Clean Your Own Carb's - The Whole 9 Yards - by: Rick Massey

i got a 82 xj750 maxim and i want to soke the carbs is there ruber gaskets seals on the butter flys or is it safe to soke the carbs just take off the ruber parts i see and know about.do you thing soking is a must or spray carb cleaner is ok.thank you ivan.

 

Don't soak them until you have determined if the Cleaner will be harmful to Rubber Parts.

You'll have to get that information off the label of the Carb Cleaning Product.

 

rick the cleaner is harmful for plastic and rubber so should i just uer carb spray and prashuriset air.thay are in ok shape but the diafram cylinder things dont drop like a wet rag thay hazitat a litle. do you think i could clean tham up good with out soking tham i dont want to risk any rubber parts to go bad. thank you for ur reply.ivan

 

Don't soak them. Don't harm the butterfly shaft seals with dip-tank stuff.

I have a cleaning tank that lets me collect the carb cleaner from the spray cans. I dump the cleaner just sprayed-on to clean parts into a Paint Mixing Cup ... I let the crap settle and pour the cleaning fluid into a second Paint Mixing Cup which has a funnel lined with a clean COFFEE FILTER.

When the Carb Cleaner drains through the coffee filter into the second mixing cup ... I use that for "Pressure douching-out and cleaning"

 

thank you alot of great ideas ivan.

 

Re: Clean Your Own Carb's - The Whole 9 Yards - by: Rick Mas

So, finally got them back together - and installed 8) (bike didn´t start untill I thought of turning the petcock to prime .

Rick, as stated in another thread, your guide was an invaluable help. I wouldn´t have dared to try without it.

My experiences and suggestions:

"Cleaning Section": A warning not to expose o-rings, hoses and maybe plastic parts to carb-cleaner overnight, might be a good idea (I got a bit worried the next day, when I my mechanic told me horror stories of what carb-cleaner could do - knowing I had sprayed joint passages a.o. the day before).
The final cleaning of the carb bodies in the rack I made with carb-cleaner followed by spraying with mineral spirit from a brush-bottle, and then compressed air.

"Disassembling": After removing the first float bowl, I met a stuck screw in top/hat no. 2 - and turned out I had a couple more. Maybe it would be better to check for stuck top-hat screws before removing the floatbowls, it was a bit scary using an impact driver with exposed float-pin towers..

"Enrichment circuit": I found it difficult to understand the left/right orientation - and ended up with relying on my picture of the carb rack, taken from the engine side (this seemed most logical doing "choke" disassembling).

This also made it easy orientating the choke rod the right way, as the left side (from my working point of view) had the threaded hole for the lever-arm/cable pull bracket...(see pic 1)

Other than that it was just step-by-step timeconsuming fiddling with parts (another warning-suggestion: This work is best carried out in the winter (or if you absolutely have to to get the bike running) NOT when it´s 20C and sunny outside (the 3 days I spend doing carbs in the most perfect riding weather seemed VERY long .

"Reassembling" (including "Setting the float height": I cleaned everything and before assembling the float bowls I tried setting the float height to Service-manual specs: 16mm +/-1mm above gasket mating surface (see pic. 2).

This seemed pretty high (2-3mm increase necessary), as my fuel levels, measured with the carbs off-bike, levelled and with a hose were within specs, except maybe for one (which was my excuse for disassembling the carbs in the first place..).

And sure enough; apart from a rapidly rising fuel level, which soon went out of the drain-hoses (I had forgotten to do my postponed using-the-right-tool-holding-the-rack-steady-not-to-damage-the float-pin-tower- retightening 8) - the fuel level was 1-2mm low.

Back to the table, retighten! and setting the float height to 14mm (I twisted my brain a bit, and got help from the Factory-pro HP, to find out that a lower FLOAT HEIGHT (measured with the carbs upside down) would result in a higher FUEL LEVEL).

Also, I worked with the carbs almost level upside down but checked the height turning the rack, to where the floats starting to slip the float-needles - the difference was below 1mm...

Up with the carbs in my levelled setup, turning the petcock to prime - and while I was attending my coffee, I heard the unmistakenly gentle sound of gasoline hitting my cellar floor. Ups; shut off the gasoline and thought: "Now what"?

Emptied all float bowls and used the drain hoses to blow out the last excessive gas; turned out it was remains from my previous overflow..phew..

The following check showed the levels to be dead-on +/-½ a mm. YES!! (see pic. 3)

"Reinstalling the carbs": I reversed the "take the carbs off" method and used a piece of 1"x3" covering all 4 intakes to get the carbs in on the one side - then prevented that end from slipping out with a couple of stops between the airbox and my pry-bar pulled the other side in place. (see pic. 4 and 5). And yes, I remembered to tie up the throttle linkage before reinstalling!!

