Cleaning carbs.

[Linkedit]

I’ve just about got my carbs ready for a soak and clean while I get the new gaskets. But my dad asked if they were a full kit or just the gaskets. I told him I’m pretty sure they’re just the gaskets.

did I order the wrong parts? Should it be a “complete kit”?

I assumed I could re use the pieces in the carbs just needed new gaskets for the reassembly.

would I need a kit with a bunch of parts, or just the gaskets?

this assumes all the parts are in working order.

1970 650 thunderbolt,

thanks for all the help.

 

[ThomW]

The answer depends on the condition of your carb. I have rebuilt many carbs with just a gasket kit. However, you may need more parts or a complete kit depending on your carb's condition. Is the float okay? no cracks and not filled with gas? What about the float needle? is it in good shape? The rubber tip okay? seating properly? As long as the other parts are good, and you are soaking everything well--minus any plastic or rubber parts--then a gasket kit should be fine to rebuild them.

 

[gm280]

Too many times a "complete kit" has parts in it for a lot of different models that are not even used for your carb model. And the above comment stated it perfectly. Really depends on the condition of your carb. Usually you don't need new jets and such and a gasket kit suffices. But even a gasket kit most of the time comes with a new needle. At least in my rebuilding efforts they have. JMHO!

 

[Chris1956]

Do yourself a favor and install new gaskets, inlet needles and seats and floats. The original floats are dissolved by today's alcohol gasoline. The original inlet needles are bad by now.

They are pretty cheap, and you know you will have good performance out of them. Make sure to set the float heights correctly.

 

[Chris1956]

Mercury usually sold gaskets, floats and inlet needles and seats separately. So make sure you order what you need. Do not assume a "kit" has all the pieces.

 

[gm280]

I see so many using ultrasonic cleaners now. And I have to admit, it does seem to work very well. All the years I've rebuild carbs of most every type, I never used an ultrasonic cleaner. But I have been thinking about getting one. Does anyone know of a good one for carbs? That would be a great idea to make sure all passages are open and ready to rebuild with new gaskets and such.

 

[Linkedit]

Thanks for the replies. Got it all back together. Looks like someone else must’ve replaced float needle and seats. All looked quite good. Carbs looked pretty clean, but the amount of junk in the buckets I soaked them in was quite shocking. Should mount them tomorrow and set everything up.

Seems as though the last person to take them apart used some loctite on some of the screws, I’m assuming this isn’t normal practice?

thanks for all the help.

 

[Chris1956]

A lot of Merc carbs had some stuff to seal the brass plugs over where holes needed to be drilled in the carb body casting to install the main nozzle and idle restrictor tube. I would recommend wifey's nail polish in "Naughty Red", as it is the best.

 

[Linkedit]

Is a link and sync a mandatory procedure after these are installed. I got them all cleaned and put in place. just wondering if it’s a necessary thing to adjust the timing? Can I just check it and see if the cylinder gets the spark at the correct degrees and that the carbs are opening all the way? I have the clymers manual bust am a little nervous trying it out since this has been a huge learning curve.

Wife had a funny look when I was looking for nail polish for this “endless” project as she describes it. Lol.

 

[Chris1956]

If you haven't changed the distributor settings, you probably do not need to link and synch, except for the carb setting. That can involve adjusting the throttle stop and throttle cable.

It would be best to verify the idle pickup timing and the max spark advance, as well as throttle stop settings.

 

[Mark ofs]

The manual I had recommended using "Gasketcinch" or equal for the sealer...

 

[Linkedit]

Well took it out today, and sure sounds a bunch better, tried a few take offs, does take off better than before it gets to the 3000rpm quicker but not over it. Should I be checking some electrical? If I run it in muffs at home can I check the timing with a light? See if it’s firing at the correct dregees. I believe it’s 7-9 degrees BTDC For primary throttle pick up and 38 dredgers for timing which I think is before the secondary throttle pick up. Is also only seems to idle at 400 rpm. Should it be idling at the 550-600 rpm that’s recommended for the idle then check the timing? I have only really adjusted the idle screws to half a turn out from stumble then another 1/4 as that seems to be where it runs best.

 

[Mark ofs]

If checking on muffs do not run above idle speed....not sure your recommended rpm's would be, best to check in your service manual.

 

[Linkedit]

Thanks for that. I figured the timing would be done at an idle, I guess the carbs open a little for the timing which could bring it up a fair bit.

well thanks for the help folks guess all my questions are best in another thread not about carb cleaning, since that appears to be a success ( I think ).