Topic: 1978 CB550K Carb Rebuild

[Jimbo4871]

Sorry.  Fix in my last posting.  replace the word "Ring" with "Bushing".  except when I mention "Brass Retaining Ring". 

[jason405]

 Ok. Simple green for the initial crud cut, dip everything I can to dissolve in tight spots, then I will hit everything with the soda blaster like jets, ports, etc, then a final rinse.

I also used my die grinder and a fine disk to knock down a couple heavy rust areas.

Got started but it's going to take a while. Will report back once I get things cleaned.

Jason


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[harisuluv]

Careful with the simple green, it can discolor aluminum.  Maximum safe exposure is about 30 minutes.

[jason405]

Ok, only using the simple green during brushing/scrubbing.  Then will rinse it clean. Still a little baffled by the o rings and felt rings on each end, and how to get them out, or clean them in place.  I guess I will just avoid those areas with chem dip and clean that area the best I can with a brush.  I will probably rig a coat hanger or something to allow the carb body to dip all but the top where those rings are.

The bodies are soaking in water/dawn mixture over night, hoping to loosen the grime, and I will hit them with a brush and simple green tomorrow and continue with dip and so on.

[Bru-tom]

http://forums.sohc4.net/index.php?topic=133302.0

[jpfrk2001]

Jason,

I am doing a the exact same type of Carbs right now. Just take your time, take LOTS of reference pics, go slow!!

Alot of the references and sites posted are all good. I will add in 4 into 1 for the secondary jets. Just have to click on the CB750 option. Use the same year. It really seams the carbs for a 78 CB750 are almost the same as the 78 CB550.

Here is what I did:
Dunk individual Carb with old parts still attached in a solution of 10% Seafoam, 10% marval mystery oil, 80% 91 octane fuel. <- for 24 hours

remove and carefully dissassembly. The carb barrel sliders might be stuck. if so, go to next soaking in- 10-15% Simple Green, the rest is Distalled white vinigar. <- for 24 hours. All the other parts will be thrown in a same, but seperate mixture.

This was to work all the gas out slowly. Remove and use heat gun to pop out the barrel/needle slider. Dunk barrel/needle assembly in same batch of vinigar with other small parts.

Replace vinigar mixture with new batch. (I have already gone through 3 gallons of viniger and a full bottle of simple green. I just started my 3rd carb yesterday)

Put carb body, float bowl, cap back in new mixture in a warm environment (inside the house is best) Scrub with non metallic brush (toothbrush).

Remove, soda blast body, bowl, cap.

dip back in Gas coctail real quick. Remove and blow off with compressed air.

Reassemble

enjoy!!

Note: this is what I did. There are soo many methods. This worked best for me. As I was not in a rush, and I did not damage one thing during the entire process.

[jason405]

Hey guy,  just a little update.  Cleaning is going well.  I have removed the bulk of the grease/grime with soap/hotwater, and simple green.  The small cracks and recessed areas are obviously the hardest.

I am going to try the soda blaster on the bodies to see if I can clean those tight areas. 

I am still looking two more of these needles and springs.



Also, I understand these are suppose to have a flat washer between the spring and o ring on all 4 needles, but none of mine had the washer. 

So technically I need, two needles, two springs, and 4 washers.

I'll post some more pics after soda blasting.

Jason

[Maurice]

I have a bunch of these washers. Send me your mail address I'll send you some. You'll need the o-rings also, I don't have any extra, but they should come in rebuild kits easily enough (as opposed to the washers).

[Jimbo4871]

Yup, that's the airbleed screw.  Jason, I'm willing to bet the washer and O-ring are still inside.  you need a needle like very fine flat head screw driver, magnetic if you can find one, and dig it out.  If you are sure they are not in the holes, if you order new needles they will most likely come with them. 

[jason405]

I have a bunch of these washers. Send me your mail address I'll send you some. You'll need the o-rings also, I don't have any extra, but they should come in rebuild kits easily enough (as opposed to the washers).

Awesome! Thanks Maurice! PM sent!

[jason405]

Yup, that's the airbleed screw.  Jason, I'm willing to bet the washer and O-ring are still inside.  you need a needle like very fine flat head screw driver, magnetic if you can find one, and dig it out.  If you are sure they are not in the holes, if you order new needles they will most likely come with them.

Hey Jimbo,

I had read about them remaining in the carb body but when I look with a light, I cant see a washer at all.  I used a paper clip to dig out the o rings and I have new ones on the way for all 4.

Now I just need 2 needles and 2 springs.  Any ideas where I could order them?

Thanks!
Jason

[jpfrk2001]

I ended up getting a complete carb kit from Crumnzige on Ebay. Had everything except for the slow jets. I had to get the slow jets from Siriusconcepts.