So, what can I say? The bike purrs like a kitten (all mixture srews out 3 turns) after a slight turn of the idle-screw. Can´t wait for tomorrows test-ride (and then, fabricating a YICS-tool for my borrowd Carbtune...Stay tuned 8)

Again, thanks for a great help, Rick - those mixture screws, springs, washers and o-rings sure are tiny, aren´t they

 

Re: Clean Your Own Carb's - The Whole 9 Yards - by: Rick Mas

Hey Finn.....okay, this is great info. I've always hated having to put the float bowls on, fill them up with gas, and measure with the drain tube before even beginning to set the float heigth, draining, taking apart, etc. What a convoluted, messy, time-wasting way of doing things...........

SO............this 14mm float heigth that you refer to....was this set using one of the Factory Pro float gauges (with the sliding arm), or if not, what are your measurement points for this 14mm dimension?

Although it's too late.....if you have a picture of that measurement that would be great!

And those are Hitachi carbs, correct? HSC33's??

 

Protect what you've done. Get a SMALL inline fuel filter working for you.

Tiny??? They look like Wristwatch parts!

Do they Clunk Test???

 

Re: Clean Your Own Carb's - The Whole 9 Yards - by: Rick Mas

I used a dial caliper and my measuring point was the farther end of the top of the float; aiming along the straight line of the top of the float, I rested the dial caliper´s "tip" on the edge of the carbhousing (the small one round the gasket in pic. 2). The yellow note-stickers provide a better background for equalling the dialcaliper-edge with the floats "top-line".

Didn´t take a picture, sorry - and yes, carbs are HSC33-11 Hitachi

 

´

Inline filter installed.


Clunk-tested fine - with a nice heavy clunky metal-sound they dropped resistance-free to the bottom - Actually I was surprised to see how clean the carbs were; apart from a little crud in to of the float-valve screens and in the enrichment valves, there wasn´t much dirt inside..

(except maybe for the "enrichment jets" in the float bowls - very hard to see, if they´re free from dirt. I tried sucking through them and they seemed to be clear - still haven´t tested the choke, though.

A side note: Checked my float needles/-valves by letting the carbs stay in the levelled setup with the petcock on prime overnight (passed!). When I checked fuel-levels before disassembling, 2 was leaking after ½ an hour..

A couple of more pics: A.o. a piece of rough nylon-carpet, used for cleaning surfaces, gasket areas etc.

 

I also cast a vote for you having one of the cleanest shop environments I've seen in awhile.

I can't even SEE the top of my bench, I have so many things going-on.

You could do Brain Surgery after you get those Float Heights done.

 

I bow humbly, Master, blushing with pride - but, seriously, after putting the carbs on the bike yesterday, I thought of taking a picture of my work-table, naming it "post-carb-chaos" (think I´ll do that tomorrow....

And before I take too much credit: The "Setup/levelled" pics were taken before disassembling the carbs - with a good clean-up as preperation (joked with a friend experienced in old SU-carbs that before approaching carbs a cleansing the surrondings and yourself-ritual would be appropiate, followed be placing the carbs on a clean cloth, lighting a candle and chanting a meditative "Aum" before getting to work 8)

 

is it just the picture or is your gas clear, colorless ?

 

It´s a bit yellowish..(not blue 8) (don´t know about your place but here in DK agriculture and others use non-taxed gasoline with a distinct blue colour..)

 

Re: Clean Your Own Carb's - The Whole 9 Yards - by: Rick Mas

Completed my carb cleaning project this weekend (pulled/cleaned/installed), using the wisdom gleaned from this thread. Every thing went smoothly, in fact, the hardest part was re-intalling the battery box!
After installing the carbs and a new set of NKGs, she started right up (with very little choke) and was idling free of choke after about 1 minute. This 750 Max has not been running in 2 months!
Took it for a spin under various speeds, and other than a possible high idle (feels like 1200 instead of 1100), this pike is purring!
Thanks go to Rick-o-Matic and Maxim and all who share here-

 

Believe it or not, you can still get the jets at your local yamaha shop. I replaced one of my 110 jets that way just this past week.

 

Re: Clean Your Own Carb's - The Whole 9 Yards - by: Rick Mas

Hey great info. thanks ! I am in the middle of doing battle with 3 pilot screws thats slots are stripped. screwdriver just ain't happenin' NO SIR. I'm fightin though. Just in case i lose . Would ya know whare i could get replacments ? Thanks, Rick

 

hey guys does any one have those pictures still? i have makuni carbs and those pictures would be a great thing for me to have.

 

I just finished overhauling a set of Mikuni's for a client.
I have a complete set of photographs of the cleaning, drilling-out, polishing bores and cleaning and polishing-up all the little stuff.

 

Rick are you going to post those. I would like to see if possible. Thanks