Author Topic: Air -box problem  (Read 4373 times)

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Offline gsb

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Air -box problem
« on: October 29, 2012, 11:35:13 PM »
Hi !
I,m building up my K2 with F1 750 motor.Holders for air box are completly rusted and i make new from stanliess stell .Problem is how to disasembly uper part from air -box .there are 2 screws (long ) with distance nut  .I can,t figure out how to disasemble this ?
Thanks !  gsb

bollingball

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Re: Air -box problem
« Reply #1 on: October 30, 2012, 04:41:30 AM »
I'm not sure what box you have. Got a picture? If is like mine the nut on the bottom might be spinning in the plastic. Problem is you cannot get a socket on it so you may have to hog out around it. I had to do this then when I got it apart cleaned up I epoxied it back in. Now I keep anti seize on those long bolts after filter change.
Ken
« Last Edit: October 30, 2012, 04:11:11 PM by bollingball »

bollingball

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Re: Air -box problem
« Reply #2 on: October 30, 2012, 04:12:33 PM »
GSB I got the photo wrong the first time
Ken

Offline gsb

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Re: Air -box problem
« Reply #3 on: October 30, 2012, 11:27:42 PM »
 Hi !
I was thinking about screw on the top of air box on the holder ,thats my problem  -it come together with screw on your picture
gsb

bollingball

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Re: Air -box problem
« Reply #4 on: October 31, 2012, 04:32:16 AM »
That hex nut is on the bottom. On the other side top of the box you will see another one it is on that little L shaped bracket. Those two hold the two halves together. I thought that was what you were trying to do. Can you post a picture of the one you are talking about. Put your wrench on the top one and while turning it look at the bottom and see if it is turning.
Ken

Offline madmtnmotors

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Re: Air -box problem
« Reply #5 on: October 31, 2012, 04:42:55 AM »
Hi !
I was thinking about screw on the top of air box on the holder ,thats my problem  -it come together with screw on your picture
gsb

    Do you have the bottom half removed? If so, are you now trying to further disassemble the upper half so that you can replace the brackets? If so, then I can probably help you out with pictures of how the upper half is further disassembled. The center divider is held by threaded collars that are on the long upper bolts. I had to hold these with vise grips as I loosened the bolt, but you may have to tap them free as they tend to get jammed onto the upper shoulder of this upper bolt. I can post a pictorial sequence if necessary, I've got a couple airboxes completely disassembled right now for similar refurbishment (one needs a gasket, the other needed the brackets painted). Let me know, it might take a day or two, I'm scrambling to get a project back together as well.
TAMTF...


Wilbur



Projects:
"Evolution": http://forums.sohc4.net/index.php?topic=100352.0
"P.O. Debacle": http://forums.sohc4.net/index.php/topic,126692.msg1441661.html#msg1441661
F2/F3 O-rings: http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721
Cam Tower Studs: https://www.mcmaster.com/#93210a017/=t19sgp
Clean up that nasty harness: http://forums.sohc4.net/index.php?topic=137351.msg1549191#msg1549191
http://forums.sohc4.net/index.php/topic,148188.msg1688494.html#msg1688494
http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                          
Charging system diagnosis: http://forums.sohc4.net/index.php?topic=1012.msg8345#msg8345
Get the manuals: http://manuals.sohc4.net/cb750k/
The Dragon: http://forums.sohc4.net/index.php?topic=45183.msg1571675#msg1571675
Headlight Switch: http://forums.sohc4.net/index.php?topic=113986.msg1283236#msg1283236
Branden's leak free top end thread: http://forums.sohc4.net/index.php?topic=107040.0
Engine Lifting Made Easy: http://forums.sohc4.net/index.php/topic,58210.msg1684742.html#msg1684742
                                      http://forums.sohc4.net/index.php/topic,100352.msg1675840.html#msg1675840
Static and Dynamic Timing: http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Airbox Gasket Replacement: http://forums.sohc4.net/index.php/topic,114485.msg1290000.html#msg1290000
"Café" : http://forums.sohc4.net/index.php/topic,84697.msg953814.html#msg953814
PD Carb Choke Linkage: http://forums.sohc4.net/index.php/topic,100352.msg1669248.html#msg1669248
                                    http://forums.sohc4.net/index.php/topic,110931.msg1248354.html#msg1248354
                                    http://forums.sohc4.net/index.php/topic,48858.msg515204.html#msg515204
Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
Taiwanese Cam Chain Tensioners:  http://forums.sohc4.net/index.php/topic,155043.msg1774841.html#msg1774841
Gumtwo Seat Cover: http://forums.sohc4.net/index.php/topic,164440.msg1897366.html#msg1897366
Primary Drive: http://forums.sohc4.net/index.php/topic,166063.msg1919278.html#msg1919278
Tank Latch: http://forums.sohc4.net/index.php/topic,165975.msg1919495.html#msg1919495
Shorten your forks: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html DO NOT CUT THE SPRINGS!
Clutch How To: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html
Late model K7/K8/F2/F3 front sprocket cover removal: http://forums.sohc4.net/index.php/topic,178428.msg2072279.html#msg2072279
630 to 530 conversion: http://forums.sohc4.net/index.php/topic,180710.msg2094423.html#msg2094423

