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1989 Mercruiser 4.3L - fuel related problems

Only thing i can think of is you may have the needle clip wrong.

Can you get some pictures of float and needle showing the little clip and how you have it attached to float?
 
Final theory, both the new and old seat are bad, not the rubber part but the metal piece. The new one looks obviously bad with many scratches, the old one, I think there is a small hairline scratch.

Edit: in my 3rd imagine, now that I look at it you can see what I mean it looks bad.

So maybe third kit? Third times the charm?
 
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kghost said:
Oh this carb doesnt use a clip to hold the needle to float...
Thinking of other carbs...
Click to expand...
I think my 1990 mercarb had a clip holding the needle to the float. if i can find a pic of the rebuild i did years back ill post it

to the OP the carb is not junk one of three things is happening:

1. float is heavy due to absorbing gas, replace it if you haven’t. When i rebuilt my mercarb the float cracked when i touched it to take out the pin.
2. float is getting hung up either pin two hangers float or air horn gasket etc is catching the float
3. needle and seat is getting hung up. If you did really pay $11 for a carb kit what did u expect?

check to see if it operates smoothly up and down or catching on the bowl as you put it together. My advice buy a float and needle and seat from a reputable supplier. With the proper parts this should be an easy fix.
 
I stand corrected no clip float to needle

here is a link to 1 or 2 mercarb rebuild videos, link to video 2 will pop up when u play this one

is the float hanging up on the baffle that slides into the airhorn ?
 
I'm looking to get another kit, since they are not that expensive. I know the float works but I will end up replacing it anyway. I'm just confused how it didn't leak when I put the top upside down. I would think the gas pressure in the bowl would push the float up with the same amount of force if not more. (Float is 9g I believe)

Dieter said:
If you did really pay $11 for a carb kit what did u expect?
Click to expand...

idk it was cheap and I thought why not. I should know better.
 
The pic of the seat, looks off, not seated all the way.
A gap beteewn body and washer....
Am i imagening this???
 
Never has leaked from there, I actually found a better washer that fits, not perfectly, but slightly better. I also found out that for some reason there was 2 washers on the power valve. The first washer is seized in there so I can't get it out. But that doesn't fix my main issue still.
 
Joey White said:
Last night I just was testing the needle and seat, so I put the top of the carburetor upside-down, turned the pump on, and there is no leaks. I even left it overnight pressurized with some fuel like that and when I came out in the morning to it, it still had fuel pressure. But it always ends up flooding when I put the two half's back together, so basically when I can't see what is happening. First time I put the half's together, it flooded, float was to spec on all the heights, so I adjusted the float level way more then it says on the sheet. Then for once it didn't flood, held it for a good 30s then I emptied the bowl to make sure... And it flooded again... so either I'm doing something really wrong, or this carburetor is really just junk. I would just buy a new carb to solve my problems, but that's expensive and I have a limited budget of not spending money if I have to.
Click to expand...

Did you install a new float?
Is the old float brass or black foam?
If the float is brass and has a hole in it, the carb will flood over...
If the float is black foam and saturated it will not be buoyant enough to close the inlet needle.
 
If i remember correctly, When ordering a carb kit you need to order by the carb number.
Do you have the carb id number? It is on the casting of the carb

If we can sort out which kit is correct (if by chance the one you ordered is incorrect) we may be able to make some progress. (assuming that the previous comments about the float prove not to be the problem)

I do not like the looks of the seat and how it does not appear to sit flush on the washer. It may be the picture but it does not look right to me.

The carb number should look like these...

abc.jpg
 
Docksidemarineservices said:
Did you install a new float?
Is the old float brass or black foam?
If the float is brass and has a hole in it, the carb will flood over...
If the float is black foam and saturated it will not be buoyant enough to close the inlet needle.
Click to expand...

It is the black plastic float, same that came with the carb when I first took it apart, I have tested two new floats and they both float good and have no leaks.
 
kghost said:
If i remember correctly, When ordering a carb kit you need to order by the carb number.
Do you have the carb id number? It is on the casting of the carb

If we can sort out which kit is correct (if by chance the one you ordered is incorrect) we may be able to make some progress. (assuming that the previous comments about the float prove not to be the problem)

I do not like the looks of the seat and how it does not appear to sit flush on the washer. It may be the picture but it does not look right to me.

The carb number should look like these...

View attachment 26238
Click to expand...

I can agree the washer just doesn't fit the seat.

The carb # is - 3304-9565

Which is the same made for this motor according to this page:
https://www.carburetor-parts.com/assets/images/K529.pdf

That website is also the same page I have been getting all the adjustments for the float from.

But I should add that that is not the number on the carb. The number on the carb is impossible to read, but that # was on one of the screws as a little metal tab saying 4.3L and 3304-9565. So I'm guessing that is from when this carb was rebuilt way in the past. But it defiantly needed rebuild again anyway, since it was super dirty inside.
 
From what I can find,

The Amazon list link below contains a $12:00 kit...............I must say that price is very suspect.......


This web site, a MERCRUISER Kit is $ $75
Mikes Kit is $40
Amazon's Sierra kit is $50.00

Based on the HUGE price difference between 12 and 40.............not sure you got good stuff. Of course I cant say for sure without physically see and handling the parts but it makes one suspicious..............


For carb # 3304-9565


This web site: http://www.marineengine.com/newparts/part_details.php?pnum=MER3302-804845

Mikes Carbs: https://www.carburetor-parts.com/Mercarb-Carburetor-Kit--PK112_p_3483.html

Amazon-Sierra Kit: https://www.amazon.com/CARBURETOR-K...02-804845&qid=1613936351&s=automotive&sr=1-10

AMAZON, list of kits: https://www.amazon.com/s?k=Mercarb+kit+3302-804845&i=automotive&ref=nb_sb_noss
 
Send me the carb...all your parts. I will rebuild it for free, just pay return postage. I'll send you some food and water too. You guys have been brutalized.
 
timguy said:
Send me the carb...all your parts. I will rebuild it for free, just pay return postage. I'll send you some food and water too. You guys have been brutalized.
Click to expand...

PM sent

Anyway, it took me a day or two. But I've been thinking out my options. So far I got the carb as best as I ever have. But that doesn't mean it is fully good. At 5psi the carb barely drips, instead of completely flooding it self it drips a drop every second or so. But I know that even that small of something would cause the boat to run too rich. Besides that if timguy is still available with his offer that is looking like the route I will take. Unfortunately I need to take a break from the boat again because I notice there is a large amount of gas in the oil from it flooding so much. I don't want to keep trying to run it with that so I am going to try to change that oil this weekend if I can, but most likely I can't because it will be raining the whole time.
 
Yes, get that oil out of there. I'll be right here....been here for eight years. Spending more time on the forum now since I'm retired and it's winter too.
 
timguy said:
Yes, get that oil out of there. I'll be right here....been here for eight years. Spending more time on the forum now since I'm retired and it's winter too.
Click to expand...

If you could private message me your address, I could send you the carb as soon as I can.... If I can find my wallet.
 
Report on carb. It was a mess, hope it works now. This was a job that really couldn't have been easily fixed. I thank all my mentors and peers here for their help to Joey. The accelerator pump was wrong, carb air cleaner/spark arrestor castings all broken off. Worthless plastic float, wrong power valve included, incorrect needle seat washers included, choke butterfly binding....not fully closing. Sure hope it works, JoeyIMG_20210319_145425071_HDR_compress23.jpgIMG_20210319_144616212_HDR_compress62.jpgIMG_20210319_165326499_HDR_compress55.jpgIMG_20210319_185546232~2_compress27.jpg
 
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