried exhaust pipe and the wet will be the same size. the water separation takes place at the top of a baffled gooseneck, so if the water doesnt drain, it washes by.

I installed a halyard one with the onan genny I fitted some years ago. It has always suprised me this kit is thought of only as a genny installation. Shure quietens the exhaust. I tried closing the drain valve during commissioning trials, had no detrimental effect on engine output, but was noiseier sp?.

Thanks for the reassurance. I agree that the engine/exhaust is quiet. Once running, it is incredibly quiet from the cockpit.

I do get occasional shouts from well-meaning souls when motoring out a marina, to let me know there is no water coming out of the exhaust

TS

 

[Cardo]

seal it with sikkaflex, just the job for exhaust hose problems. I use it for stainless to a silicone rubber jobbie, that is difficult to get gas & water tight.

Ah, brilliant. Soon the boat will be held together with nothing but Sikaflex!

Thanks for the tip.

 

[Tomahawk]

If it starts from cold

Then you have probably got away with it... Aftrer all that is what those alarm is for..

However.. Keeps closeeys on the FW header tank... A common problem after an overheat is that you damage the head gasket and it vents gas into the cooling system... Not enough to stop her running.... But just enough to pressurise the cooling water...

If you find that the cooling water is dropping... Run the engine from cold with the top off the filler cap... The symptom is bubbles in the cooling water...

In that case it is a head gasket job.... Which can possibly be done in situ depending on how much space you have around...


Good luck

 

[david_bagshaw]

Ah, brilliant. Soon the boat will be held together with nothing but Sikaflex!

Thanks for the tip.

Was told that one by, either by halyard,or Sabre when having trouble sealing the 5 inch flex section at the spray nozzle.

Tudor sailor, you just have to keep a weather ear out for the tone change when it goes dry & a dam good regular look at the temp gauge !

Wind has dropped here in AMS and it has been sunny, & where have I been.......Fuel Tank cleaning. Drat. However hoeaagarden grand cru in hand now. Excellent stuff.