carb rebuild...stumped...problem solved????

[medic]

I am in the process of rebuilding a rochester 2 bbl carburetor. (talked about in another post)<br /><br />Everything has gone well up until this point. Now I have a question. It has to do with the location of the fuel needle and seat above the float. I have put in the fuel needle seat and gasket and put in the fuel needle, but what holds the needle in place? In the original piece, the seat and needle are one piece. When the float dropped down the original fuel needle stayed put. Now, with the new one when the float drops down, the fuel needle almost comes out. What holds it in place? Where as the old was one piece, it is now two seperate pieces.<br /><br />Hope that made sense. Thanks.<br /><br />medic

 

[Rickbaro]

Re: carb rebuild...stumped...problem solved????

is the dimension for the float correct when it is at its lowest? The float will keep the needle in ususally

 

[medic]

Re: carb rebuild...stumped...problem solved????

No, it isn't at this time. It's off by about 1/8 of an inch, if I have the right specs. That may fix the problem, but it just don't look right.

 

[medic]

Re: carb rebuild...stumped...problem solved????

Ok. I went and adjusted the float. Since I have a 2.5 liter. I used the specs for a 151 cubic inch. My particular carb is not listed in the specs. Float drop is 1 5/8 inch. Float height is 5/8 inch. This setup seems to be doing the trick, but when the float is at its lowest point the needle is wanting to sit kinda sideways. It doesn't seem to be getting jammed though. Also when the float is at its highest point the fuel needle wants to get stuck. It will fall down however. Will the flow of the fuel force the needle down?

 

[magster65]

Re: carb rebuild...stumped...problem solved????

Set your float drop setting so the needle is still in place. The fuel pressure will keep the needle from getting stuck when it's all the way up/full.

 

[medic]

Re: carb rebuild...stumped...problem solved????

I got the carb cleaned, the float adjusted and back together. Not to difficult of a job. Took it to the boat, about 15 miles from home, and forgot the key. I went ahead and put it back on. Hooked up all of the lines and hotwired the ignition to get it to start. Took several seconds of cranking to get her going, but she fired right up. Sounded kind of rough though. Let it run for about 5 to 10 seconds and then shut it down.<br /><br />Is the rough sound normal and will it smooth out on its own after running for a min or so? I checked for leaks and think I may have saw some around the base at the location of the idle mixture screws. Is that normal too? And should it stop, if indeed it is a leak?

 

[magster65]

Re: carb rebuild...stumped...problem solved????

Not really, ideally a carb. shouldn't leak anything. I read your first post again and it got me thinkin'... your needle should either have a slot to slide into the float tab or a small spring that hooks on the top groove in the needle and hooks around the float tab. There's almost always something holding the needle in place. Look down the carb. when you shut the engine off and see if it drips. Marine carbs flood inside the motor unlike an automotive unit that spills outward.

 

[denniz]

Re: carb rebuild...stumped...problem solved????

Are you really a paramedic? ... DAM

 

[hoot]

Re: carb rebuild...stumped...problem solved????

just did my 2bbl rochester. the float has a small slot in the arm for the needle to attach to. the needle had a small clip attached to the end that fits in the slot. fits loosely but works, set drop and level correctly. no leaks allowed, will not stop on their own. check the gaskets. scrape off all old gasket material before installing new ones. be sure all screws and bolts are tight. and this note - brass floats should never have a hole in them!!

 

[medic]

Re: carb rebuild...stumped...problem solved????

Rod Knocking, <br /><br />Yes I am a paramedic. For almost 10 years. Man, I am getting old. EMS for almost 14.<br /><br />Hoot,<br /><br />I did have a clip, but was not sure where it went. Now that you and magster65 have mentioned it, it looked like it fit on the fuel needle.<br /><br />I went back and worked on it some more. Looks the that leak is coming from around the gasket between the base and bowl section. I took the carb off and tried to tighten those "3" screws some more without much luck. If it still leaks then what. <br /><br />It seemed to idle rather well at first. I gave it some gas and then backed it off to idle position, but the engine rpms hung arond 2000. Think that clip on the fuel needle is the problem? I did not see it referenced in the instructions. <br /><br />I then shut it down and backed it into the garage. Frustrated! May take it to the boat shop after all.

 

[medic]

Re: carb rebuild...stumped...problem solved????

hoot, <br /><br />about that clip. did your fuel needle have that clip on it already or did you have to attach it to the needle. after on the needle, what about the float. does it go around the arm of the float or is there a hole for it to fit into?<br /><br />how much pressure/force did you use when mounting the carb to the intake?<br /><br />thanks<br /><br />the float is plastic. no holes in it that i saw

 

[rabidfish]

Re: carb rebuild...stumped...problem solved????

