Carburetor Rebuilding Assistance Please

[jviss]

First, I've 'rebuilt' many carbs, from 60's Mustangs to Honda motorcycles, to stripping, cleaning, and reassembling the one in question here: pre-2001 Mercury 15 HP, two cylinder, two-stroke outboard. I have two of these motors and thankfully they take the same carb kits.

As I mentioned, due to allowing gas to gunk up with time, and the occasional mystery 'something' clogging them up, I've torn them down and reassembled them several times, with good results. What I do is completely tear them down; soak the body in an industrial carb cleaner, the kind that's in a one gallon pail with a parts basket; wash with very hot, soapy water and rinse; dry, blowing out the passages with compressed air; reassemble with all the original parts. If it's on the boat, I just clean out the body with Gumout spray using the supplied straw.

I bought carb kits at the discount price of $59 each (ouch!). They have lots of parts, but don't include the main jet or jet holder, much to my surprise and chagrin.

In addition there are a couple of tiny, cup-shaped, brass plugs. I imagine these are so you can pull the old plugs to aid in cleaning out the carb body, and you would need new plugs.

In fact, there are a lot of parts that I wouldn't think need replacing, like the return spring, idle screw, float 'bracket' I guess - the thing that the float pushes on to close the float valve. This part is, remarkably, not on the legend; it appears the exploded views were relabeled, and it got left out. But, you can't just order the wear items.

There were no instructions included. I have the motor service manual, but nothing in there on how to rebuild the carb.

Do you know if there are instructions for rebuilding this carb? I can't find any.

How do you remove those old plugs?? I was thinking a tiny drill and a tiny Easy-out, but I don't want to wreck the carb body.

How do you press the new plugs in? Make a little punch that just fits? Maybe a little dowel?

How about removing and replacing the float valve seat?

Anything else?

Thanks very much!

jv

 

[caguy]

You should be able to pull them out with a pair of pliers. Sometimes the get blown out when blowing out the passages. They'll shoot across the garage like a bee bee gun. You can replace with a small hammer. I have aHa reused the parts an never have bought a kit. The jets are never damaged unless someone does something stupid. Good luck.

 

[jviss]

You should be able to pull them out with a pair of pliers. Sometimes the get blown out when blowing out the passages. They'll shoot across the garage like a bee bee gun. You can replace with a small hammer. I have aHa reused the parts an never have bought a kit. The jets are never damaged unless someone does something stupid. Good luck.

Impossible - these things are like the size of a grain of rice, except shorter.

 

[Steve Dion]

We got a rebuild kit for our Tohatsu/Nissan and it also did not have jets. We used a pin/needle and chemicals to clean them out. It runs better than it had for the last 5 years.

 

[kloudie1]

JV, didn't know if you'd seen these guys.. http://www.maxrules.com/index.html
They might be able to walk ya thru some of the hairy parts of the rebuild.. The little "welsh" plugs .. drill the middle and insert something like a small phillips and push sideways and lever them out.. The new one goes in dome side out and is set with a punch about half the size of the plug. Ya smack it in the middle and it mashes a little of the dome and makes the sides expand out to the walls .. kinda like a core plug in an engine block, only much smaller.. In some carbs, opening those plugs is the only way to clean the passages. Good luck with the rebuild..
EDIT.. don't pull the welsh plugs unless ya can't get the passages clean any other way..

 

[Bill Roosa]

Those plugs are not intended to be removed. They plug a passage that was drilled through to get the angle on the hole. Removing them does not accomplish any thing BTW except to introduce leaks. If you can't blast it out with gumout then it ain't intended to come out.
If you are having lots of carb pluggage problems check the air filter and the seal around the air intake prior to the carb. It only takes a little bit of dirt and a small tear or flange that does not seal well could be the problem.

 

[jviss]

Those plugs are not intended to be removed. They plug a passage that was drilled through to get the angle on the hole. Removing them does not accomplish any thing BTW except to introduce leaks. If you can't blast it out with gumout then it ain't intended to come out.
If you are having lots of carb pluggage problems check the air filter and the seal around the air intake prior to the carb. It only takes a little bit of dirt and a small tear or flange that does not seal well could be the problem.

Then why do they supply plugs with the rebuild kit?

 

[anchorclanker]

They supply the plugs for exactly the reason imagined. They ARE meant to be removed, there is no other way to clear the passageways they cover. You carefully drill a small hole, slightly off center is usually best, and carefully, using a small pin punch or similar small tool, pry the plugs out. After cleaning, you insert the new plug, concave side outward, and with a small flat faced punch, tap the plug down semi flat to expand it into the hole.

Rebuild kits dont, as a rule, supply jets, they are not a wear item. You may be referring to the needle and seat, the parts the float operates to control fuel? Those may or may not come in a kit. They should, but dont always.

 

[Benny17441]

I have cleaned, rebuilt and installed many carburator kits and have never had the need to replace the plugs. Not all the parts in these kits need to be used. If one had an air leak I would replace it but if not why bother.

 

[schnr26]

I have a Honda 7.5 long shaft that runs fine with the cover off, but will only run just above idle or cut out altogether with the cover on. What's up with this?

 

[KD3PC]

I have a Honda 7.5 long shaft that runs fine with the cover off, but will only run just above idle or cut out altogether with the cover on. What's up with this?

cover is pinching, binding or blocking something...should be easy to discover with a stout visual inspection

 

[jviss]

Update on rebuild

I finished the rebuild. It took less than 1 hour including stripping and cleaning the carb. I used the gallon pail solvent, 'though it didn't work as well as in years past; perhaps it's spent.

There are a couple of tricks. There's a spring clip holding the shaft seal for the primer.

There are several pasts that are not used, including a variety of throttle spring options, plus pump gaskets.

Haven't tried it yet, but I'm fairly confident.

I don't think the kit is worth the money, as there are very few parts that actually needed replacing, in my opinion, even for this 12 year old motor. If you could just get the selected parts that would be great, but many can't be ordered individually.

Cheers,

jv