Author Topic: Check those breather hoses-Oil tank overflow problem  (Read 876 times)

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Offline ekpent

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Check those breather hoses-Oil tank overflow problem
« on: March 30, 2017, 08:33:35 AM »
 Mainly putting this out there in case someone else has a problem someday. Put my second 750 basketcase bike project Blackie back together this winter and poor member Sean B was the first to take it out for its inaugural  ride in many years recently since he was visiting that day at the shop. This bike had ate its cam and the engine was out and partially torn down when I got it several years ago. Well it ran well but when he returned the rear of the bike was covered and dripping with oil. OH OH did I break a ring or two or was a hose plugged Hmmmm. Had a little time yesterday and pulled the gas tank and breather hose off the valve cover and shot some brake cleaner in there.Had a cat food can to catch the drippings and 'nuttin honey'. Put a wire in the hose and felt resistence-Hmm this might be a good thing. Filled the hose again, mounted an air gun to the hose and gently pulled the trigger and was amazed at the amount of 'plugs' that came out of the tube. At least 5 major round oblong plugs and much other material. Pictures shows some of what was recovered. Mercy those Mud Daubers or whatever are nasty little things. Had seen some signs of them around the carbs and other spots on the bike when working on it but just forgot to blow the tube out before putting in the engine. She had a rough first 3 miles  ;D  Lesson learned-check it all !!
  Bike is running very good, now what to do next-2 stroke or 4  hmmm
« Last Edit: March 30, 2017, 08:39:38 AM by ekpent »

Offline Johnie

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #1 on: March 30, 2017, 08:36:04 AM »
Nice reminder Eric! Great looking bike and very nice job.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline PeWe

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #2 on: March 30, 2017, 09:09:40 AM »
Congratulation! Bike is back to where it belongs...on the road.
Was it insects that had moved into the hose? You'll plug the hose next winter or you do not have those in you garage?
That hose should be replaced on my bike. Could not find a slim 12mm or 1/2" hose as Honda used, only thick oil/hot water hose whcih has very thick OD.
Original on my bike was over 1m long, from valve cover to right rear passenger footpeg.

EDIT: You have several bikes in your garage, right? I think I saw something like a Z1-900..?
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline ekpent

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #3 on: March 30, 2017, 09:17:36 AM »
 I have never seen those type of wasps around my house or shop before PeWe if that was what caused it. I bought the bike on the day before Christmas (Dad needed money for gifts)at least 3 or 4 years ago about 50  miles north of where I live here in Michigan out out of a basement. Having owned a 750 or multiples since 1981 I have never seen that hose get plugged before,especially as bad as this one was. When I tore down the engine one cylinder had 'food' inside from when the PO must of had a spark plug left out, maybe from the same insect ?? Since its seeds probably a mouse depository.
« Last Edit: March 30, 2017, 09:57:08 AM by ekpent »

Offline Ridem32

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #4 on: March 30, 2017, 09:31:48 AM »
Here in Mississippi we call them dirt dobbers. They will fill up every hole known to man with that hard type dirt. Many many weed eaters want run after sitting all winter always check the muffler those dirt dobbers will fill up a weedeaters exhaust.


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Offline seanbarney41

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #5 on: March 30, 2017, 09:36:51 AM »
You take it out for another blast yet Eric?
If it works good, it looks good...

Offline ekpent

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #6 on: March 30, 2017, 09:41:58 AM »
You take it out for another blast yet Eric?
Yep took it out yesterday for a good shakedown and put some more oil in it. Its a little over the full line now and staying in the tank.  I will call you when I need a test pilot again- if you dare   ;D ;D

Offline Johnie

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Re: Check those breather hoses-Oil tank overflow problem
« Reply #7 on: March 30, 2017, 09:44:33 AM »
I get those mud cocoons so to speak from the local hornets around here. Find them attached to the particle board in the garage.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA