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BradD
08-28-2005, 04:57 PM
Wednesday my 1992 205 ran like a champ. Today, it won't idle. During warm up it felt and sounded like it was missing. As i would go to neutral to go into gear, it just died.
I manually held the throttle at the carb so that it wouldn'y go too low and die so i could shift into gear and run it.
Once in gear, it billowed white smoke out the back until at full throttle. At full throttle it ran fine. When i slowed back down it dropped well below the 650 Rpm's that it normally idles at and stalled.
I adjusted the idle so that it wouldn't stall, but it still was sputtering at 720 rpms.


I suspected that i had water in my gas and had dumped in some dry gas. After running for 20 - 25 minutes, no change.
Before i started investigating other causes, i wanted to run it by you all.
If I had a bad plug, would it run so well at full throttle?

Looking forward to your advice...
Brad

erkoehler
08-28-2005, 05:33 PM
It shouldn't run "perfect" at full throttle with a fouled plug. I would start by changing the plugs, get some fresh gas.

erkoehler
08-28-2005, 05:34 PM
Also, what was the temp during this time period???? You weren't over heating were you????? :confused:

BradD
08-28-2005, 05:39 PM
Temp looked good.
I'll throw in new plugs.
There's probably around 10 gallons in the tank now. I'll throw some fresh gas in.

erkoehler
08-28-2005, 05:41 PM
If there is any way to drain the tank, and get all fresh gas in there, that would be ideal!

Hopefully enginenut or JimN can provide some additional assistance if needed.

BradD
08-29-2005, 09:58 AM
How long does it take for dry gas to work it's way through.

Leroy
08-29-2005, 10:23 AM
Even with HEET, you still have the water in your tank, it is just mixed up now. So it could be until you run that tank out. I hope you don't have a head gasket problem. White smoke out both exhausts? Plugs will tell you alot also.

FlyingFreeman
08-29-2005, 11:02 AM
You might want to perform a compression check to see if you have a cylinder head gasket failure. You can get a gauge inexpensively from an auto parts store. Get one that has a metal fitting on the end of a hose that threads into the spark plug hole (some cheap ones have a rubber cork on the end that sort of threads into the plug hole-- don't get one of these).

1. Get a compression tester
2. Remove all spark plugs (disable ignition-- remove kill switch lanyard to prevent the coil from firing)

3. Open throttle fully- to allow air to flow freely into the cylinders
4. Record each cylinder's PSI while cranking
5. You are looking for similar pressures from each cylinder


A close inspection of the spark plugs can also give you some clues (even into a head gasket leak) but you have to look closely. You can go to your local library and look for an automotive repair manual that has pictures of the typical spark plug conditions that result from these types of failures. I believe that the spark plugs with water leaking into the cylinder are typically very clean (not lightly tinted brown from fuel).

If you had closed loop cooling, you would know if you had a cooling system leak (head gasket, intake manifold, etc.) by the loss of coolant.

It is possible that the intake manifold could be leaking coolant into the cylinder heads (coolant flows between the heads through the intake manifold). Check your engine oil for any clues that water is getting into it (milky oil, rusty dipstick, etc.).

The white smoke you see is likely steam. If water is leaking into the cylinders, you could damage your engine just by trying to start it. If water is in your cylinder and you crank the engine with the plugs installed, you could bend/break a connecting rod or crack a piston. Water will not compress.

I don't think that water in your fuel is causing the steam, but take a fuel sample (from the hose that's supplying your engine) and look for water in the bottom of your fuel sample if you think this could be your problem.

Don't be discouraged by the news. These boats are a dream to work on. Much better than any car!!

Good luck.

BradD
08-29-2005, 05:35 PM
Someone has suggested that maybe my choke is stuck? Does my 1992 have a choke?
I realize to some of you that may be one of the dumbest questions raised on this board, but I'm an idiot.

AirJunky
08-29-2005, 05:41 PM
Sounds like a fuel problem, not ignition. I'd look at the choke, accelerator pump or search for a vacuum leak, ie; at the carb base.

