Carburetor probs. 1995 416 H

[Jason Hunt 3]

My horse has the emissions carb with the accelerator pump. When at idle it pours gas in the carb and stalls out but when she is all warmed up hot she idles just fine. Im thinking about first trying some seafoam and letting it hot soak. Ive got both repair kits from Onan Im waiting on in the mail which were expensive. Got a couple of questions will brakleen in the red can tear up my rubber in the carb/accelerator pump? Should I pop the blank off the idle screw and try and adjust that first? Or should I tear the top off the carb and take out the idle needle and make sure their arent any plugged holes sprayer down with brakleen and blow it off with air? Any suggestions would greatly be appreciated. I'm kinda scared to tear into it as Im not much of a mechanic and Im new to this forum. However, Ive been peeping this site and I gathered enough info to purchase the right kits and have the know how on where everything is located in the carb. Just worried Im gonna drop something like that little choke linkage wire or the spring and the bb or the float needle valve lol

[Jason Hunt 3]

Oh also it only has 420 hours on a working meter!

[Skwerl58 634]

Concerning the Brakleen I would go get some carb and injection cleaner. I used some generic non chlorinated brake cleaner on the outside of my Kohler carb to cut gum and crud off and it ruined the bowl gasket and o ring.  I also used some CRC gum cutter on another carb and it it also ruined the same gasket. These gaskets were un-usable because they swelled.  From now on I will remove all my seals and gaskets before cleaning my carbs. I have used brake cleaner and will continue but not until I know that the carb seals, gaskets, or plastic have been removed. If you can get the jet out I would definitely try cleaning it and also adjusting it.  Others with a lot more experience will chime in soon. Hope you get your problem solved soon. 

[953 nut 51,736]

10 hours ago, Jason Hunt said:

will brakleen in the red can tear up my rubber

It will.

What should you not use brake cleaner on? To prevent damage and discoloration, avoid using the brake cleaner on plastic, rubber or painted surfaces. Read the user manual for the product before use to avoid damage.

[lynnmor 6,795]

In order to clean the carburetor properly it needs to be removed.  If you have a plastic limiter on the idle mixture screw you don’t have the emissions carburetor, if the screw is buried under a plug and there is an accelerator pump you have the emissions model.  In any case, the idle mixture screw needs to come out to clean in there.  There is a Welch plug just above the idle mixture screw that should be removed for complete cleaning, but you can try it first if you want to take the chance.

[Jason Hunt 3]

Thanks guys! I guess I'm gonna get a safe non chlorinated carb/injector cleaner to spray it down with. Im gonna try to remove the top of the carb first and do a half fast cleaning and replace the float needle and see if that doesnt do it. Dont really wanna mess with taking the intake and exhaust off it having to buy more stuff but I will if thats what it comes down to. I really like the power this Onan offers its got a 42" side discharge and it cuts like a dream! It sure likes its gasoline though (I only buy non-ethanol for now) as it takes almost two tanks to mow my parents yard. It came with a snowthrower too that I gotta figure out soon.

[Jon Paulsen 282]

Welcome here, Jason!

 

If you can, get some very slightly abrasive thing (like a Q-tip) wet with a bit of that carby cleaner, then spin it around a little on the seat that needle valve's needle tip meets up with. Her job is to cut the gas supply to the float bowl just when there is enough gas in the bowl. If you get a new needle in the kit, I think it's best to use that new needle. The tip of that needle mating with her seat above it in the bowl o' gas is the only thing keeping that evil gas supply from doing what it loves doing: filling your crankcase oil with gas. 

 

If your carby kits(s) have a replacement needle (for the in-bowl needle valve), I think it's best to use it. Remembering to cut off the gas supply after each run is the only thing keeping the gas from over-filling the bowl, pouring into the carby, and mixing with the oil in her crankcase. Get the removed needle into a baggy, date it, drop it in with the rest of the rebuild kit. Just in case. 

 

Generally speaking you use the brass tipped needle on a soft seat, the soft tipped needle on a hard seat. Many kits are sold to work with many models of carbs... there may well be some parts in the kit(s) you won't need. Listen to others here before me. I've never worked on a Kohler, short of changing my neighbors stuck spark plug for him. 

 

Good luck and let us know how it goes!

 

~jon

[lynnmor 6,795]

Non chlorinated means that the product doesn't have the chemical that destroys the ozone layer, it also means that it is a very poor cleaner.  Your Onan will run just fine on regular grade gasoline with 10% or less ethanol, the only concern is old fuel line that probably needs to be replaced anyway.

[peter lena 8,072]

@lynnmor  agree with you on the line replacement , amazed to see  many think that a fuel system is a SPOT FIX , nothing could be farther from the truth.  if you consider the fuel tank debris , fuel filter , fresh line , drop carb bowl , another filter , insuring a clean debris free refill , learned that a long time ago . agree that ETHENOL , fuel does break down fuel lines, but unless you  completely refresh that fuel flow set up , its back . own experience , for zero fuel hose break down, is  STABIL , fuel storage treatment , in every tank top off , started doing that on a line replacement years ago , experimenting . no fuel line break down at all , started that after a  complete line change , new tank valve etc. .  nothing in my filters ,  no debris in my carbs , instant starts . is that telling you something about a line break down change ? add about 1, 1/2 Oz  of Stabil to  every fuel top off . heard all the negatives on this , if so , WHY IS IT WORKING FOR ME ?  no fuel hose debris in my filters . plugs are clean . always trying something , pete  

[Jason Hunt 3]

@lynnmor You wouldn't happen to know the size of the welch plug would you? I have no calipers. Will I need a set of welch plug tools to instal it? I understand that it is supposed to have a little sealant on it, but, what kind? Also would anyone happen to know the factory settings on the non-emissions carb? I purchased a used one off (pre emissions) of e-bay that I plan on cleaning up just in case I can't get the carb thats on it righted.

[lynnmor 6,795]

4 minutes ago, Jason Hunt said:

@lynnmor You wouldn't happen to know the size of the welch plug would you? I have no calipers. Will I need a set of welch plug tools to instal it? I understand that it is supposed to have a little sealant on it, but, what kind? Also would anyone happen to know the factory settings on the non-emissions carb? I purchased a used one off (pre emissions) of e-bay that I plan on cleaning up just in case I can't get the carb thats on it righted.

I believe that they are 3/8".  I use a very small amount of  Permatex MotoSeal 1 on the edge.  Use an aluminum welch plug and install it with the convex side out using a punch to slightly flatten the dome, if you go too far it will loosen again. You should be able to find settings and procedures in the Onan Service Manual.

 

 

[Handy Don 10,614]

10 minutes ago, lynnmor said:

I believe that they are 3/8". 

That's what i used.

I used a 5/16” punch to flatten since I don’t have the specific plug setting tool.

[RED-Z06 2,120]

Ive converted all my "pumper" emissions carbs to the non-epa adjustable carbs and ive found they run much better.  My 318 Deere has a newer Linamar Replacement engine that had a pumper carb and it wanted to load up at idle no matter what.

[Jason Hunt 3]

Thank you gentleman very much for the insight and info!

[Jason Hunt 3]

You're not gonna believe this but I ran a bunch of seafoam in the tank and then hot soaked the carburetor with the spray and now its idling like a champ. No more flooding out and stalling at idle! I got lucky. However I bought all the gaskets and and a pre emissions carb for it Im gonna rebuild and put on it when the weather is nice.