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Twin 305's, recommissioning from two year lay-up.

K

kevc19

Member
So far I've pumped out some oil and didn't find any water, removed & cleaned spark plugs, sprayed into cyliders with light oil, removed valve covers, sprayed with light oil. Turned both engines by hand then cranked with starter before putting plugs/valve covers back in & cranking.

There now seems to be no fuel getting to the carburator or anywhere else that I can tell. I have two filters on each engine, the second an AC canister and it was dry on one side and about a fifth full on the other, haven't pulled the other filter (fuel/water seperator) yet but planning on replacing all and filling them up with gas. Not sure if there is a malfunction in the fuel pump though, how would I know? I have put a volt meter on the connections and there is power to the fuel pump. The fuel pump is an electric AC Declo.

Any suggestions would be appreciated.

Kevin
 
Many boat applications set up the electric pump to run ONLY after the oil pressure is up (for safety reasons). An oil pressure switch in the circuit ensures this, but you can jumper it out with a switch to prevent this obstinence. I did that with my old boat and the motor started right up (instead of cranking the hell out of it--not good for anything).

Jeff
 
If you have a hand pump oil extractor, remove the fuel line from the carb, attach a piece of hose to the fuel line and to the oil extractor. Pump away, let it suck fuel through the line until it is clear. Do it on both engines.

Some of the electric pumps will not prime themselves.

I would also manually fill the carbs through the bowl vent. I can almost guarantee that the floats are going to be stuck open from being dry. If you fill the carbs the floats will come loose in a little while. A little light tapping on the carb helps too.

If you choose not to do this step, there is a good chance the carbs will spill fuel over on the initial start.
 
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Thanks guys, Oil pressure is good from cranking by hand and with the starter while plugs were out, I will try the hand pump on the fuel line after resealing all filter gaskets with a light bead of oil. A friend told me today that he thinks my pump is toast, it is electric and has a diaphram, likely a rubber on that has been eaten away by ethanol after sitting for a couple years. I could put a couple of pumps on and convert it to a mechanical carter version to save future ethanol damage as I have read elsewhere; just one more thing for the list I guess and not too bad of a job from first glance.
 
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They should have mechanical pumps unless somebody converted to electrical.

Doing what Chris suggested in Post #3 will save you a whole lot of aggrevation.
 
I will try this first before converting to mechanical, the boat had several upgrades/conversions with the original owner so he may have put in the electrical pumps, though they look like factory installs with paint, etc. I'm pretty sure the carbs are Rochester Quadrajets and am unsure as to how to "fill the carbs through the bowl vent", do you mean to just pour gas in through the small butterflies or both butterflies? I have worked mostly on diesels in the Army so I'm comfortable with the work, just not experienced very much with gas.

Docksidemarineservices said:
If you have a hand pump oil extractor, remove the fuel line from the carb, attach a piece of hose to the fuel line and to the oil extractor. Pump away, let it suck fuel through the line until it is clear. Do it on both engines.

Some of the electric pumps will not prime themselves.

I would also manually fill the carbs through the bowl vent. I can almost guarantee that the floats are going to be stuck open from being dry. If you fill the carbs the floats will come loose in a little while. A little light tapping on the carb helps too.

If you choose not to do this step, there is a good chance the carbs will spill fuel over on the initial start.
Click to expand...
 
kevc19 said:
I will try this first before converting to mechanical, the boat had several upgrades/conversions with the original owner so he may have put in the electrical pumps, though they look like factory installs with paint, etc. I'm pretty sure the carbs are Rochester Quadrajets and am unsure as to how to "fill the carbs through the bowl vent", do you mean to just pour gas in through the small butterflies or both butterflies? I have worked mostly on diesels in the Army so I'm comfortable with the work, just not experienced very much with gas.
Click to expand...

Remove the spark arrestor. Look at the top of the carb, See attached picture.

photo.jpg
 
You can pretty much fill it until it comes out. No worries. Disconnect the throttle cable and while holding the choke open, actuate the throttle, Look down in the carb and see if the Accelerator pump is pumping. If it is you will see two streams of fuel squirt down the bore of the carb. It may take a few pumps to get the pump primed.


Stick with the gasoline for now. Carb cleaner will loosen everything up and you will have to definitely remove the carb to clean it. Quadrajets can function with a lot of debris in the bowl.


This step is important.

Re fill the carb and let it sit. You can tap on the carb with a small hammer at the fuel inlet to knock the float loose the next day before you try to start the engine. If the float is stuck open, gasoline will over fill the fuel bowl and come out the vent that I pointed out in the picture. No worries. Tap on the carb a little more, this works most of the time. In a worst case you will have to remove the carbs for a good cleaning.

Let us know how it goes....
 
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Thanks again Chris, I will definitely let you know how it goes and really appreciate the detail of your posts. I'm heading down on Sunday early and hope to go from here to there in the day, so I'll probably let them sit a few hours before tapping with the hammer like you suggested.

Thanks again!