BradD
08-29-2005, 05:46 PM
So there's a choke? Could the choke be stuck? would WD40 help this?

AirJunky
08-29-2005, 05:50 PM
The choke is the butterflys that cover up the throat of the carb. Are they ever open? WD might fix it, but looking at it might reveal a tweeked linkage or missing piece.

BradD
08-29-2005, 05:51 PM
Thank you. I'll check tonight.

BradD
08-29-2005, 09:53 PM
Choke is fine.
Replaced plugs, what a pain in the **S. Still no change.
Next i'll replace the fuel filter. The question is why would my top end be fine if there was a problem with the fuel filter.

rektek
08-29-2005, 09:57 PM
pickup a length of fuel hose 3/8 I assume and run it from a gas can with fresh gas in it over to your fuel pump, bypass the tank in your boat.
see how it runs, running ok after, you know what you need to do, get that gas out of you boat tank, I have not had much luck with any of those water reducing products, water sits on the bottom of the tank, I have had luck siphoning the water of the bottom however.
you still might not be out of the woods though, carbs do not like water, corrosion and rust can form in a matter of days blocking idle passages and accel pump circuits.

post more info and one of us will figure it out .

redmike
08-29-2005, 10:04 PM
The question is why would my top end be fine if there was a problem with the fuel filter.
Exactly! sounds to me like you might want to do a compression check like flying freeman suggested. As for why a miss will show up more at low speeds than high speeds, the miss is still there, you just don't notice it as much. From the white smoke you described, I am afraid you have a bad head gasket. Had this happen to me, builder supplied gaskets both blew within 6 months! Hope I am wrong and it is something easier! Good luck to you!

Star92
08-29-2005, 10:17 PM
In my experience, carb problems such as stuck choke, will cause black smoke. Don't forget that you have 2 fuel filters on that boat, one fuel/water seperater/filter (looks like oil filter), and another in the bottom of your fuel pump. Skidim has both if needed. Alot of white smoke is not a good thing. A small amount of white smoke (steam) is very normal at take off, especially in cooler outside temps. If you've got alot of white smoke, good running condition at higher r.p.m.'s, Im guessing a intake gasket leak or head gasket leak. Like was said above, check your oil before you do anything else.

BradD
08-30-2005, 10:08 AM
Oil looks good.
My genious here at work is guessing some sort of gasket leak.
My next step was going to be the fuel filter. Is that a waste of time based on the gasket diagnosis?
Should I just yank the thing to the dealer?

rektek
08-30-2005, 04:17 PM
Black smoke = raw unburned fuel caused by cylinder misfire. stinks, burns your eyes when really bad.
White smoke/steam in light amounts is normal as all engines make H20, this type of smoke also has no odor
white smoke heavy= oil burning in combustion chamber, this also stinks and tends to billow and hang around.


pull all your spark plugs and keep them in order, plug inspection can give you clues as to which cylinder is not happy. hand turn the engine until each piston is at the top, look through the spark plug hole with a light- is one or more really clean ? bad head gasket/s will let water in combustion chamber and basically steam clean the cylinder, super clean top of piston BAD, run a compression test while you have the plugs out.

post more details, we're getting closer.

BradD
08-30-2005, 06:24 PM
Well gang, I just took my genious from work over to listen to the boat. It idled ruff, but no smoke. conistant power thru power up, but definely doesn't idle right. He suggested replacing the distributor cap and rotor, even the wires.
I'll keep in touch

BradD
08-30-2005, 06:55 PM
Here's something interesting from the MC manual. Under the troubleshooting area, "Engine misses or idles rough".
it suggests, "replace plugs", "tighten or replace high tension leads", "Replace pcv valve", "replace ignition coil", "See dealer".

What are the high tension leads?
What is the ignition coil?
Where is the pcv valve?

AirJunky
08-30-2005, 07:06 PM
What are the high tension leads? - ignition wires?
What is the ignition coil? - follow the center wire on the distributer to it.
Where is the pcv valve? - valve covers, usually has a hose on it going to the manifold or carb.

gregg
08-31-2005, 12:07 PM
Does not sound like an ignition issue to me. Most ignition problems will be worse under load or higher rpms. Look for a vacuum leak(lean condition), maybe a vacuum port that should have a hose on it or a port cap that has come off. Most too rich conditions will be black smoke due to unburnt hydrocarbons, but in extreme too rich conditions I have seen white vapor because of a cylinder being so loaded with fuel that none of it burns. Still sounds more like a lean condition from a vacuum leak, or one of the idle circuits being plugged in the carb. if it is carb fed and not throttle body. Other posibilities are carb. base gasket or intake manifold gasket.

BradD
08-31-2005, 02:17 PM
Well, I just spent my lunch hour replacing the Cap, Rotor, and Wires. Still not completely right, but should be able to use the boat this weekend.
Next step is to replace the fuel filter. THe dealer can't get me one until i take mine in. Apparently there are 3 posibilities for my boat and they want to confirm. Unfortunately, i can't see a part number on it.
I brought along a former GM engineer to assist me in my cap, rotor and wire replacement (I'm not very mechanical). He checked the PCV valve and felt it was functioning fine. Interesting...He disconnected the hose from the carb to the pcv valve and the rpm's went from 700 to 1200 and felt smooth, yet he feels the pcv valve is fine.
I'll keep you all posted.
THanks so much for your help.
Brad

gregg
08-31-2005, 02:34 PM
isurf: If rpm increased by removing a hose(creating a vacuum leak) could indicate idle is too rich. Were the spark plugs you took out black around the electrodes?? Does your engine have a mechanical fuel pump on the engine or an electric pump?? If mechanical, I have seen the diaphrams in the pumps rupture and leak fuel into the crankcase. Pull the dipstick see if it is overfull or smells like fuel. If so, your rich condition could be caused by the pcv pulling fuel vapors from the crankcase. Just another couple of possible causes.

Storm861triple
08-31-2005, 02:38 PM
isurf: If rpm increased by removing a hose(creating a vacuum leak) could indicate idle is too rich. Were the spark plugs you took out black around the electrodes?? Does your engine have a mechanical fuel pump on the engine or an electric pump?? If mechanical, I have seen the diaphrams in the pumps rupture and leak fuel into the crankcase. Pull the dipstick see if it is overfull or smells like fuel. If so, your rich condition could be caused by the pcv pulling fuel vapors from the crankcase. Just another couple of possible causes.

^What he just said. Now we're finally getting somewhere on this thread. You're too rich at idle. Where are you idle mixture screws set at?

BradD
08-31-2005, 05:52 PM
I think it's mechanical...it's a 1992 Ford 351.
The oil dipstick does show overfull!!! I thought that was weird.
So what do I do?

BradD
08-31-2005, 05:53 PM
I don't know how to answer where my idle screws are set.

Storm861triple
08-31-2005, 06:16 PM
I think it's mechanical...it's a 1992 Ford 351....
The oil dipstick does show overfull!!!...I don't know how to answer where my idle screws are set....So what do I do?

*Are you joking about the engine mechical? Mine is a '92 w/630 hours and it runs flawlessly.

*Smell the oil on the stick. If it smell like gasoline, change it.

*Turn the idle mixture screws in all the way, counting the turns until they gently bottom. Then you know where they are set right now. A good starting point for the idle screws is 1.5 turns out from bottomed, adn then from there you "feed the engine what it wants".

gregg
08-31-2005, 06:30 PM
I think it's mechanical...it's a 1992 Ford 351.
The oil dipstick does show overfull!!! I thought that was weird.
So what do I do?