Sent from my Tandy TRS-80!

Offline gsb

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Re: Air -box problem
« Reply #6 on: October 31, 2012, 11:14:13 AM »
 Hi !
yes thats the problem -how to diasemble uper case .Some pictures were nice .I posted some pictures of new holders -my father  made me new from stanliess stell .
gsb

Offline madmtnmotors

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Re: Air -box problem
« Reply #7 on: October 31, 2012, 06:26:43 PM »
Okay, here goes:

From your description you are looking at something like this:



And these are the tripping point. Notice the untreaded portion of the bolt:



You are going to want to support the bracket, the bolt must be able to move freely. I used an oversize socket (12mm or 14mm deepwell):



Use a block of wood on the end of the bolt to protect the threads. Strike sharply, BUT NOT TOO HARD! The airbox is plastic, start easy and strike a little harder until the retainer moves. Did I mention DON'T OVERDO IT:



You are trying to get the retaining nut(?) to move up the unthreaded portion of the bolt. This retainer is threaded, but over time it gets jammed on the shoulder of the bolt (as we will see in a following picture). My guess is that ham-fisted tightening of these bolts jams this retainer onto the shoulder of the bolt:



Once the retainer moves, then you can unscrew the retainer from the bolt. The retainer nut(?) is threaded, and you will likely need to grasp it with vise grips. ONLY TIGHT ENOUGH TO HOLD IT! Too tight and you might crush/distort the retainer nut(?) making it even more difficult to remove:



Here's a close up of the freed retainer nut(?). Notice the little wrap of loose thread that was a result of the retainer being jammed against the shoulder of the bolt. You can see the shoulder on the bolt in this picture:


Assembly is similar to the reverse of disassembly (except for the hammering part!).

Easy-peasy
« Last Edit: November 01, 2012, 09:36:38 AM by madmtnmotors »
TAMTF...


