350 issues

[glashole]

I have a pair of 1998 350's (260 hp) in my cruiser with bravo 3

the one seems to be having a couple issues, but not the other one

this started last year and i was sure it was a fuel tank issue and it is continuing this year
I ran the tank almost empty last year and it started on the last ride
i thought it was **** in the tank
I then filled it up for the winter storage and I changed the fuel filter before launching
I may have not put enough stabilizer in it for the year (not sure)
each motor runs off its own tank

the motor runs very well, idles perfectly, and gets out of the hole just fine

when crusing about 3100- 3500 it will periodically cut out and drop rpms drasically but not completely and it spits and sputters, it will go away if i increase rpms
when i ran the boat about 3800 it was fine
it will also run wfo fine as well
but the lower rpms it cuts out than comes back and cuts out again

not sure if it is the angle the boat is at these rpms but I screwed with the tabs and it didn't seem to do anything

I have run 1/4 a tank through it and filled it up and ran 1/2 a tank through it and filled it up and it has continued

i was planning on changing out the plugs, filling it up again and changing the fuel filters again

does this sound like a fuel issue or could it be electrical, should i put more additive in the tank?

all of the gauges stay the same when it happens except of course the rpm

[gcarter]

Maybe a quick check could be done by building a simple fuel manifold so you could run both engines from the one tank where you're getting good results.
Something simple like copper tubing.

[BUIZILLA]

Q-jet?

[glashole]

I am not sure

[BUIZILLA]

Hat removal for identification is an indoors courtesy....

[glashole]

sorry chum

thought the thunderbolt thing would say what it was

will get the appropriate pictures this afternoon

Shea

[zelatore]

I haven't studied a Holly in a while, but that fuel line attachment doesn't look right (?).

Regardless, if it is fuel I'd have to guess primaries only.

[handfulz28]

'97-98 = Weber?

[The Hedgehog]

'97-98 = Weber?

Don't they have the bowls on the sides?

[handfulz28]

No clue...just did a quick parts lookup for year/model. Gotta figure the Qjet was NLA by that time and the only other thing that shows up is a 2-barrel Mercarb, which kinda looks like a Qjet?

I'm gonna guess ignition related. Coil or module, which should be easy to swap and help diagnose.

[mrfixxall]

its one of those ole 2v carbs,,get some carb cleaner and hose it down in side the carb..Rev it to 4k rpm and slam the choke shut (if its not one of those newer style 2v that dont have a choke) or cup your hand and place it over the top of the carb whyle reving the engine almost stalling it then pull your hand away and let it rev up again..this will suck any crap out of the little holes inside the carb..

If its still acting up then look into a tune up and or the coil or pick up coil...ive replaced alot of pick up coils this year with similar symptoms..

[motorcity]

I think th carb is a Carter, they use the same one on the 4.3L. I wonder if it could be the Distributor module, beacuse it is RPM related. If it was fuel it would be at other RPM's.

[glashole]

does this help

[gold-n-rod]

Certainly NOT a Quadrajet.

[MOP]

You can try switching fuel source like mentioned above may work, my thinking is it is a little krap in a passage. Try what Mike said run it up and choke it out a few times to see if you can suck it through!

[roadtrip se]

Try replacing the water separator element, again.

May be a simple fix.

[BUIZILLA]

swap them between engines.... easy and cheapest thing to do

[VetteLT193]

I can't remember if Formula builds in a backup tank/tank valve with lines... can you follow the fuel lines to check?

I'm thinking they have one built in,but that could have been a different boat I'm thinking of.

***edit, I'm thinking of another member with a Formula, what kind of boat?***

[mrfixxall]

theirs another filter in that carb! get a 5/8 line wrench and a 1'' wrench and remove the fuel line. now that the fuel line is removed take the 1'' wrench and remove the fitting that holds the mini fuel filter but be careful because the filter and spring in that little hole will fall out,you may have to use both wrenches to remove the main fuel line,somtomes when you try yo remove the fuel line it will brake loose the fitting thats on the carb and you dont want to kink the fuel line..when installing the new filter be careful because its real easy to cross thread the fitting into the carb..make sure you hand tighten it then a snug it with the wrench..


BTW if your going to use the choke method to suck the crap out of the carb loosen the 7/16 nuts on the throttle linkage and operate the throttle by hand :)

[glashole]

what order should this all take place

clean carb then change filter?

is this a special filter or can i get it anywhere

looking to this tonight after work and would like to have all the stuff there when i do it

did we get a concensus on the type of carb

[VetteLT193]

I think it's the Mercarb. Merc's version of the rochester.

