- Posts: 783
- Thank you received: 180
Fuel Overflow On My stock 77 KZ650 B1
- Forrest
- Topic Author
- Offline
- Sustaining Member
- The Mad Duck
KZ RIDER RELAY FLAG CARRIER #55
1977 KZ650B Ready & Fit to Roll Anywhere!
1974 F7 175 -first bike and still own, full resto soon!
2002 ZRX1200R -Red the faster color
2011 Concours 14 -Now a Snarling Wolf in Sheep's Clothing!
Please Log in or Create an account to join the conversation.
- Motor Head
- Offline
- User
- FIX UP YOUR BIKE RIGHT AND CHEAP
- Posts: 5138
- Thank you received: 391
Check to make sure the petcock will shut off first, from your description.
1982 KZ1000LTD K2 Vance & Hines 4-1 ACCEL COILS Added Vetter fairing & Bags. FOX Racing rear Shocks, Braced Swing-arm, Fork Brace, Progressive Fork Springs RT Gold Emulators, APE Valve Springs, 1166 Big Bore kit, RS34's, GPZ cams.
1980 KZ550LTD C1 Stock SOLD Miss it
1979 MAZDA RX7 in the works, 13B...
Please Log in or Create an account to join the conversation.
- martin_csr
- Offline
- User
- Posts: 8068
- Thank you received: 1656
Please Log in or Create an account to join the conversation.
- Forrest
- Topic Author
- Offline
- Sustaining Member
- The Mad Duck
- Posts: 783
- Thank you received: 180
Motorhead: I will disconnect my fuel line leading to the carbs prior to my filter and check to see if the petcock is leaking. I will then try your check with clear tubes as described. Very good tip and did not think of this. Petcock first!
Martin: The Petcock is a manual. The early KZs had these vs your, I assume CSR with a vaccum set up. I do agree that something must be interfering with a smooth turn of the petcock lever. It could be a form of corrosion or a build up. I am wondering if I overtightend the screw/s that hold the petcock lever, cover and O-Ring in place. I also was wondering if a shot of Slick 50 spray lube(PTFE-Teflon) would help. I am thinking of disassembling the petcock and trying to get right.
Here is a basic question on maunual petcocks to these (4) Mikuni VM24 SS carbs: If the fuel is allowed to flow freely to these carbs will fuel shut off at some point or simply continue to build and then flow out of the float bowl overflow tubes? I have been told by one or two experienced moto biz guys that the carbs should not allow the fuel to continue to flow out of the overflow tubes. I do not know the details at this time. I may research further and get back here. It has caused some confusion on my part. I can't wait to clear up any confusion and just get the bike to stop pissing on my garage floor!
KZ RIDER RELAY FLAG CARRIER #55
1977 KZ650B Ready & Fit to Roll Anywhere!
1974 F7 175 -first bike and still own, full resto soon!
2002 ZRX1200R -Red the faster color
2011 Concours 14 -Now a Snarling Wolf in Sheep's Clothing!
Please Log in or Create an account to join the conversation.
- Motor Head
- Offline
- User
- FIX UP YOUR BIKE RIGHT AND CHEAP
- Posts: 5138
- Thank you received: 391
1982 KZ1000LTD K2 Vance & Hines 4-1 ACCEL COILS Added Vetter fairing & Bags. FOX Racing rear Shocks, Braced Swing-arm, Fork Brace, Progressive Fork Springs RT Gold Emulators, APE Valve Springs, 1166 Big Bore kit, RS34's, GPZ cams.
1980 KZ550LTD C1 Stock SOLD Miss it
1979 MAZDA RX7 in the works, 13B...
Please Log in or Create an account to join the conversation.
- Forrest
- Topic Author
- Offline
- Sustaining Member
- The Mad Duck
- Posts: 783
- Thank you received: 180
ONE MORE BIT OF INFO, that I forgot til now. The fuel really started leaking right after I got my carbs synched. AND, right after this I took the bike for a weekend trip. On the return leg I went to switch from on to reserve. The petcock did not want to turn. I forced it over and up to reserve while riding. After this, I noticed fuel odor in the garage and then finally saw the fuel on the floor and the overflow tubes leaking fuel. Any feedback on this?
KZ RIDER RELAY FLAG CARRIER #55
1977 KZ650B Ready & Fit to Roll Anywhere!
1974 F7 175 -first bike and still own, full resto soon!
2002 ZRX1200R -Red the faster color
2011 Concours 14 -Now a Snarling Wolf in Sheep's Clothing!
Please Log in or Create an account to join the conversation.
