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Carb rebuild questions

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NaymzJaymz

Contributing Member
I'm "rebuilding" the carburetor on my 1980 Evinrude 25 HP with a basic rebuild kit. The carb is basically disassembled and soaking in seafoam. Low speed performance is very poor no matter how I adjust the needle. The gasket that the needle threads into had the square tab broken off, and there was no little o-ring on the needle. Is this the reason for the poor low speed idle? The motor runs wonderfully at mid to full throttle. In fact it seems that the needle was not controlling the idle at all, whether all the way in or out. How about the float? The rebuild kit comes with a new one, but is that the kind of part that wears?My shop manual says to leave the nozzle in if it's hard to remove, so it's still in the carb. There are many more parts in the kit than I will probably use, one of which looks like a little round tap in cover to the channel that the low speed needle is housed in. Should I have pryed this out before soaking it? Sorry for so many questions. Any help or general facts about this carb would be appreciated. Thanks guys.
 
Sea foam might not be the best to clean the carb, it will help keep the carb clean with regular use, but you might be better off with a spray cleaner followed by compressed air. Did you remove the core plug on top of the carb, there are passages under the plug that you should clean. Not sure about an o-ring on the low speed needle, don't think I have ever seen one. Are you using an aftermarket kit, they usually have extra parts. You normally don't have to replace the float on your engine, but since you have a new one, might as well install it.
What is your model number?
 
I think the part you are talking about is called the retainer and yes you should pry out the old one, clean up the channel well and insert the new one. This part helps seal that chamber and if you do not have a good seal it will effect your idle. Is this the part that had the square tab broken off? If it is, then you absolutely want to replace it with the new one from your kit. This may very well be the cause of your entire problem with your idle. I don't believe there is any O-ring on the low speed needle on your carb.

I also agree that you need to remove the core plug as well and clean up that chamber. Make sure you blow out all the chambers with compressed air, many, many times. You want it pristine clean.
 
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Thank you, gentlemen. I've been informed, in past posts, of the "seafoam thing", but I will use cleaner and compressed air before reassembly. The part with the square tab is indeed broken off, and it will be replaced from the kit. I mentioned the O-ring on the low speed needle valve because it doesn't look like the little O-rings in the rebuild kit would go anywhere else. Yes, it is an aftermarket kit purchased off Ebay. The other part I'm talking about is a round part that appears to be a "tap in" part. It's on the top of the carb and appears to be in the "channel" that the needle valve belongs to. What is a good way to "pry" this out and clean underneath? How about installing the new plug? My model # is E25RCSA. Thanks guys.
 
Are you talking about #5?
Two ways to get the core plug out. First way, use a drill and drill a 1/8" hole in the core plug and pop it out with a scribe.
Be careful not to go to deep with the drill bit, just far enough to go through the plug, 3/16" is deep enough.
Second way, the way I do it, just use an 1/8" punch and tap it through the plug and pop it out. The plug itself is not hard, and will deform easily.
To install the core plug, place it in the carb body DOME UP, use a large punch or something flat and just a little smaller than the plug and tap the plug flat.
http://www.ishopmarine.com/ishop/js...CatFilter=BRP&eCatSupFldr=supplier-100-005-EJ
 
Take a look at this diagram that daviet supplied. There are two gaskets that might be the ones you are talking about . #7 and #33.

http://www.ishopmarine.com/ishop/js...CatFilter=BRP&eCatSupFldr=supplier-100-005-EJ

Also, if you are using carb cleaner, use it before you install those gaskets and that retainer, since carb cleaner can eat away at plastic parts. So clean it up, blow it with compressed air and then install the plastic parts. If you fear any contamination after you have install the plastic parts, use your seafoam after that since it is OK with plastic. Always blow it out after use.
 
Wow, thanks guys for all the help. Yes according to that diagram I'm talking about #5 as Davie asked. I'm a bit skittish about taking mine out. What if the rebuild kit piece doesn't fit right? I'm probably worrying for nothing though. It sounds like I should take it out to clean, right? I am going to blow it it out with compressed air irregardless. I've been using brake cleaner instead of carb cleaner. Is that good? Would the passage be cleaned good enough after soaking and the being rinsed in brake cleaner and cleared with compressed air, even without removing #5? Thanks again!
 
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