As a dealer for over 20 years, i am compelled to express my opinion here...<br /><br />I admire your desire to fix this yourself. & i must say the "do it yourselfers" in my area are a good source of parts sales income for me. <br /><br />BUT !<br /><br />For the sake of safety here, seek out a qualified marine technician. Fuel leaks are dangerous! having a poorly repaired carb can be even more dangerous in certain conditions. a carb overhaul should not cost more than $200 - $300 at the worst. heck, send it to me & i'll do it for free if you supply the parts. anything is better than getting friends & loved ones injured...

 

[medic]

Re: carb rebuild...stumped...problem solved????

The link is a picture of the float and metal arm. Is the hole in the arm where the pin for the fuel needle goes? The pic is before I rebuilt it.<br /><br /> float

 

[galaxy]

Re: carb rebuild...stumped...problem solved????

Medic,<br /> If you still have a leak after installing new gaskets, it's possible you may have the wrong gasket on there. For example, your gasket may look like it goes there, and would ,on another style carb, but in one area it may not seal over...let's say a fuel passage. Go back and double check your gasket(s). As for the needle...<br />If I remember correctly it should fit over the rear of the float tab. You'll think..How could it stay on?...but it really can't go anywhere once the bowl has fuel in it.

 

[hoot]

Re: carb rebuild...stumped...problem solved????

i bought a rebuild kit from the merc dealer, about $25. it had a needle and seat in it. the needle had a small wire clip attached. from your picture, my clip went into the small slot you are showing. this connection makes sure that the needle comes down when the float comes down and helps hold it in place. my kit had several gaskets included to fit different carbs. some gaskets were not used, you have to match up the correct ones. the 'force' used to mount the carb to the manifold, i would describe as very snug. did not have a torque wrench. it is important to snug the nuts as close to the same amount. if you are not comfortable with the rebuild, take rabidfish up on his offer and send him $50. there should be no leaks anywhere around the carb when done.

 

[medic]

Re: carb rebuild...stumped...problem solved????

why..why..why...?<br /><br />I went over after work and tore the carb apart. Put in the clip for the fuel needle/float, recleaned mating surfaces, checked gaskets and put it back together. It started up fine, runs perfect. Figured out why, after revving up the engine, that the rpms stayed high. Adjusted throttle cable. Now...it idles perfect, revs up and down, comes back to a nice smooth idle and no leaks....until.....<br /><br />I only ran it for a min. No water to cool as I am working in the driveway. Watching temp gauge. Then shuttin down.<br /><br />Now, after a few minutes with it shut down, I see a film of gas around the idle mixture screws. why...why...why? I knew I should have left those screws alone. I had went and talked to the mechanic before working on the boat today and he could not explain, right off hand, as to why gas is coming from around those screws. What gives? The gaskets are turned correctly. Checked and double checked before putting the carb back together.<br /><br />Is there a gasket or some type of thread tape (teflon tape) that is supposed to go on those screws? Will it varnish over and stop? aarrgghhh!<br /><br />these parts were left over<br /><br />I took a few pictures of before the rebuild and have been looking at them. How would gas even get to those idle screws?<br /><br />Thanks guys. This is bugging the h*** out of me.

 

[denniz]

Re: carb rebuild...stumped...problem solved????

OK... Not sure about your fuel leak but now that YOU have run the boat for 1min. without water your going to need a impellar. Thats the water pump in the drive. Please take this thing to a shop. Do you know that you temp guage doesnt work if there is no water in the motor? It measures hot water not hot air. Your costing yourself money by working on it yourself. NOW you need a $200. carb job and a $150.00 waterpump PLUS parts.

 

[medic]

Re: carb rebuild...stumped...problem solved????

Sounds like I screwed up. There should be water in there, since it has been on the lake a couple of weeks ago. The temp guage is working. At least it is moving. But never the less, I am Done! Thank you.

 

[denniz]

Re: carb rebuild...stumped...problem solved????

Yeah Medic you screwed up but 50% of boat owners do the same thing. Stay safe being a paramedic. Hats off to you.

 

[hoot]

Re: carb rebuild...stumped...problem solved????

you may not have done much impeller damage. you will need to go out into the water and watch the temp gage(get the carb leaks stopped first). if you want to be a DIY'er, get some outdrive muffs and an owners manual (i recommend Seloc). my idle screws have springs on them to keep them in place and tight. and gas does go into that area. maybe your threads are worn out. shop mechanics will not tell you much when asked. this forum is better. boats are just another money pit.