Wilbur



Projects:
"Evolution": http://forums.sohc4.net/index.php?topic=100352.0
"P.O. Debacle": http://forums.sohc4.net/index.php/topic,126692.msg1441661.html#msg1441661
F2/F3 O-rings: http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721
Cam Tower Studs: https://www.mcmaster.com/#93210a017/=t19sgp
Clean up that nasty harness: http://forums.sohc4.net/index.php?topic=137351.msg1549191#msg1549191
http://forums.sohc4.net/index.php/topic,148188.msg1688494.html#msg1688494
http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                          
Charging system diagnosis: http://forums.sohc4.net/index.php?topic=1012.msg8345#msg8345
Get the manuals: http://manuals.sohc4.net/cb750k/
The Dragon: http://forums.sohc4.net/index.php?topic=45183.msg1571675#msg1571675
Headlight Switch: http://forums.sohc4.net/index.php?topic=113986.msg1283236#msg1283236
Branden's leak free top end thread: http://forums.sohc4.net/index.php?topic=107040.0
Engine Lifting Made Easy: http://forums.sohc4.net/index.php/topic,58210.msg1684742.html#msg1684742
                                      http://forums.sohc4.net/index.php/topic,100352.msg1675840.html#msg1675840
Static and Dynamic Timing: http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Airbox Gasket Replacement: http://forums.sohc4.net/index.php/topic,114485.msg1290000.html#msg1290000
"Café" : http://forums.sohc4.net/index.php/topic,84697.msg953814.html#msg953814
PD Carb Choke Linkage: http://forums.sohc4.net/index.php/topic,100352.msg1669248.html#msg1669248
                                    http://forums.sohc4.net/index.php/topic,110931.msg1248354.html#msg1248354
                                    http://forums.sohc4.net/index.php/topic,48858.msg515204.html#msg515204
Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
Taiwanese Cam Chain Tensioners:  http://forums.sohc4.net/index.php/topic,155043.msg1774841.html#msg1774841
Gumtwo Seat Cover: http://forums.sohc4.net/index.php/topic,164440.msg1897366.html#msg1897366
Primary Drive: http://forums.sohc4.net/index.php/topic,166063.msg1919278.html#msg1919278
Tank Latch: http://forums.sohc4.net/index.php/topic,165975.msg1919495.html#msg1919495
Shorten your forks: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html DO NOT CUT THE SPRINGS!
Clutch How To: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html
Late model K7/K8/F2/F3 front sprocket cover removal: http://forums.sohc4.net/index.php/topic,178428.msg2072279.html#msg2072279
630 to 530 conversion: http://forums.sohc4.net/index.php/topic,180710.msg2094423.html#msg2094423

Sent from my Tandy TRS-80!

Offline gsb

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Re: Air -box problem
« Reply #8 on: November 01, 2012, 09:20:43 AM »
Hi  Madmtnmotors !
Thanks for pictures , it,s my first bike an I dont figure out how to dissasembling uper part of air box . I will make some pictures of new holders when i finished .
gsb

Offline Tugboat

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Re: Air -box problem
« Reply #9 on: November 01, 2012, 09:44:30 AM »
^What he said. This is how I did it when I had the same problem. Good luck!
If it's worth doing, it's worth doing twice.

Offline NewOldSchool

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Re: Air -box problem
« Reply #10 on: November 01, 2012, 10:29:33 AM »
I'm not sure what box you have. Got a picture? If is like mine the nut on the bottom might be spinning in the plastic. Problem is you cannot get a socket on it so you may have to hog out around it. I had to do this then when I got it apart cleaned up I epoxied it back in. Now I keep anti seize on those long bolts after filter change.
Ken

You don't have to bore the crap out of the plastic like that, you could always take a rotary tool and cut a groove in each bolt for a flat headed screw driver. That's what I did.
Not putting miles on your bike is like not having sex with your Girl Friend so she'll be more desirable to her next Boy Friend.

Offline lucky

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Re: Air -box problem
« Reply #11 on: November 01, 2012, 02:54:02 PM »
A very common problem.

bollingball

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Re: Air -box problem
« Reply #12 on: November 01, 2012, 05:58:27 PM »
I'm not sure what box you have. Got a picture? If is like mine the nut on the bottom might be spinning in the plastic. Problem is you cannot get a socket on it so you may have to hog out around it. I had to do this then when I got it apart cleaned up I epoxied it back in. Now I keep anti seize on those long bolts after filter change.
Ken

You don't have to bore the crap out of the plastic like that, you could always take a rotary tool and cut a groove in each bolt for a flat headed screw driver. That's what I did.
Now you tell me ;D I all ready had the epoxy out to repair a couple of holes from a PO But thanks
Ken

Offline Erny

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Re: Air -box problem
« Reply #13 on: May 08, 2018, 01:55:00 PM »
great to find this thread! Had eaxctly the same problem today  :D
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