Kevin

Docksidemarineservices said:
You can pretty much fill it until it comes out. No worries. Disconnect the throttle cable and while holding the choke open, actuate the throttle, Look down in the carb and see if the Accelerator pump is pumping. If it is you will see two streams of fuel squirt down the bore of the carb. It may take a few pumps to get the pump primed.


Stick with the gasoline for now. Carb cleaner will loosen everything up and you will have to definitely remove the carb to clean it. Quadrajets can function with a lot of debris in the bowl.


This step is important.

Re fill the carb and let it sit. You can tap on the carb with a small hammer at the fuel inlet to knock the float loose the next day before you try to start the engine. If the float is stuck open, gasoline will over fill the fuel bowl and come out the vent that I pointed out in the picture. No worries. Tap on the carb a little more, this works most of the time. In a worst case you will have to remove the carbs for a good cleaning.

Let us know how it goes....
Click to expand...
 
fastjeff said:
Many boat applications set up the electric pump to run ONLY after the oil pressure is up (for safety reasons). An oil pressure switch in the circuit ensures this, but you can jumper it out with a switch to prevent this obstinence.
Click to expand...
Jeff's idea is great, and many install a switch like this at the helm. It eleminates the need for the "start by-pass" during cranking.
Activate the switch and the fuel priming begins ...... and no unnecessary engine starter motor wear, no battery bank drain....... excellent idea.

However, note that any fuel pump system shut-down over-ride switch must be "momentary".......... meaning that must return to N/O.
There must be no means of this switch being left "ON".

fastjeff said:
Most marine techs agree that mechanical fuel pumps are very reliable--not infallible, but reliable.
Jeff
Click to expand...
Agree! They tend to last for a very long time.



If you do not already own one, you can't beat the Tempo Oil Boy extractor.
Also works great for fuel priming, priming a closed cooling system WH or Cabin Heater, evacuating coolant, etc.

Tempo.OilBoy..jpg


As for priming your fuel bowls..... a chemical squeeze bottle is what I use.
Make a small hole in the cap so that expansion does not cause any unwanted liquid to squirt out when not being used.
When being used, I hold one finger over the vent hole and squeeze. Near perfect aim each time.
images
 
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I would use a spring loaded switch so there would be no way to leave it on. Might even put a cover over it to prevent accidents. Belt and suspenders don't you know.
 
missnancy said:
I would use a spring loaded switch so there would be no way to leave it on. Might even put a cover over it to prevent accidents. Belt and suspenders don't you know.
Click to expand...

Just hook a fused wire from the "I" terminal on the starter solenoid to the power input of the fuel pump. It will supply power to the pump while cranking the engine and once you release the key and the solenoid goes open, so does the "I" terminal.

Once oil pressure builds the OP switch will take over.
 
I doubt if that's legal, and here's why: If the motor died from a ruptured fuel line, you wouldn't know that as you're cranking her over with the electric pump shooting gas into the bilge!

Jeff
 
Okay, so I've filled the carbs through the vents....and then some. I used a battery operated transfer pump and should have been more careful with it because it filled up my little funnel and then some running down into the barrels. I've used a hand pump to pull out what I was able to see but it sounded like a lot of draining going on once I stopped the pump and the funnel emptied. Same thing on the other engine except less spillage, hand pumped the barrels again and heard the draining noise (gurgle, gurgle). Also used a hand pump on the fuel line after removing it from the carb housing, still waiting on the other side as it is stuck and I sprayed it with some Deep Creep.\

Any precautions given the extreme fill up situation? Top of the block looks pretty shiny though...I'll work on some other stuff before moving forward with anything else on the fuel system.

Thanks,

Kev

Docksidemarineservices said:
You can pretty much fill it until it comes out. No worries. Disconnect the throttle cable and while holding the choke open, actuate the throttle, Look down in the carb and see if the Accelerator pump is pumping. If it is you will see two streams of fuel squirt down the bore of the carb. It may take a few pumps to get the pump primed.


Stick with the gasoline for now. Carb cleaner will loosen everything up and you will have to definitely remove the carb to clean it. Quadrajets can function with a lot of debris in the bowl.


This step is important.

Re fill the carb and let it sit. You can tap on the carb with a small hammer at the fuel inlet to knock the float loose the next day before you try to start the engine. If the float is stuck open, gasoline will over fill the fuel bowl and come out the vent that I pointed out in the picture. No worries. Tap on the carb a little more, this works most of the time. In a worst case you will have to remove the carbs for a good cleaning.

Let us know how it goes....
Click to expand...
 