- Motor Head
- Offline
- User
- FIX UP YOUR BIKE RIGHT AND CHEAP
- Posts: 5138
- Thank you received: 391
1982 KZ1000LTD K2 Vance & Hines 4-1 ACCEL COILS Added Vetter fairing & Bags. FOX Racing rear Shocks, Braced Swing-arm, Fork Brace, Progressive Fork Springs RT Gold Emulators, APE Valve Springs, 1166 Big Bore kit, RS34's, GPZ cams.
1980 KZ550LTD C1 Stock SOLD Miss it
1979 MAZDA RX7 in the works, 13B...
Please Log in or Create an account to join the conversation.
- Forrest
- Topic Author
- Offline
- Sustaining Member
- The Mad Duck
- Posts: 783
- Thank you received: 180
KZ RIDER RELAY FLAG CARRIER #55
1977 KZ650B Ready & Fit to Roll Anywhere!
1974 F7 175 -first bike and still own, full resto soon!
2002 ZRX1200R -Red the faster color
2011 Concours 14 -Now a Snarling Wolf in Sheep's Clothing!
Please Log in or Create an account to join the conversation.
- Patton
- Offline
- KZr Legend
- Posts: 18640
- Thank you received: 2098
If the petcock sediment bowl screen is damaged or missing, rust/grit from the gasoline can make its way to between the sliding mating surfaces inside the petcock.
The mating surfaces may become scratched and become difficult to turn and won't smoothly interface with each other when turning the petcock, and allow fuel to pass through the petcock even when in the OFF position (and also leak around the petcock lever).
The petcock's internal interface is cone shaped with the female part of the petcock case being metal (supposedly a smooth metal surface), and with the male part on the lever being a hard plastic-like substance.
I have tried without success to restore the scratched parts together by using valve grinding compound, and rubbing compound, and also with wet-dry sand paper, and then resorted to various other desperate measures, all of which were futile. Until a brand new petcock finally saved the day.
Good Fortune!
1973 Z1
KZ900 LTD
Please Log in or Create an account to join the conversation.
- martin_csr
- Offline
- User
- Posts: 8068
- Thank you received: 1656
Please Log in or Create an account to join the conversation.
- Forrest
- Topic Author
- Offline
- Sustaining Member
- The Mad Duck
- Posts: 783
- Thank you received: 180
Patton wrote: If the manual petcock is missing the screen filters that fit up inside the tank, or if the filters are torn or damaged, rust/grit from the gasoline is allowed to enter the petcock.
If the petcock sediment bowl screen is damaged or missing, rust/grit from the gasoline can to make its way between the sliding mating surfaces inside the petcock.
The mating surfaces may become scratched and become difficult to turn and won't smoothly interface with each other when turning the petcock, and allow fuel to pass through the petcock even when in the OFF position (and also leak around the petcock lever).
The petcock's internal interface is cone shaped with the female part of the petcock case being metal (supposedly a smooth metal surface), and with the male part on the lever being a hard plastic-like substance.
I have tried without success to restore the scratched parts together by using valve grinding compound, and rubbing compound, and also with wet-dry sand paper, and then resorted to various other desperate measures, all of which were futile. Until a brand new petcock finally saved the day.
Good Fortune!
Patton, You win the diagnosis prize! Thank you for your feedback here. I have finally exhausted my options: Rebuilt the carbs, and reassembled the stock 1977 B1 petcock. I am now convinced that Patton's expereience and summary is what has happened to me as well. The inner hard plastic drum of the petcok is somehow compromised. I do not see any surface imperfections. All I know is that the petcock leaks even in the OFF position.
What I need now is a new "NOS" petcock or a replacement for the stock 1977 B1 650 fuel tank. I hope someone knows of a source or has one. Please help! This KZ is really running great since the carb rebuild and synch. I just need to get the fuel to stop leaking. Please note that this is a 1977 with a ON/OFF/RESERVE lever position gravity fed petcock. The distance between the two screw/bolt holes is 1 3/4" Center to Center with the oval rubber O-Ring on the outside of these. I have all the dimensions if anyone is interested. It is a non vacuum diaphragm type but would consider a vacuum type or a pingle type if it would just bolt on or with a simple adaptor plate.
Help!!!!
KZ RIDER RELAY FLAG CARRIER #55
1977 KZ650B Ready & Fit to Roll Anywhere!
1974 F7 175 -first bike and still own, full resto soon!
2002 ZRX1200R -Red the faster color
2011 Concours 14 -Now a Snarling Wolf in Sheep's Clothing!
Please Log in or Create an account to join the conversation.
- 650ed
- Offline
- User
- Posts: 15344
- Thank you received: 2829
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
Please Log in or Create an account to join the conversation.