HELP mercury bridgeport problem

[pugo]

Hope somebody on here can reslove what is now becoming a pain in the preverbial

recently i purchased a ring 18 with a v6 bridgeport engine on it , the outfit has been sitting around for 5 years untouched, i serviced it, stripped and rebuilt the impellor, changed lower unit oil, changed all the fuel and lines , stripped and rebuilt carbs the engine fires up and purrs like a ***** cat, blip the throttle and she is very very responsive, put her in the water and out of gear she ticks over lovely and revs clear, engage drive and she wont rev over 1200 to 1500 rpm you just have to touch the throttle a ad more and she bogs and dies, but fires straight back up, i pottered around in her for about 15 mins at just over idle and she runs on all 6, dont get hot....she just wont acceleate???????she actually felt like i had something round the prop holding her back

any ideas where to look next ????

please

Pugo

 

[pugo]

Re: HELP mercury bridgeport problem

just to update,

i checked the stator for resistance and

red to ground is 74
blue to red is 4.39
blue to ground 4470

is this shot?

 

[Faztbullet]

Re: HELP mercury bridgeport problem

The serial # or year posted would help as there are different ignitions and set-up for different years.

 

[Dukedog]

Re: HELP mercury bridgeport problem

Check
Red to blue
Red/white to blue/white
Red to black
Red/ white to black................

Post all readings.

 

[pugo]

Re: HELP mercury bridgeport problem

its circa 1982 i think, no serial number anywhere i can find, its a 200hp v6 i have been told,

i shall test stator again when i get in tonight

pugo

 

[pugo]

Re: HELP mercury bridgeport problem

Check
Red to blue
Red/white to blue/white
Red to black
Red/ white to black................

Post all readings.

Red to Blue 4.15(meter at 20k)
Red/w to Blue/w 4.12(meter at 20k)
Red to black 70 (meter at 2k)
Red/w to black 70 (meter at 2k)
Blue to black 4.19(meter at 20k)
Blue/w to black 4.22(meter at 20k)
Blue to Blue/w 8.41 (meter at 2k)

is that all ok ?

 

[Dukedog]

Re: HELP mercury bridgeport problem

Red to Blue 4.15(meter at 20k)
Red/w to Blue/w 4.12(meter at 20k)
Red to black 70 (meter at 2k)
Red/w to black 70 (meter at 2k)
Blue to black 4.19(meter at 20k)
Blue/w to black 4.22(meter at 20k)
Blue to Blue/w 8.41 (meter at 2k)

is that all ok ?

Blue to black 4.19(meter at 20k)
Blue/w to black 4.22(meter at 20k)
Blue to Blue/w 8.41 (meter at 2k)

These arn't necessary. I'm away from my stuff right now but tha red ta black and red/white ta black don't look right.

Does tha stator have a number on it? Something like 5454 A (number)

 

[pugo]

Re: HELP mercury bridgeport problem

i cant give the serial of the stator yet as i need a flywheel puller and am waiting for it to arrive from the states....!

however as soon as i get it off i shall post up the serial

so you think 70 is too low ? and if the stator was down would you expect it to not rev over circa 1500 rpm under load ?????

Pugo

 

[Dukedog]

Re: HELP mercury bridgeport problem

Tha stator readings may be good but tha only way ta be sure is with a DVA and motor running. Even a bad high side will rev ta around 3 grand under a load.

Just a few more things ta check,
Compression?
Timing? Should have a rev limiter unless its been removed. If it hasn't, trash it.
Trigger ohm?
Fuel pump? Pressure?
Floats set at right height?..............

 

[pugo]

Re: HELP mercury bridgeport problem

i shall check all this tonight and post up my findings

what does the rev limiter look like.....what do ya mean by trash 'it'...the rev limiter or engine ???

do you have a measurement for the float heights ??

something is saying its not lack of fuel to me as when it dies and nearly stalls if you bring it back under the point of stalling it instantly runs and settles, no surging or anything and i would expect it to hesitate a bit before the power comes back whilst it recharges the fuel system.. !

many thanks for your assistance, it really is appreciated as i am banging my head against a wall.......and i just wanna go boatin

Pugo

 

[Dukedog]

Re: HELP mercury bridgeport problem

Rev limiter will be a rectangular black module with three wires. Black, white/black tracer and red/white tracer. They will be made up on tha switch box matching colors. Through it away..........

Don't have a clue on float "measurement". I just set 'em where I know they need ta be.

Fuel pump. Electric or manual?

Find yourself a MERC/MARINER book on your motor. Aftermarkets suck. It will save ya a whole bunch of typin'.................

