Hi All,
Today I wanted to do the first test run of my rebuilt 1973 Penton Hare Scrambler. At least that was the plan. I can't start the motor as there is no gas going into the float bowl, even when holding down the tickler. I am now trying to remove the float bowl to inspect the floats to see whether they are somehow stuck, but I can't get it off, not enough clearance between carburetor and engine case. The following picture shows the situation:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4087_zps97521fff.jpg)
1) Is there any obvious reason for gas flow blockage? Gas flows out of the supply line freely.
2) How do I get the float bowl off without disassembling the carburetor? Is there some must-know trick? I would think that one must have access to the jets without prior engine removal!
I had hoped for some two stroke sound but only got a gasoline bath!
Thanks for your input!
Andreas
Loosen the front and rear clamp and rotate the carb to remove the float bowl. The needle valve is probably stuck. Mike
Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
1975 Can Am 175 TNT & 77 250 Black Widow
1979 Husqvarna OR390
1976-78 RM & 77-79 PE Suzuki's
1974 CR250M 07 CR125R 79 CR250R
OK that worked. I could rotate the carb to remove bowl. I wiggled the needle a few times and the bowl fills up now. There seems to be only minimal clearance to move the float bowl out of the way though. In the process I broke the cork gasket (darn), Al can look forward to another order.
Even after kicking the engine over many times it won't start and I can't see any fuel on the spark plug. I don't think I am getting fuel into the cylinder. I will need to puzzle over this one for a little while I am afraid. Michael, thanks for your input, this certainly brought me forward.
Andreas
How certain are you of the float level? Does the carb over flow when you tickle it? Little things will cause big problems and give you proportionate headaches!
Good luck with it,
Dan McEntee
Starting a KTM engine usually requires holding down the tickler until fuel starts to dribble out of the overflow hoses, then I usually kick it over 2-3 revolutions slowly with the kill switch held down to keep it from kicking back, then one swift kick should get it to at least fire or even start. The colder the temp, the more they like fuel on start up. If you can't get any dribble out with the tickler, then you can lean the bike over until it dribbles out. Mike
Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
1975 Can Am 175 TNT & 77 250 Black Widow
1979 Husqvarna OR390
1976-78 RM & 77-79 PE Suzuki's
1974 CR250M 07 CR125R 79 CR250R
Yes, the carb does overflow when I hold down the tickler. I probably kicked it over some 50-times or more with throttle open or closed, pet cocks open or closed etc. When inspecting the spark plug I would have expected some gasoline on it but saw or smelled nothing on the plug. There is no audible trace of ignition. This leads me to believe that gas doesn't make it into the cylinder. But I will try your method, to be sure. Maybe Dan's hint at the fuel level in the bowl is the right track, I don't know.
I am riding a Norton (on the side so to day). Brit bikes usual start when you flood the bowl real well. So I tried that but to no effect. I am no stranger to swift kicks on the lever!
Thanks for your input, I really appreciate you help. I want to get this thing running now!
Andreas
I have heard that sometimes "others" :) will put a few drops of fuel into the engine down the spark plug hole. sounds a little shaky to me... But, from what I have heard, sometimes a balky machine will come to life....possibly this could be referred to as "manual fuel injection", but obviously I would never suggest this type of fuel-lish-ness...:D
Paul
I had a Hodaka Wombat that I built up by mixing and matching the best parts from two donor bikes, and went through the engine to replace bearing, seals, rings and such. When it came time to start, it fired a little bit on the first kick, then absolutely nothing, not even a pop over the next several days. Went through the ignition, checked and changed everything twice! I posted my troubles on the VINDURO list and Ed Chestnut responded with a similar story on a Wombat engine he built up from all new parts. Ed was the service manager for Hodaka back in the day, so you can imagine the fit that this put him in, Finally he decided to tow and bump start the bike, and had success. After that it started 1st or 2nd kick every time. I followed his advice and after towing it about 50 feet or so, it fired up and ran normally, and started 1st or 2nd kick every time after that! I was sure I was getting fuel through all of that, though. The dry plug makes me curious. Try Paul's advice of putting some premix down the spark plug hole, just a tea spoon or so, and see what happens.
Keep us posted,
Dan McEntee
I'll first remediate the cork gasket I broke (the carburetor is now leaking and I don't want to have a bonfire) and then try the "enriched mixture". I'll keep you guys posted when I manage to start the bike.
Thanks for your input!
Andreas
Andreas,
Use some gasket sealer on the float bowl gasket. That should eliminate the leakage at that site. Just to make sure, is the timing correct and are you getting spark at the plug? If either one of these do not exist, it will not start.
