Chill over my back: What a white smoke from carb may ultimately mean ?

SeaLord

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Oct 29, 2013
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My 5.7 Gla 2001 had a total of 100 hrs when i bought it 12 months ago. inspector run a compression test with good result. Since then boat has crossed the ocean to a very warm and humid indian ocean place.
I started maintaining it assuming it was not done for very long time. Boat restarted in late december (workmanship difficult to find in here) and added another 30 hours. I have been keeping the boat partly dry and partly at mooring (max for a week 10 days).
At mooring a couple of times has rained very heavily and the day after the engine woudl not start. I discovered some loose cable (how easy they become loose !!!) and last time engine started after cleaning all cables leading to the engine. It normally runs fine but I kind of suspect that my result are more by coincidence than because I hit the good cure.

I noticed that, when it was not starting, a white smoke came from the carburetor ( through the flame arrestor ) not always and never when eventually the engine started
I also notice that one of the manifold base is rusting. Should I fear a leakage in the cylinder so I am about to discover the engine is seriously damaged ?


Thanks
 

Augoose

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

Solve your wiring issues so the engine gets good voltage to start strong every time - weak starting or failed starting can cause excessive fuel to collect in carb mixed with your moist climate resulting in white smoke- especially since the smoke clears after starting - likely manifolds are fine. Also verify your timing and check for good spark. A weak battery, weak ignition system or in correct timing are all issues which can cause the symptoms you are facing.

As for your manifold, poke around with a screwdriver in the rusty areas and examine whether its surface rust or whether you have structural issues. Take a wire brush and clean the mating surfaces of the manifold and inspect for gaps or holes.
 
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SeaLord

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

Thank you very much.
I would proceed for some inspection of the manifold and elbows since if there is a problem I understand I may not get some other alert before the disaster.
I tried to look on the internet but it seems to be no way to detect if a manifold has been excavated by rust to the point water may leak in to the gas channel and from there to find its way into cylinders.

Facts are: engine is 13 yrs old
only 130 hrs on it of which at least 70 in sweet water and at least 30 in salt water.
I do not know weather manifolds and elbows have been already replaced and when (may one usually tell from a detail n them ?)
Sailors say you should not expect more than 3 years of service.

Is there any safe way to tell when I should proceed with substitution ? I bought a full set when my boat left florida but I would hate to substitute them unnecessarily.

Thank you aga
 

Augoose

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

...I tried to look on the internet but it seems to be no way to detect if a manifold has been excavated by rust to the point water may leak in to the gas channel and from there to find its way into cylinders.
If your boat runs normally after starting with no smoke, your manifolds are likely fine. Pull the spark plugs - do you find any evidence of water in the cylinders? If your manifolds were failing the engine would let you know by knocking and eventually failing because the pistons are trying to compress/combust water.
Follow these directions to inspect your manifold -


Sailors say you should not expect more than 3 years of service.
That is absolute worst case IMO for saltwater and not flushing with freshwater after boating. Freshwater manifolds will go many years.

Is there any safe way to tell when I should proceed with substitution ? I bought a full set when my boat left florida but I would hate to substitute them unnecessarily...
Follow the above link and inspect your manifolds since you don't have a marine surveyor available where you are. If you are really concerned, remove your manifolds and do a full inspection - replace if necessary.
 
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jerryjerry05

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

Manifolds in salt water can last from 14-20 years.
A defective manifold can last 2-3.
Poor casting? Might be?
Usually there shouldn't be a problem for a while.
But by all means remove them and flow test them.
If there is no rust in any of the exhaust passages.
Then you probably don't have an exhaust problem.

The worst thing you can do to a boat is let it set without starting.
Or let it set with the manifolds dry.
They rust faster when there is no water in the passages.

Get in there with a can of WD-40 and loosen all the electrical contacts and spray and re-tighten the connectors.
The battery cables/connections should be checked and greased yearly.
Remove the dist. cap and replace change the plug wires.
Just setting in a humid bilge can make em go bad.
 

SeaLord

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

Thank you all for suggestions.
Augoose, I had already visited that link and I posed the question on how to inspect the manifold, right because that article says there is no sure ways to come to a conclusion. I hoped experience may have contradicted literature.
Anyway that article seems to suggest that if you do not have sign of rust in the risers (elbows in my case) then manifold are safe since, if I understand correctly, elbows unite water and gas at a very high temperature facilitating rust. How does it sound to you ?
Same article says that when you hear engine knocking is too late.
You are suggestinh to flush engine after each usage. I do but sometimes I leave the boat in the water for a week 10 days. I have a flushing hose iin my engine I before the water pump. Is there any way I can flush it while in the water without the tap water hose (i.E. directly from a bucket of water ?)

Jerryjerry05 says "flow test them". Might you be a little more specific on how should i flow test them in a way I am sure there is no rust into inner of them?
i checked each and every cable to the spark and the voltmeter gives out sounding result. As mentioned earlier I have also had checked all cables and re tighten dielectric grease and all that. Engine started immediately. 4 days left in the water yet some trouble with starting. Basically I have been performing checking and rechecking for the last month: lot of sweat not real diagnosis.
thank you a lot
 
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jerryjerry05

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

Flow test.
Water should flow through the manifold as fast as it's put in.
Remove the manifold hook up a hose and see if it leaks into any cylinders.
 

Walt T

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Re: Chill over my back: What a white smoke from carb may ultimately mean ?

I'm a freshwater weenie and I replace mine every 10 years even if they look clean simply because the cost over 10 years is pretty cheap insurance. All it takes is a little bit of water and a very expensive motor can become junk real quick. I do like pulling off the risers every spring if only to replace the gasket which you don't want going bad either. That way I get a good look inside water passages and pull little fish out and feel kinda stupid because that seems to be the only way I can catch any stinkin fish. That brings me to a question that has always frustrated me... Why is it I sit in the same area, use the same bait or lures, same line as my fishing buddy, yet I can't even catch crabs from an aging hooker in Mexico and she catches stripers non freakin stop. I'm talking big ol Stripers outta Lake Powell and she fills coolers with them. She sits and chain smokes ciggies on the shore reading Fitty Shades Of Pink or some darn thing not even payin attention and the dang Stripers and occasional Walleye jump into the freakin coolers by themselves.
 
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