Was it overfull the last time you checked it?? If not, it has to be water or fuel causing the level to raise (unless it produces its own oil ;) ). If it is water it should look milky, if it is fuel, should smell like it and be a little of the thin side. Pull a sample on the dipstick and stick a lighter under it. If it burns right away its a good bet there is fuel in the oil. Two ways for fuel to get into the oil, fuel pump diaphram ruture, or carb. problem(needle and seat, float ect)

G-man
08-31-2005, 06:33 PM
my 93 always read high, I would look at the color of the oil or send out an oil sample for analisis(sp)

BradD
08-31-2005, 07:04 PM
Storm, are you making fun of me? It's ok if you are, just making sure. The question was regarding my fuel pump being mechanical...
I don't know if the oi checked full before this problem, i just recently bought the boat and the previous owner had just recently changed the oil. I'll see if i can find out from him.

rektek
08-31-2005, 07:46 PM
sounds like your power valve is leaking inside your carb, replace the power valve and change the oil and filter, that's your problem.

remember idle screws are just fine adjustments, they cannot dump that much fuel as a leaking power valve can.

a good backfire through the carb can damage a power valve diaphragm, any backfires lately ?

Storm861triple
08-31-2005, 07:56 PM
Storm, are you making fun of me? It's ok if you are, just making sure. The question was regarding my fuel pump being mechanical...

LOL! I gotcha now! Sorry, and no I wasn't making fun at all. I thought you thought the engine's age was the root of the problem. Sorry about the confusion there.

Rektek just had a good suggestion about the power valve. That would definitely make it way rich at idle for sure.

BradD
08-31-2005, 09:40 PM
I'm just glad you caught my sarcasm.
The oil definitely smells like gas. The level is 3-4 inches above the "safe" mark on the dipstick.
The carb was replaced about 1 year ago. It's Holley, not sure of the model number.

BradD
09-01-2005, 09:00 AM
How many reasons can you think of for gas in the oil?

BradD
09-01-2005, 09:16 AM
The Holley is a 4160.

gregg
09-01-2005, 09:43 AM
How many reasons can you think of for gas in the oil?

Mechanical fuel pump, needle and seat or float. Enrichment or power valve will cause a rich idle for sure, but won't spill fuel into the crankcase.

BradD
09-01-2005, 10:03 AM
So it wouldn't be a waste of money to replace the fuel pump?

gregg
09-01-2005, 10:21 AM
So it wouldn't be a waste of money to replace the fuel pump?

Fuel pumps can be hard to diagnois because you can't see what is going on inside the pump. On the pump itself there should be a vent hole about the size of a pencil lead. Look around that area and see if you see any fuel dampness or stains. If it were mine, I would change the oil and filter, start it and see how it runs. Shut it off and look down the front and rear venturi and see if any fuel is dripping down to the throttle plates. If so, probably a float or needle and seat issue. Also after shutting it off, check that vent on the fuel pump body and see if it is damp with fuel.

Storm861triple
09-01-2005, 01:05 PM
The oil definitely smells like gas. The level is 3-4 inches above the "safe" mark on the dipstick.Wow. That's significant! DO the tests Gregg just mentioned above.

The fuel pump can be checked by removing it, and hooking an intake from the fuel pump to a bucket of fuel. Hand pumping the upm lever will show if fuel is leak out of the fuel pump on the crank case side of the pump.

-Tom

rektek
09-01-2005, 01:51 PM
a fuel pump leaking fuel internal into the crankcase can cause overfull on the dipstick, in bad cases the crankcase will actually overflow, this situation can be dangerous I've seen oil pans blown off after the fuel vapor ignited in the oil pan.

power valves, sticky needle and seat dumping too much fuel can find it's way into the crankcase, cylinders can only burn so much fuel, the unburned [raw] fuel can find it's way past the rings, this is not a good thing either. washing all the lubricant from the pistons [oil rings] causes premature wear and tear on cylinder walls and causes piston scoring.

happy wrenching

BradD
09-01-2005, 04:42 PM
Stupid question...no suprise. How many quarts of oil does a 351 Windsor take?

Storm861triple
09-01-2005, 05:00 PM
4 qts.

I think it's SUPPOSED to take 5, but in my '92, it's on the full line after filling the filter, w/only 4 qts.