Tony
An all too common mistake is to leave a rag or wad of paper towel in the intake or exhaust port, that was originally intended to keep dirt/debris out of an newly rebuilt engine. I purchased a 78 RM400 this past summer from a individual who was moving and the engine had locked up after kicking it over several times before he was able to get it started after a top end rebuild by the famous engine builder/modifier Eric Gorr. The individual was sure the kick starter had locked up and didn't have the time to tear it down and fix it, so he sold it to me. Upon taking the head off, I found a black ankle sock that was in the exhaust port had worked its way partially into the cylinder and jammed the engine tight. It never hurts to double check! If it can't breathe, it can't pull in fuel. A plugged up exhaust pipe will do the same thing. Mike
Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
1975 Can Am 175 TNT & 77 250 Black Widow
1979 Husqvarna OR390
1976-78 RM & 77-79 PE Suzuki's
1974 CR250M 07 CR125R 79 CR250R
Yea, I already thought about this possibility but dismissed it based on: "no I wouldn't have done that..." If nothing else helps I will peek in there. I really hope to get the bike running over Thanksgiving. The last thing missing after that: painting of the tank.
Thanks for the brainstorming!
Andreas
Maybe not, but mice love introducing nuts and other items into pipes even hanging in the shop. Mike
Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
1975 Can Am 175 TNT & 77 250 Black Widow
1979 Husqvarna OR390
1976-78 RM & 77-79 PE Suzuki's
1974 CR250M 07 CR125R 79 CR250R
I took the carburetor off and looked into the engine by means of a small mirror and a lamp: nothing is stuck in the inlet or exhaust, at least as far as I can see. I replaced the gasket between the float bowl and the carburetor body. This is how the under side looks like:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4111_zps818fbc70.jpg)
I tested the level of the floats using the method described in the repair manual and found them to be correct. I probed the rear end of the exhaust with an elastic metal rod and found that I can put it in until reaching under the tank. The float needle moves freely. When taking out the holder of the float needle I found some hardened sealant that fell off. Does sealant belong there?
I put 1 ml of pre mix into the plug hole. The engine came to life for a few rotations of the crank but then died down, it wouldn't rev. I further see that the carburetor is leaking.
They only thing I see now is to replace the float needle with one with a rubber tip from Al. The one that is in my Bing 54 has a polished steel tip. It also seems very difficult to seal the fuel lines against the carb and the T-piece, connecting it to the two petcocks, even when using hose clamps (maybe Teflon tape would help). Maybe I need to gain access the front end of the exhaust and probe it with a wire to assure that its free of stuff.
This seems a difficult problem to solve! I had hoped for a Thanksgiving weekend test run but it probably ain't gona happen.
Cheers
Andreas
Andreas,
When you pull the carb off is there much fuel in the bowl? Is the carb leaking out the overflow or just leaking from ???
I realize you set the float in the way that you feel is proper, but I wonder if it is correct, no offense intended, just trying to help.
With the carb off the bike and the float bowl removed. With the carb upside down and level, if you blow into the fuel line and slowly lift the float upward from its resting position, does air start to flow thru the fuel line when the float becomes level, if not when does it start to flow?
Paul
Hi Paul,
Thanks for the input! Fuel isn't leaking from the overflow. I have a tube on it. When the bowl fills up, fuel is starting to accumulate under the carb. I can't exactly identify where it is coming from. It might be leaking due to a bad fit of the fuel line. I will try Teflon tape to see whether this helps. It could be overflowing somewhere, thus, my question about the float needle.
I did set the floats according to the manual, asking to put the carb on a level surface and make sure the floats are level when touching the needle. I haven't tried the "blow in method" yet as I didn't know about this. Sounds reasonable but now the carb is back on. The tickler came apart (the pin fell out) so I will have to take the bowl off again to fix this.
I appreciate your advise
Andreas
Where is the copper siphon tube that should be in the carb body? Good Luck! Harry
There is a small tube attached to the bowl. Is that what you mean? According to pics on Al Buehner's web page this is where it should be for a 36 mm Big carburetor.
Thanks for helping brain storm on this!
Andreas
On my set up the tube is fixed to the carb body. I believe it serves to siphon gas from the carb bowl. At the end of the tube (in the bowl housing) is a small hole. Make sure this is not plugged. Harry
Hi All,
After some testing I excluded some possible problems brought up by some in earlier posts and identified one issue.
1) There were no rags in either the intake or exhaust port.
2) I made the exhaust accessible and used a plumbing implement to probe its inside. See the photo:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4120_zps3ffee414.jpg)
I could insert the thing until it hit the area were the end pipe attaches. Perhaps there is some baffle or something there. Probing and rotating the device brought not organic matter (nuts some nest or stuff like that)to light.
I then fashioned a "gas attachment" allowing me to blow into the exhaust:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4123_zpsfd31117c.jpg)
I could blow through the pipe. Opening the spark arrestor at the end did not lead to a perceptible increase of flow impedance.