As for the air needle, When I took mine out, the order of the parts on the needle, from bottom to top was -> o-ring > spring > washer in that order. But hey, maybe someone else has been in these carbs and reassembled wrong? I too want to know the correct sequence on the air mixture needle.

[Maurice]

Pilot screws, they should still be available from here.

[jason405]

Pilot screws, they should still be available from here.

Great! Looks like I can order the whole needle set which will include the springs as well.

There are also a few listing on ebay for them but they are $15 each. After shipping partzilla is a little less. 

[jason405]

Ok, I ordered 2 needle sets, a set of Emgo pods, a new oil filter, and 1 new carb intake rubber boot to replace the one I'm missing. 

Once I get these carbs cleaned and back together I am will flush the engine with diesel, change the oil filter, and see if she will start!

[Jimbo4871]

Ya I would say Ebay is the way to go, but for jets, needles, and little componets of your carbs it is worth it to buy them NEW.  If you plan to get new screws for the caps and float bowls I just went to the hardwear store and got some there. 

I use this website as a refrence to map the carbs when rebuilding.  You can't buy all the parts on here but you can get little things like gaskets, and some of the jets/needles. 

http://www.hondapartshouse.com/oemparts/a/hon/506b8ba5f870023420a1e86d/carburetor-components

POST PICTURES!!!

[jason405]

Thanks is for the link Jimbo! And great idea getting new screws for the float bowls and caps. I'll go to ace.

Here's where I'm at. After making the diy soda blaster and using making soda on some other parts, I found that I wasn't getting the results I was hoping for. I bought the cheap spot blaster gun from HF and a 50lb bag of their XL soda. Man! What a huge difference between that media and regular old baking soda!

I got these results in just a few minutes. Didn't have a lot of time, so I only did this one and there are still a few spots left to get. It won't take much more time to finish this one and get the other three. 







I have an o ring kit on the way and got the other parts ordered from partszilla. I will continue cleaning and will be out of town all next week so I will plan on reassembling a week from saturday.

Thanks again for all the help and support!
Jason

[harisuluv]

You should pull the slow jet and get that passageway and the jet itself, cleaning the jet with soda blasting won't work.

[jason405]

You should pull the slow jet and get that passageway and the jet itself, cleaning the jet with soda blasting won't work.

Will do Harris, thanks!


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[jpfrk2001]

You should pull the slow jet and get that passageway and the jet itself, cleaning the jet with soda blasting won't work.

+1 and, As Harisuluv told me.. I used a set of vice grips on the slow jet with a piece of marine vyinal between the grips and the jet to protect it. He actually said a piece of leather. I didn't have any laying around to use. That was the closest piece of material I had. They will come out. These are press in jets. All this info thanks to Harisuluv

[jason405]

Ok, I just pulled one out and it looked clean, but I will be sure to pull all 4 and get them dipped/cleaned out before reassembly!

[Jimbo4871]

WOW! World of difference from the dirty pics to the post soda blasting.   Great work. 

Jason, I wouldn't bother dipping the Slow Jets.  Order New ones.  The Slow jets on those clog up with fuel deposits that are almost impossible to fully clean out.  And if a slow jet begins to clog you'll constantly have to keep re-adjusting your idle, and screwing up the other cylinders.  Just get new ones, they don't cost much. 

Stock size is #42 

Here is the website I posted before where you can order them.  http://www.jetsrus.com/a_jet_kit_street/honda_550_CB550_1977-1978.html

Also Make sure you Air Gun (NOT SODA BLAST) out the x2 brass ports on the Bottom of the intake side of the main air inlet.  One of those ports feeds air to the slow jet, and the other feeds are to the main jet.  If those get clogged with dirt, the slow jet and or main jet will not suck up fuel to feed the carb properly.  Just make sure after every cleaning, Soda Blasting, etc, you air gun those out at both ends. 

[jason405]

Thanks Jimbo!

Ya after using soda on that one carb, I rinsed it well with warm water, and then used the air gun on the whole thing. Will be doing the same thing to the other 3 tomorrow.

There are some spots where it looks like the aluminum has been etched and the soda does nothing on those areas.  Guess if that's all I have to live with in the end, they will still look night and day different from when I first got them! 

I will probably order new slow jets, but I would like to at least try the original first.  Easy enough to remove when the time comes to replace them.

Expect more cleaning pics tomorrow!

[calj737]

You can use Aircraft Stripper on those bodies too. It thoroughly cleans the exteriors and is aluminum safe. Then soda, clean, air gun.

[jason405]

You can use Aircraft Stripper on those bodies too. It thoroughly cleans the exteriors and is aluminum safe. Then soda, clean, air gun.

Ahh great idea! I might give that a try as well! Thanks calj737!