Another leak.

[Larry1971]

Another day, another leak.

Been getting a little bit of white smoke or steam from the engine bay after running for a while. I've read it might be the head gasket, but noticed this wet patch under the engine today.

What could be causing this leak?

 

[kydirtscooter]

4.6 V8 it looks like. How are fluid levels? Is it a sweet smell or does it smell oily?

If it is sweet, I Would say leaking from the coolant passage at the back of the engine that the intake manifold covers. The glass fiber and nylon absorbs moisture over time and cracks eventually staring to seep coolant under pressure. The ports are on either side of the front and back of the engine. Could also be the heater transfer pipe under the intake draining into the valley. Is your valley dry?

Do a cooling system pressure test to eliminate cooling system if you think coolant.

 

[Larry1971]

4.6 V8 it looks like. How are fluid levels? Is it a sweet smell or does it smell oily?

If it is sweet, I Would say leaking from the coolant passage at the back of the engine that the intake manifold covers. The glass fiber and nylon absorbs moisture over time and cracks eventually staring to seep coolant under pressure. The ports are on either side of the front and back of the engine. Could also be the heater transfer pipe under the intake draining into the valley. Is your valley dry?

Do a cooling system pressure test to eliminate cooling system if you think coolant.

Yes, it's a 4.6 V8. The coolant is just under minimum line. I'll top it up tomorrow. I've noticed a burning smell but can't tell what it is. It's not sweet, more like burnt rubber or something rancid. I get a little (guess it could be exhaust smoke) from under the hood after running. I don't know much about engines, so I'm not sure where the valley is.

 

[kydirtscooter]

Sounds more like oil if it isn't sweet.

Wipe a little off the pan and put it on a piece of paper. Coolant will evaporate after a few days, oil will not. You could also wipe some off on your finger and then put it in a glass of water. If you see a rainbow like sheen then it is oil.

Next thing to check if it is oil would be valve cover gaskets, can you see if the engine is damp from the valve cover down or does it start lower? From your smoke symptoms,
it would probably be oil dripping onto the manifold. The seals dry up and crack the seep oil.

The earlier modular engines 4.6/5.4/6.8 had an oil weep between the head and block but that wouldn't really burn off and that was back in 97.

 

[Larry1971]

Sounds more like oil if it isn't sweet.

Wipe a little off the pan and put it on a piece of paper. Coolant will evaporate after a few days, oil will not. You could also wipe some off on your finger and then put it in a glass of water. If you see a rainbow like sheen then it is oil.

Next thing to check if it is oil would be valve cover gaskets, can you see if the engine is damp from the valve cover down or does it start lower? From your smoke symptoms,
it would probably be oil dripping onto the manifold. The seals dry up and crack the seep oil.

The earlier modular engines 4.6/5.4/6.8 had an oil weep between the head and block but that wouldn't really burn off and that was back in 97.

Thanks for the suggestions. I'll try tomorrow. I don't think I have any wet patches under the hood, but I'll take a good.

 

[kydirtscooter]

For valve cover you may have to look through wheel well opening on both sides. You can also turn your phone to video, turn the light on and record sticking the phone in places. I do that a lot since it hard to see.

 

[Larry1971]

For valve cover you may have to look through wheel well opening on both sides. You can also turn your phone to video, turn the light on and record sticking the phone in places. I do that a lot since it hard to see.

I had a look today (it was raining yesterday so everything was wet), These are from the drivers side. I see a wet patch on the far right, and a little dampness on the rest. Does it look like the gasket is going?