1986 225E engine dies in idle

Rivergator

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I actually have 2 problems. When the engine is running a tiny amount of oil leaks through the center bolts on both sides of the intake manifold. I tightened up the bolts slightly and the leak stopped on one side but still trickles up on the other side. I don't see any water in the oil. What is the meaning of this? Is there a small leak at the gasket under my intake manifold or is it just where the bolts are? The other problem is a little bigger. I haven't had the boat in the water all summer because of some serious repairs that needed to be done to my steering. This is all done now and I am getting ready to launch the boat. I am test running my engine and the engine runs just fine as long as I keep it above 1000 rpm but it stalls, it dies when throttling back to idle. Last year it was idling just fine. What has gone wrong? Could it be the old gas, even though I treated it at the end of last years season, a possible vacuum leak, or is it a carb problem?
 

Bondo

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Re: 1986 225E engine dies in idle

I actually have 2 problems. When the engine is running a tiny amount of oil leaks through the center bolts on both sides of the intake manifold. I tightened up the bolts slightly and the leak stopped on one side but still trickles up on the other side. I don't see any water in the oil. What is the meaning of this? Is there a small leak at the gasket under my intake manifold or is it just where the bolts are? The other problem is a little bigger. I haven't had the boat in the water all summer because of some serious repairs that needed to be done to my steering. This is all done now and I am getting ready to launch the boat. I am test running my engine and the engine runs just fine as long as I keep it above 1000 rpm but it stalls, it dies when throttling back to idle. Last year it was idling just fine. What has gone wrong? Could it be the old gas, even though I treated it at the end of last years season, a possible vacuum leak, or is it a carb problem?

Ayuh,.... Welcome Aboard,.... For the intake leak, pull each bolt, 1 at a time, 'n seal the threads with perfect seal or permatex 3,....

Then reinstall at 'bout 35ft.lbs...

For the stallin' at idle, I'd guess bad gas, or crud blockin' the carbs idle circuit,...

Start with checkin' the Contents of the filter for anything but fresh smellin' gasoline,...
 

Rivergator

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Re: 1986 225E engine dies in idle

Ayuh,.... Welcome Aboard,.... For the intake leak, pull each bolt, 1 at a time, 'n seal the threads with perfect seal or permatex 3,....

Then reinstall at 'bout 35ft.lbs...

For the stallin' at idle, I'd guess bad gas, or crud blockin' the carbs idle circuit,...

Start with checkin' the Contents of the filter for anything but fresh smellin' gasoline,...

Thanks Bondo, I will start on the bolts and reseal them. The little gas filter inside the carb inlet is like brand new clean and the main gas filter is brand new. If you think it is a gas issue, how about this. I will add 10 gallons of fresh gas to the tank of which 5 gallons is ethanol free marine fuel and 5 gallons regular. This will raise the octane from 87 to about 89 because marine fuel is 91 octane and lower the ethanol content from 10 to 5%. There is very little old fuel from last year left in the tank. Then I will have two 5 gallon spare tanks of totally fresh gas on the aft deck, take the boat out and run it dry to get all the old stuff out and then refuel with fresh clean new regular fuel from the spare tanks and see what happens. Also is there an additive that I can mix into the old gas that will remove crud or anything else that is bad from the idle circuit. Btw, what is an idle circuit? Are you referring to some jets inside the carb or is it something that I can look at and clean without ripping the carb open.
 

Bondo

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Re: 1986 225E engine dies in idle

Thanks Bondo, I will start on the bolts and reseal them. The little gas filter inside the carb inlet is like brand new clean and the main gas filter is brand new. If you think it is a gas issue, how about this. I will add 10 gallons of fresh gas to the tank of which 5 gallons is ethanol free marine fuel and 5 gallons regular. This will raise the octane from 87 to about 89 because marine fuel is 91 octane and lower the ethanol content from 10 to 5%. There is very little old fuel from last year left in the tank. Then I will have two 5 gallon spare tanks of totally fresh gas on the aft deck, take the boat out and run it dry to get all the old stuff out and then refuel with fresh clean new regular fuel from the spare tanks and see what happens. Also is there an additive that I can mix into the old gas that will remove crud or anything else that is bad from the idle circuit. Btw, what is an idle circuit? Are you referring to some jets inside the carb or is it something that I can look at and clean without ripping the carb open.

Ayuh,.... Bad gas is just Bad,... No fixin' it,....
That's why I asked 'bout the Contents of the old filter,...

To Test yer situation, plumb a remote tank, with clean fresh gas to the fuel pump, or remote filter, 'n Run it,...

If it runs Better, ya found the Problem,...
If it don't, look elsewhere,...

Carbs have several circuits built into 'em, idle, mid-range, 'n Wot,...
'n of course, the accelerator pump, 'n choke,...
 

jerryjerry05

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Re: 1986 225E engine dies in idle

IF??? There is any water in the tank, then you need to clean it out?
An 1986 anything that's set any time can have a lot going on in there.
The motor came stock with 2 filters.One in the carb itself, the second down by the fuel pump.
They usually rusted up so bad lots of them have been removed.
The line to the carb,Is it still a solid metal line or been changed to rubber?
Anyway take it loose, unhook the coil lead and try to pump same gas through into a clear container.
See if there is any water or crud.
The inline filter?? see if there is any water or gunk in it?
If the water sep filter is new see if anything has worked it's way to it?
Adding good gas on top of old gas isin't a good idea.
If you think there is ANY crud in the tank get it cleaned or clean it yourself.
There is a fuel tank sending unit that is usually in an accesable area.
Remove it and you can look inside and see what's in there.
Watch for spark if it's gonna be open and cleaned.
No air tools,or electric drills or vacuum cleaners.
Bad gas can and will explode.Lost a mechanic because of a portable electric drill.
 