 

[pugo]

Re: HELP mercury bridgeport problem

ok, its a mech fuel pump , just rekitted (after engine found not revving)

the number on the stator is 398-5454-A36

cant find a rev limiter so presuming already trashed,

pugo

ps ordered manual(seeloc or something, presuming that manual has all the info)

 

[pugo]

Re: HELP mercury bridgeport problem

An update....!

changed out stator...no difference, metered everything again after stripping and cleaning every terminal and discovered two coils not giving correct readings, so changed them out..!
put it in the water yesterday and although sounded and was running a lot better could not get over 1800rpm, however started choking the engine and feathering the throttle and all of a sudden the engine spluttered up to just over 2500rpm and then cleared and revd out all the way (after trimmimg) to 5800rpm, if i kept engine above 3000rpm it worked perfectly , however if i dropped back to tick over, she had to be choked to get back revving ??????

any ideas

Pugo

 

[pugo]

Re: HELP mercury bridgeport problem

'BUMP'

ok, gave up last year as personnal commitments took over,

so engine now has new stator,compression over 130psi on all 6, new plugs, carbs been ultrasonically cleaned and rekitted,fuel pump rekitted, reeds checked , 2x new coils, new fuel lines and all possible air leaks sorted, dropped 4 pitch's on the prop (just in case it was overpropped) and its still exactly the same, it starts, ticks over lovely, revs freely in neutral, put it in gear when its first started and it pulls straight up on the plane, but soon as its warmed up, you open it up it gets to around the 1800-2000rpm and stutters and dies, give it a squirt of choke and pump the throttle like a man possesed and it builds slowly for about 1000rpm and then its like being fired out of a gun.

i have tried everything now , i just want this working as the missus is getting the hump with me keep throwing money at it and us not getting any fun out of it ...!

any advice will be very welcome and if anybody wants to come fix it.....there is cash waiting...!

Pugo

 

[CharlieB]

Re: HELP mercury bridgeport problem

Idle mixture is too lean to allow acceleration.

Adjust idle mixture to best idle IN gear IN the water, then back out each idle mixture screw just another screwdriver blade width.

Test acceleration, any lean miss, cough, hesitation, back out each another blade width.

Repeat to perfection.

 

[j_martin]

Re: HELP mercury bridgeport problem

Hey Charlie,
Yer a little late, like about a year. I would guess he burned the bridges out by now.

 

[pugo]

Re: HELP mercury bridgeport problem

No he is not too late as i am still trying to fix this, where are the mixture screws on these carbs ? as i dont think i have any !!!!
Also i have been told that historically that these engines run hot on cyl no 2 + 5 and so as a mod the vent jets on these cylinders are left out the carbs ??? is this correct???

all help appreciated

Pugo

 

[j_martin]

Re: HELP mercury bridgeport problem

WH carbs of that era don't have any mixture screws at all. On many engines over 150 HP, cylinder 5, or 2 and 5 will have main jets .004 larger or so, as well as larger or (none) vent jets. Those two cylinders can tend to run a bit lean otherwise.

The bridgeport is named that because it has a thin bridge across a very wide exhaust port. It doesn't take much out of tune running to take that bridge out and wreck the sleeve, piston, and maybe more. Well tuned, they are screamers.

I saw your last post on the boggy run, and thought it was still last year. Don't do that. If that engine is not running perfect, don't push it. Even if it seems to run pretty well during a test run, don't push it until you know you've got it right and have read the plugs to be sure you aren't running lean in any cylinder.

You need to do the DVA tests on the stator and switchboxes just to be sure you got all the ignition bugs out. Just for grins and giggles, try a run with the bias jumper removed from between the switchboxes. If it picks up all of them, or only 1 is missing, you probably have 2 bad switchboxes.
BTW, the way to keep from throwing money at it with no joy is to do the diagnostics properly so you know which parts are bad. Changing a stator before you notice bad coils is a good example of poor diagnostics. What people say, have experienced, think, etc. has nothing to do with what is actually going on in your motor.

What you describe sounds like severe fuel starvation. That engine is a very thirsty one. If you have any crap in the tank, (I've seen an oil bottle foil, for instance) old fuel lines shedding liner rubber, plugged fuel filter, pinhole leak in the suction, faulty pickup tube in the tank, aftermarket fuel lines or connectors (They just don't deliver the fuel), get em changed out. If you haven't gone through the carbs, do it. If you find any rotting hoses, do the carbs again.

Like I said, if you starve this beast, it'll throw parts at you.

hope it helps
John

 

[pugo]

Re: HELP mercury bridgeport problem

many thanks john for taking the time to answer, i have thoroughly cleaned the fuel system including changing out all fuel lines rekitting pump and carbs, i know this problem is something simple but i am damned if i can put my finger on it...!
have done a plug chop and the plugs are a nice brown colour so although my first assumption was fuel starving, it just dont look like its running lean, its like it has a dead spot between 2000 and 2500 rpm, i have asked all the local boat shops to look at it and as soon as i mention bridgeport they all say they won't, i have a guy looking at it on the 26th hopefully but he wants it in the water to see what its doing, so i have my fingers crossed

Pugo

 

[j_martin]

Re: HELP mercury bridgeport problem

What boat is this on, and what prop are you using? Is it ventilated?

What carbs are on it. Numbers off a carb will help. Should be a xx-xxxxx number on the idle port cover plate that is the best clue.

Obviously you inheritted the problem. Do you know any (truthful) history about it?