mercruiser 3.8l v6

[Canboatman]

last year I experienced issues with this engine, loss of power, when i would hammer the throttle it would die. it would come back to life if i let of the throttle. i had a real hard time getting it to hit max rpm. naturally i figured a fuel problem, so rebuilt carb, new filters lines cleaned out the tank nothing seemed to make a difference, thinking now it may be a ingition prob?? still have the origional points in it looking for any pointers, I'm kinda stumped and the spring is coming soon thanks

 

[dubs283]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

thinking now it may be a ingition prob?? still have the origional points in it looking for any pointers

i would start with a tune-up and go from there

are you sure it has a points ignition??

 

[Don S]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

The 4.3 has been used by Mercruiser since 1985. Believe it or not, the 1985 is nothing like the 2012 model. Like cars and trucks, things change from year to year. Do you have a model number, serial number, or even a year to help us figure out what you have?

 

[eclipse196]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

Need a little more info. What year is it? You said carb, so I would guess it is an older engine.

 

[Canboatman]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

ya its has points, its a early 80's i believe maybe 84 or 85 its rated at 185hp has a rochest 4 barrel carb

 

[Bondo]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

Ayuh,.... Did ya check the fuel pump output, 'n pressure,..??

 

[achris]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

ya its has points, its a early 80's i believe maybe 84 or 85 its rated at 185hp has a rochest 4 barrel carb

4.3 litre V6s never had points. In 83-84 Mercruiser did do a 3.8 litre (229 cu in) V6 which did have points, and it was rated at 185hp, and had a 4 bbl Rochester Quadra-jet carb.....

The most important thing to remember with these engines is that they are an uneven firing engine, so you can easily get the distributor back in the wrong way. It will 'time' ok on #1, but the even cylinders will be out. That said, it does sound like you have a fuel problem, mainly carb set up. The Q-jet carbs are VERY finicky to set up, and you need to get it 100% right or the carb just doesn't work....

Got the manual?

Chris...........

 

[dubs283]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

carb work??

the op said he rebuilt the carb and cleaned the fuel system, filters, etc...

am i the only one who saw "still has the original points in it"??

dunno about everybody else here, but points that are close to thirty years old get replaced in my shop

in fact, i recommend replacing points, filters, plugs, cap/rotor, etc... every two years under normal operating conditions

 

[achris]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

..

am i the only one who saw "still has the original points in it"??...

I think he means it still has the original points ignition system, it hasn't been converted to electronic ignition (which is what I'd do). I doubt the points themselves are original... That would be silly.... :facepalm:

 

[CharlieB]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

Bogging and dying on acceleration, recovering if the throttle is immediately pulled back is often a sign of an accelerator pump failure.

With the motor turned OFF< remove the spark arrestor, disconnect the throttle cable, if the choke is closed use a small wire to hold it open, look down the carb throat and open the throttle fully.

Did you see the accelerator pump squirt down the primary side throats while the throttle was moving open?

If not, remove the carb and go thru it again, double check the accelerator pump check valve and pump seal.

 

[Canboatman]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

i've been told by my local marina its a 4.3 the motor and drive came out of a 85 thundercraft now in a 91 sylvan. i know forsure it has points in it, not sure if origional. i know i have never changed them in the 4 years i have owned it. the reason i am thinkin ignition not fuel at this point is after all the work on the fuel system it still ran 100% the same way as before??

 

[Technorunner]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

If you have that old points. In 3 steps start with check timing on the engine step 2 change points and condensor and adjust the points properly. Step 3 Check timing on the Engine again and verfy its right.

 

[achris]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

i've been told by my local marina its a 4.3 ...

Post the engine serial number and we'll check it for you, but if it has points, 99.9% chance it's a 3.8. Not many made and so there are plenty of people who don't even know they exist, they think every V6 is a 4.3....

Chris......

 

[Canboatman]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

thanks for all the advice so far, over the weekend i will try to get the #'s of the engine

 

[Canboatman]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

just pulled boat out checked serial #'s it reads mcm185 6776858 229cid looking at this i'm thinkin that maybe i do infact have a 3.8l not a 4.3 any advice would help. are these still good engines? still i need to fix the issue i was having last year just don't know what to look at thanks

 

[Bondo]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

still i need to fix the issue i was having last year just don't know what to look at thanks

Ayuh,... The Points,....

post some pictures of yer motor, 'n distributer....

A 3.8l ain't quite the end of the world,...

 

[Canboatman]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

is there a elec. conversion kit available for these engines?

 

[Pete104]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

You don't need a frickin conversion! Less people can fix them!!!

 

[dubs283]

Re: mercruiser 4.3l v6

Re: mercruiser 4.3l v6

still i need to fix the issue i was having last year just don't know what to look at thanks

read this:


http://forums.iboats.com/showthread.php?t=335302

 

[Canboatman]

Re: mercruiser 3.8l v6

thanks, read that and i will pick up the parts and give it a go seems fairly simple. next question is it at all common for a fuel pump to go bad? i still have it in my head that it may be a fuel issue!!!