Walt T

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Re: 1986 225E engine dies in idle

Has the carb ever been gone through or is it original 1986 vintage? If it is don't fool around with it, the idle circuits are blocked as mentioned and the little tiny green men in there are waiting until winter to block up something else. At least that's what I tell people who come in in the spring and say "It ran fine when I put it away" Or maybe say muffler bearing or something. No seriously it most likely needs to be gone through by an expert or an old guy who worked on Model Ts and toured with Elvis. Good advice being given, check tank, pump, filter, muffler bearing etc. Be a good time to quit smoking unlike the old guy who's been smoking for sixty years and it aint killed him yet.
 

Rivergator

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Re: 1986 225E engine dies in idle

Has the carb ever been gone through or is it original 1986 vintage? If it is don't fool around with it, the idle circuits are blocked as mentioned and the little tiny green men in there are waiting until winter to block up something else. At least that's what I tell people who come in in the spring and say "It ran fine when I put it away" Or maybe say muffler bearing or something. No seriously it most likely needs to be gone through by an expert or an old guy who worked on Model Ts and toured with Elvis. Good advice being given, check tank, pump, filter, muffler bearing etc. Be a good time to quit smoking unlike the old guy who's been smoking for sixty years and it aint killed him yet.

No, the carb has never been gone through. Everything on the boat is in excellent shape and original. Despite its age the boat does not have enough hours on it to warrant any kind of overhaul. However, my concern is, with the event of E10 may it have done harm to the fuel system. In 1986 engineers did not anticipate this E10 crap and the materials used inside the fuel system may not be able to withstand the harshness of E10. Up to 2 years ago I was able to get E5 gas and I did not have any problems. This may be the only reason a carb overhaul may be necessary, not because of mileage. But here is what I did. I pumped all the old gas out of the tank by attaching a little auxiliary tank directly to the carb inlet filled with fresh 100% non-ethanol marine fuel. I checked the timing and the dwell and both are within specs and yet the new, clean gas did not make a difference. The engine still dies in idle. I understand, if there was an intake manifold leak of some sort, that the rpm would actually go up and not down, is that true? So it may be that the carb is the culprit after all. Is there a good carburator cleaner or solvent that I can feed into the carb, flood the whole thing with it internally, let it sit for a couple of days and all will be well, or am I dreaming?
 

Bondo

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Re: 1986 225E engine dies in idle

No, the carb has never been gone through. Everything on the boat is in excellent shape and original. Despite its age the boat does not have enough hours on it to warrant any kind of overhaul. However, my concern is, with the event of E10 may it have done harm to the fuel system. In 1986 engineers did not anticipate this E10 crap and the materials used inside the fuel system may not be able to withstand the harshness of E10. Up to 2 years ago I was able to get E5 gas and I did not have any problems. This may be the only reason a carb overhaul may be necessary, not because of mileage. But here is what I did. I pumped all the old gas out of the tank by attaching a little auxiliary tank directly to the carb inlet filled with fresh 100% non-ethanol marine fuel. I checked the timing and the dwell and both are within specs and yet the new, clean gas did not make a difference. The engine still dies in idle. I understand, if there was an intake manifold leak of some sort, that the rpm would actually go up and not down, is that true? So it may be that the carb is the culprit after all. Is there a good carburator cleaner or solvent that I can feed into the carb, flood the whole thing with it internally, let it sit for a couple of days and all will be well, or am I dreaming?

Ayuh,.... It sure sounds like yer dreamin',.... Runnin' carb cleaner through the carb, Ain't a carb Rebuild,...
 

Scott Danforth

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Re: 1986 225E engine dies in idle

VP used a lot of holley carbs in the mid 80's. I can tall you from experience that running carb cleaner thru will NOT clean out anything. I must have rebuilt 50-75 Holley carbs in my life time so far. Get a proper rebuild kit, a good carb cleaner to soak parts in, and some small bits of copper wire to poke thru passages to clean out the gunk.

In some cases the crud can be like concrete

Most likely both the idle circuit and the power valve circuits are plugged
 

jerryjerry05

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Re: 1986 225E engine dies in idle

Most additives do nothing.The drygas additives don't really dry your gas either.
The only additive I've ever thought was good is the Product from Chevron.It has Techron and it comes in a black bottle with a long spout.
Had a Ford PU and it ran ok.I ran it almost out of gas and put in 1 bottle of the techron and 1 gal of gas.
I drove around the block.I could actually feel/hear the difference in the way the motor ran.
It smoothed out and ran much better.Considering it ran good before? The difference was amazing.
Since then I've done this on all my vehicles.
The carb is 27 might be time for rebuild.
(Despite its age the boat does not have enough hours on it to warrant any kind of overhaul)Just normal use and time will gum up a carb.
Most boats set WAY more than being used.
The carb/fuel dries out from setting and the gunk builds up in the bottom.
 

Walt T

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Re: 1986 225E engine dies in idle

Yep, sitting for long periods of time does not help engines and carburetors. They are designed to be used, not to sit.
 
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