Author Topic: 627B Carb Rebuild Pics (Read 4282 times)

btripp · « **on:** November 02, 2005, 07:18:15 PM »

Hi guys,

Here's some pics of my carbs. I just got them off tonight for cleaning. For crying out loud, somebody please, please tell me they're easier to get back on than to take off! Well, I guess they had been on there sitting out rusting for years so I guess it figures they'd be hard to get off.

I'd like your opinion of the rust on the outside of the carbs, particularly on the throttle mechanism. You'll note that there is also some rust inside the carbs too. I tried to look down into the engine through the intake, but couldn't quite make the turn. There was a little rusty fluid (probably WD-40 used to break them loose) and a few deposits in the outside right hand intake. I don't know if water got in there, but at least some probably did. I don't plan on tearing down the engine, unless I have to. All the other intakes were clean.

In the next few days I'll be taking the carbs apart and I'll post more pics then of the insides.

Thanks for all your help!

-Ben

SteveD CB500F · « **Reply #1 on:** November 03, 2005, 01:28:33 AM »

500 or 550?

You certainly need to give them a complete clean.

I've just scored a set of 500F carbs on eBay (UK) for £26 so will post some pics when they arrive.
We can swap rebuild stories!

I bought these as a winter project as my 500 suffers from various carb-related maladies (flat spot, hesitation at idle and low speed/throttle etc). I plan a full refurb and to replace the carbs on the bike.

We shall see.

Good luck.

btripp · « **Reply #2 on:** November 03, 2005, 04:08:48 AM »

Steve,

The bike is a 550F and I think these are the origional carbs.

Yeah, I have another set from an earlier year, but I think these will clean up ok. Love to see those pics!

-Ben

MetalHead550 · « **Reply #3 on:** November 03, 2005, 05:48:10 AM »

Ewww! What kinda shape were the carb boots in...looks like they werent even on there. Should be a little easier reinstalling them with fresh carb boots instead of wrestling with dry, hard, 30 year old rubber.

M3JOC · « **Reply #4 on:** November 03, 2005, 08:54:28 AM »

Wrestling a 30 year old in rubber, Oh my, have i got the wrong end of the stick here.......

The carbs are in need of a very good clean up, but with time i`m sure they will be fine.
Rebuild kits available at $13 each carb from Z1 Enterprises, includes needle valve and seat, pilot jet, main jet, needle and circlip, top cover gasket and floatbowl o-ring.
Post a pic or two when there cleaned up.
Cheers,
Bob

btripp · « **Reply #5 on:** November 03, 2005, 06:14:42 PM »

Thanks guys!

I'm sure I'll need the new seals and everything.

The bike had sat for a very long time. I had the hardest time getting the carbs off. The boots were completely solid, with little to no give. I actually had to use a broomstick to *gently* pry them out. I pulled on them for maybe an hour. Wiggled, nothing worked. No amount of WD-40, not nothing. I actually had to cut three of the bands off, they were rusted so much. I even tried an impact screw driver with no luck!

If there's that much rust and deposits in the carbs, it's probably in the cylinder too wouldn't you think?

-Ben

pmpski_1 · « **Reply #6 on:** November 04, 2005, 12:08:36 AM »

That's a nice hound.

Is the rust just on the surface? I was wondering about the type of metal that carbs are made from and how deep the rust goes, or could go. Is it possilble for rust to get deep enough to pit the surface on carbs?

Tony CB750K6 · « **Reply #7 on:** November 04, 2005, 03:29:38 AM »

Hi Ben, tell me about carbs, I started fixing mine of the cb750k6, but one of them was too much corroded inside. So I bought a perfect used set of 4 for only $ 60,00 !
This saved me a lot of work, as my bike had not been used for 22 years ! See pics? Tony.

SteveD CB500F · « **Reply #8 on:** November 12, 2005, 11:48:25 AM »

As promised, here are the "before" pics of my eBay carbs

btripp · « **Reply #9 on:** November 12, 2005, 06:41:53 PM »

Man! Everybody's carbs look better than mine!!!!

I've got them ready to start. Got my carb cleaner and I'll probably start taking them apart tomorrow or Monday. I got busy moving stuff this weekend!

The boots were solid. I had to wedge the carbs off gently with a broom stick. There was no play whatsoever. I do have a new set and them seem somewhat softer. The PO just left her out in the rain for years. So sad.

-Ben

Einyodeler · « **Reply #10 on:** November 13, 2005, 02:45:12 AM »

Aaaaah carbs,you gotta love `em

btripp · « **Reply #11 on:** November 13, 2005, 04:18:30 AM »

Wow Stephan. Those cleaned up great! Did you replace the floats and all or just clean them?