And if I didn't have my hands full enough....the fuel line near the carb got twisted when removing the nut, the pic attached shows it's twisted back but definitely has been pinched. I finally got the nut off but now what??

fuel line_sb_4-1-12.jpg

Thanks,

Kev


kevc19 said:
Okay, so I've filled the carbs through the vents....and then some. I used a battery operated transfer pump and should have been more careful with it because it filled up my little funnel and then some running down into the barrels. I've used a hand pump to pull out what I was able to see but it sounded like a lot of draining going on once I stopped the pump and the funnel emptied. Same thing on the other engine except less spillage, hand pumped the barrels again and heard the draining noise (gurgle, gurgle). Also used a hand pump on the fuel line after removing it from the carb housing, still waiting on the other side as it is stuck and I sprayed it with some Deep Creep.\

Any precautions given the extreme fill up situation? Top of the block looks pretty shiny though...I'll work on some other stuff before moving forward with anything else on the fuel system.

Thanks,

Kev
Click to expand...
 
Just ran the port side for about five minutes, took a few times and a little gas at the go but she settled down to a nice idle. She sucked a good bit of water in the beginnning then it seemed to die off, I check the temp guages at both helm stations and they weren't reading anything.


kevc19 said:
And if I didn't have my hands full enough....the fuel line near the carb got twisted when removing the nut, the pic attached shows it's twisted back but definitely has been pinched. I finally got the nut off but now what??

View attachment 4215

Thanks,

Kev
Click to expand...
 
You will need to replace the fuel line. You can get a flexible replacement line. Next time, remove the small nipple from the carb and hold the strainer fitting with a 1" wrench to avoid twisting the line.
 
Got it, Thanks. I am guessing that to replace the entire length will be about 3'. This is on the starboard side and now it's giving me fits, lot's of knocking, especially right after turning over, seems like it takes some time but settles down and goes away all together afterwhile. At first it was jumping at the transmission shaft and outside at the prop so I thoughtit was just jumping due to a lack of lubrication at the stuffing box because I could feel it through the floor of the boat and had someone looking at it. I did turn this shaft last weekend and heard the prop turn as well; related???

Also just noticed that the choke on this one is stuck open, take a look at the pic below, it's the total opposite on the port side.

choke_sb_4-1-12.jpg


Docksidemarineservices said:
You will need to replace the fuel line. You can get a flexible replacement line. Next time, remove the small nipple from the carb and hold the strainer fitting with a 1" wrench to avoid twisting the line.
Click to expand...
 
I suppose the knocking could be the two year old fuel but I'd like to figure it out before going into the water in a few weeks. May 1 actually is my goal so we'll see.

My other goals before launch are to put in gor tex gfo fiber shaft packing and a new holding tank among the normal bottom paint, wash, wax etc. Any other advice before launch?

kevc19 said:
Got it, Thanks. I am guessing that to replace the entire length will be about 3'. This is on the starboard side and now it's giving me fits, lot's of knocking, especially right after turning over, seems like it takes some time but settles down and goes away all together afterwhile. At first it was jumping at the transmission shaft and outside at the prop so I thoughtit was just jumping due to a lack of lubrication at the stuffing box because I could feel it through the floor of the boat and had someone looking at it. I did turn this shaft last weekend and heard the prop turn as well; related???

Also just noticed that the choke on this one is stuck open, take a look at the pic below, it's the total opposite on the port side.

View attachment 4216
Click to expand...
 
If this is an inboard and the engine has a miss the transmission will make a banging noise. Some mistake this noise for an engine knock.

Sounds like a full T/U is in order.
 
Summary of Today's Progress:

Port engine - after following Chris' instructions to refil the bowl on the carb and priming the fuel pump & lines with a hand pump, the engine fired with the help of a few shots of starter fluid. Ran it up to about 120 degress F and got the RPM's up to around 1600-1800. The only issues that I noticed was a short hiss. I checked & tightened the spark plugs on one side where it sounded like it might be coming from and reinstalled the flame arrestor that I had removed and started it back up, the short hiss sounded like it was still there but greatly muffled. Anything to be concerned about?

Starboard engine - again after following Chris' instructions to refil the bowl on the carb and priming the fuel pump & lines with a hand pump, the engine fired with the help of a few shots of starter fluid. Ran it up to about 135 degress F and got the RPM's up to around 1600-1800. Immediated I noticed a knocking noise and turned off the engine and went to get a friend at the marina to watch the props; started it back up, the knocking sounded like it was coming from the transmission and sure enough the shaft at the transmission was jumping/quickly turning about a quarter of an inch and then abruptly stopping. I ran the engine for quite awhile and it seemed to also be coming from inside the engine but I couldn't tell from where, front or back it trailed off and stopped altogether for quite awhile and then I shut it down. Turned it back over a minute later and the knocking was back. That's where I left it.

kevc19 said:
I suppose the knocking could be the two year old fuel but I'd like to figure it out before going into the water in a few weeks. May 1 actually is my goal so we'll see.

My other goals before launch are to put in gor tex gfo fiber shaft packing and a new holding tank among the normal bottom paint, wash, wax etc. Any other advice before launch?
Click to expand...
 
Make sure the filters are clean, change the oil, oil filters and top off all fluids. Make sure the raw water pumps are functioning correctly, in fact replace the impellers.

Put it in the water and run it. For a while.
 
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