-Tom

BradD
09-01-2005, 05:19 PM
Thank you.
I'm taking tomorrow off to try to get the boat running right.
Here's my plan.
Change the oil and filter.
Change the Fuel filter.
Replace the Fuel Pump...
This is in addition to the plugs, wires, rotor and cap already this week. This sucker will be all set to go next spring.
THe above gameplan is based on the input of this wonderful board. If any of you are in the Grand Rapids area and are mechanically inclined, let me know. I'd welcome any help.

West TN Wake
09-02-2005, 12:00 AM
We had similar problems with our boat. Have you thought about cleaning out the jets..maybe drilling them out if needed...you could try some sea foam. It is an addative that you can get at most any motor parts stores. It cleans and enhances some performace, although miminal it might clean you motor out and give you a little relif.
Wednesday my 1992 205 ran like a champ. Today, it won't idle. During warm up it felt and sounded like it was missing. As i would go to neutral to go into gear, it just died.
I manually held the throttle at the carb so that it wouldn'y go too low and die so i could shift into gear and run it.
Once in gear, it billowed white smoke out the back until at full throttle. At full throttle it ran fine. When i slowed back down it dropped well below the 650 Rpm's that it normally idles at and stalled.
I adjusted the idle so that it wouldn't stall, but it still was sputtering at 720 rpms.


I suspected that i had water in my gas and had dumped in some dry gas. After running for 20 - 25 minutes, no change.
Before i started investigating other causes, i wanted to run it by you all.
If I had a bad plug, would it run so well at full throttle?

Looking forward to your advice...
Brad

BradD
09-02-2005, 09:35 AM
Thanks, I had considered that. THe carb is 1 year old. I've had several people who are much more mechanically inclined that I on the boat and they feel that is not an issue.
If things don't run better after I do all the things i'm planning on today, I'll be open to anything.

BradD
09-02-2005, 06:42 PM
What an adventure.
When I last left you, I had replaced the plugs, wires, rotor and cap. Today changed the oil and oil filter, fuel filter and fuel pump. To some of you this may not sound like much, but to my family and friends, this is quite an accomplishment for me.
The bad news is after the expense of a new fuel pump, that didn't fix the problem.
The owner of the MC dealer told me the fuel pump wasn't required, but so many others insisted, i gave in.
Once I reported this to the dealer, he told me to bring it in. So at 2:05, I left the dealer. At 2:59 my son and I arrived back at the dealer with the boat. By 3:35 they came out to the waiting area and told me that my baby was fine.
The prognosis, a small obstruction in the shutoff for the secondary bowl. Gas kept being fed from the secondary at idle and low Rpm's. THis created a rich condition, hence the rough idle.
When I accelerated, the engine needed the extra gas from the secondary, so things ran well.
I hope my experience helps someone. I sure to appreciate all of you.

Storm861triple
09-06-2005, 12:17 AM
The bad news is after the expense of a new fuel pump, that didn't fix the problem.....The prognosis, a small obstruction in the shutoff for the secondary bowl. Gas kept being fed from the secondary at idle and low Rpm's. THis created a rich condition, hence the rough idle.
Which is why I said...
DO the tests Gregg just mentioned above.

The fuel pump can be checked by removing it, and hooking an intake from the fuel pump to a bucket of fuel. Hand pumping the upm lever will show if fuel is leak out of the fuel pump on the crank case side of the pump.
And Gregg said...
Shut it off and look down the front and rear venturi and see if any fuel is dripping down to the throttle plates. If so, probably a float or needle and seat issue.

I know you're not a great mecahinc, but anyone can break down the systems incrementally and TEST systems individually w/a little help from here, and then eliminate possibilities, leading to an accurate diagnosis. Sorry you spent money unnecessarily, but I told you clearly how to test the pump, and Gregg covered the issue you actually had, -the needle and seat- and I backed up his test advise... Oh well. :(

-Tom

BradD
09-06-2005, 09:38 AM
I've had to deal with more than one I told you so. I learned a valuable lesson.