-Ben

Einyodeler · « **Reply #12 on:** November 13, 2005, 05:49:43 AM »

All I replaced were the 0-rings and bowl gaskets , the rest came clean after much dipping , toothbrush scrubbing and compressed air.( I`ve never been a fan of aftermarket jets and needles,the adherance to Keihin tolerances is shabby at best.).

SteveD CB500F · « **Reply #13 on:** November 13, 2005, 07:41:44 AM »

I agree Stephan. I've decided to go with the gaskets and o-rings and clean the rest up to see what happens.

What's the best way of cleaning the carb bodies when they're all stripped down?
Bath in carb cleaner?
Blasting of some sort?

SteveD CB500F · « **Reply #14 on:** December 04, 2006, 07:26:45 AM »

Started the carb strip down last night. I know, I know, I said it was a "winter project" - I didn't say which winter!

The float bowls were full of crud but the jets came out easily. One of the throttle sliders was completely glued into the carb body and required loads of carb cleaner sprray to get it out.

Pictures to follow...

MadDogMcq · « **Reply #15 on:** December 04, 2006, 08:07:46 AM »

I used Carb & Choke Cleaner by Autocare on mine plus a soak in cellulose thinners (no plastic bits) and plenty of elbow grease with Solvol Autosol and a toothbrush. Another washout with carb-cleaner and dry-clean with compressed air.

SteveD CB500F · « **Reply #16 on:** December 04, 2006, 09:59:42 AM »

That's what I'm looking for. Talking to Bryan Jones last night and he uses cellulose thinners as well.

SteveD CB500F · « **Reply #17 on:** December 04, 2006, 11:28:11 AM »

The inside view.

Bodi · « **Reply #18 on:** December 04, 2006, 12:01:39 PM »

I couldn't get carb dip here (Toronto), Berrymans seems to be unheard of and Kleen-Flo was out of stock at Acklands.
So I looked at the MSDS for the stuff and it seems to be mostly methylene chloride. Paint remover is mostly methylene chloride... hmmmm... so I bought a tin of paint cleaner and mixed in a bit of lacquer thinner and acetone to thin it down a bit. Then I cludged up a slow rotating tumbler table to circulate the still-viscous goo around the parts in a clean paint can.
This worked quite well removing the crud and detritus from a set of nasty carbs (worse than the pics in this thread). Still needed a bit of toothbrush work (the soup dissolves toothbrushes rapidly so I learned to rinse the parts off before brushing!) and some solvol to shine up the bores and slide wells. The carbs look very nice, I don't have before pics but when I get enough time to finish assembly I'll try and post some "afters".
I left the felt choke rode seals in during soaking, then pulled them out when wet and soft to rinse them out using degreasing solvent and then soapy water followed with clear water; they ended up pretty clean and went back in easily. They are very hard to get out when dry and hard without a lot of damage.
I've been trying to polish the outsides a bit. The float bowls are easy but I've yet to find a way to polish the bodies with all the corners and crevices.
Tip: be careful with the choke plate screws. They have been punched on the back to lock them in their threads. You can probably get them out but you should probably get new replacements as the damaged leading threads don't much want to thread straight into the rod holes. Use some "small fastener" loctite on reassembly.

MadDogMcq · « **Reply #19 on:** December 04, 2006, 12:16:06 PM »

You know, with all this petrol and thinners and goodness knows what in my garage, I can only thank my lucky stars I packed in smoking!! I'd be a fireball by now

colb · « **Reply #20 on:** December 04, 2006, 12:46:17 PM »

Wait for the wife to go out and pop them in the Dishwasher, brings them up a treat.
But do rinse them well after to get rid of the salt content in the dishwasher

colin

medic09 · « **Reply #21 on:** December 04, 2006, 12:54:44 PM »

"cellulose thinners"

Somebody please tell me what that is, what it's for.

I've only cleaned carbs once (for my project Triumph, and the PO did most of the work with me helping), and I have to do mine this winter.

TomC · « **Reply #22 on:** December 04, 2006, 03:37:35 PM »

Hi Medic09
I believe that is lacquer thinner to those of us in North America. Soaked my jets in it.

csendker · « **Reply #23 on:** December 04, 2006, 04:33:36 PM »

627B's were stock on '71-'73 500's, not the 550F's.

Look at the FAQ --> http://www.sohc4.us/forums/index.php?topic=5410.msg26534#msg26534

550F's used 069A's. At least they're the same vintage (Keihin type 1's). Jets, needles, etc. are all different. Assuming the rest of your bike is reasonably stock, I would venture to guess that using the 069A's specs for jets, etc. would get you in the ballpark though.

News:

Author Topic: 627B Carb Rebuild Pics (Read 4282 times)

btripp

btripp

MetalHead550

M3JOC

btripp

Tony CB750K6

btripp

btripp