[mrfixxall]

what order should this all take place

clean carb then change filter?

is this a special filter or can i get it anywhere

looking to this tonight after work and would like to have all the stuff there when i do it

did we get a concensus on the type of carb


its a rodchester 2v carb, you may have to remove the filter first to see which type it is,it's probably a brass style that you can clean with carb spray.or get your serial # off the plastic carb cover and call your local arina and get 2 new firlters for both engines..

warm both engines up, shut it off and remove the carberator throttle cables from the carbs,start engine and use the throttle by hand,raise the rpm and start hoseing the inside of the carb down whyle trying to maintain a constant engine speed around 2k,,after you went through a 1/2 of the can of carb spray rev the emgine to 3500-4000 rpm.whyle reving the engine snap the choke shut and open the throttle blade all the way.this will suck the chit out of the carb circuits..try to keep the engine running at all times..

call me!630-688-7014 or ill be trying all day:)

[glashole]

I pulled the small filters on the carb and they were in real good shape

good call on the "be careful with the spring inside" that bad boy would have been gone had i not been paying attention

I then cleaned the carb in the manner described above on both motors which was a real easy thing to do

not having a new main fuel filter to install I left that alone and will change it out tonight

anyways i took it for a rip and it was doing exactly the same thing
so tonights job is to change the filter again, try to get a diagnostic machine to hook up to it and run it for a while

its at 1/2 tank fuel right now so i was going to run it down to fill it up for the weekend

hopefully the new filter will help and if not i hope the scanner will come up with something

now if i keep filling it up and there is water in the fuel tank will the water eventually go away or should I be adding some sort of additive?

[VetteLT193]

The water should settle down to the bottom of the tank and be the first thing sucked out. Do you have racor filters? you can drain off the water at the bottom of them.

If you don't, you can add Star Tron to the tanks. It won't hurt to add it regardless of you fuel filter type.

[glashole]

I am running the std merc filters

never heard of star tron
would it be the same as gas-line antifreeze
(methol hydrate for you southerners)

[VetteLT193]

here is star tron... http://mystarbrite.com/startron/

It's a new-ish product... kind of an all in one fuel additive for dummies. You can't put too much in, it handles Ethanol, water, and other problems. I like it because it's just simple to use. It's not the cheapest stuff out there though.

Another thought I have for your problem...

If the Ignition is getting a bad signal from a sensor, or there is something screwy going on with the ignition or a related component, it could be messing up the advance... which in turn could cause your issue.

[glashole]

changed th fuel filter again and it is still happening

the marina seems to think electrical and they are doing a compression test on the motor to check that out as it seems to be losing 1 cylinder when it starts screwing up

we'll see

i would assume based on my experiences that it will be whatever ends up costing the most amount of money :)

[BUIZILLA]

the marina seems to think electrical and they are doing a compression test on the motor to check that out as it seems to be losing 1 cylinder when it starts screwing up

what does electrics have to do with compression ? :confused:

[Trueser]

We had a similar issue at AOTH that ended up being the alternator.

[glashole]

sounds like it is losing a cylinder

if its not electrical then it is a pooched cylinder

[BUIZILLA]

the motor runs very well, idles perfectly, and gets out of the hole just fine



if its not electrical then it is a pooched cylinder read this twice...

[glashole]

the motor is the black thing in the back of the boat right :confused:


:) guess i am just assuming the worst after they said they were doing a compression test etc

should have an answer tommorrow hopefully

suppose to go to alexandria bay NY in the 1000 isles for their biker's weekend tommorrow night with a group of other boats so i am really hoping this gets resolved

[handfulz28]

I'm gonna guess ignition related. Coil or module, which should be easy to swap and help diagnose.

????

[VetteLT193]

pooched cylinders wouldn't run better at a higher rpm.

Read handful's post again, and I still say it's a sensor because of the TB V automatic stuff.

[CHACHI]

the motor is the black thing in the back of the boat right :confused:


:) guess i am just assuming the worst after they said they were doing a compression test etc

should have an answer tommorrow hopefully

suppose to go to alexandria bay NY in the 1000 isles for their biker's weekend tommorrow night with a group of other boats so i am really hoping this gets resolved
Shea, I am heading to A-Bay for a wedding, I will try to swing by the docks and see if you are there.

Ken

[glashole]

i am trying to get an answer right now as to why this would all be happening becuase none of it makes sense
but apparently there is minimal compression in 2 cylinders



Ken- we are staying at the riversedge so I imagine i would be crashing the wedding you are going to anyways.. :)

we have a bunch of slips booked and are trying to be on the easternmost wall so come look for us , i am assuming we will be easy to spot

i will be on a green 28 searay now with the boat issues here

looking forward to seeing you
(i will be the drunk one bitching about his boat :bonk:)

Shea

[CHACHI]

Shea, I will come lookin for ya.

I will be the guy in a suit bitchin about wearing a tie.

Ken

[glashole]

Update

pulled the heads and had a couple of bad valves
both heads being removed now to be redone and should be good to go shortly

will let you know if there is anything different