From these observations I would conclude that the exhaust is not blocked.
3) I took the carburetor off again and tried Paul's "blow in" test to re-check the float level. Whenever the floats becomes horizontal (with the carb mounted on a level surface) I can feel the float needle closing. The floats need to press a little further down until the needle closes fully. I conclude that the float level is OK. I then put the float bowl back on and filled the carb with gasoline, using a syringe:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4130_zpsdcb53581.jpg)
I could fit 40 ml of gas into the carb until the needle closes. Is this a reasonable fuel volume in the bowl to allow reliable operation?
Continuing to fill the tube in 5 ml gasoline increments showed that they would slowly seep into the bowl at a rate of about 0.8 ml/min. This continued until I had filled in another 22 ml of gasoline into the bowl. At that point the bowl overflowed through the little brass tube attached to the bowl. This shows that the float needle doesn't properly seal. Now comes the issue: Al Buehner's web site lists a 7 mm triangularly shaped float needle while mine has 6 mm and has a four point shape. Would anybody know where I could get a rubber or Viton tipped replacement from?
And one more important point: am I missing a tube attached to the carb as Harry pointed out? The parts list isn't clear so I have no way of determining how the carb should look like. Could someone perhaps post a photo of a complete and working carb's underside? Mine is a Bing 54, type 2, 36 mm, ID 102.
Thanks for your input!
Andreas
Get a real carb, and have that one dipped in bronze and send it to a museum......
1976 MC 5 Original Owner
1982 Suzuki PE 175
1976 Penton 175 GS
1976 Penton 250 GS
Hi Andreas...If you could post a picture of the bowl that would help me to explain or at least know if I'm on the right track. I'd post pictures if only I knew how! Harry
Here a picture of the underside of my Bing 54:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4127_zps2d956787.jpg)
Is some component missing e.g. some pipe?
Here a picture of the filled float bowl. The little brass tube is the overflow. Once the liquid reaches this level it drains through the tube out of the bottom.
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4126_zps20667df3.jpg)
To post an image you need to host them on a web site like e.g. Photobucket (a free service):
1) In your POG posting click on the "Insert Image" icon. This will insert #91; img #93; #91; /img #93; into your post.
2) Post your image to Photobucket.
3) While in Photobucket, click on the image you want to post.
4) To the right of the picture you selected will be a list of options. Left-click on "Direct". This will put the appropriate URL into your buffer.
5) Go back to your POG post and insert the URL by right-clicking and then pasting the URL of your image between the #91; img #93; #91; /img #93; command. The picture will now show up directly in your post. You need to either preview or post the text to see the result.
Cheers
Andreas
P.S.: I am sorry for the #91 and #93 statements. This HTML code for "[" and "]", respectively. It renders correctly in "Preview" mode. However, the web site modifies the text when posting and the HTML symbols aren't rendered correctly any more. This is probably an issue with some optimization this web page tries to perform. The procedure is correct.
I hope I didn't get your hopes up. My 24mm includes a brass tube that is fixed in the body that fits into that cast hole in the bowl when assembled. There is a small hole (also shown in your picture) at the bottom of the casting that must be clear... at least on the 24mm. Check that this is clear with a fine wire or drill bit. Harry
Hey Andreas, I know this has already been mentioned, but you may not be letting enough fuel overflow and run down into the intake passages to fire the motor. I have a 74 175 KTM Jackpiner, and it does not have a choke, as I noticed yours doesn't either. Anyway, to start that motor, I have to let the carb overflow by holding the tickler until a puddle forms on top of the cases, under the carb. While the fuel is dripping out the overflow tube (in the bottom of the bowl), fuel is also running down inside the intake passages. Even then it takes a couple of kicks, and when it does fire, I have to keep it running by using the throttle. Once warmed up, it screams and idles like a kitten. I will then take a rag and soak the excess off the cases. The 175's that have chokes do not require the puddle of gas under the carb, maybe just a tad if bike was completely run out of fuel, meaning no residual in the crankcase.
Second, be sure you have spark from the motoplat, if you still have one.
Keith Meatyard
Thanks Keith! I will first have to fix the float needle. As it's not sealing properly any more whenever I use the tickler the carb just keeps overflowing. I'll try your technique once the carb is back on.
Cheers
Andreas
I used to have a MC5 250 and the starting ritual was as Keith described, plus, I would have the front wheel lower than the rear if possible. Also, once it fired, I would just hit the tickler to keep it running when it tried to die out. Awesome running machine, and easy to start once the "ritual" was preformed.
On the first morning of the 1973 ISDT, when it was time to start my Sachs powered 125cc Penton I kicked and kicked, with no results. Erwin Leichner (sp) from KTM who was on the start line with us, ran over and indicted to me to flood the engine with the tickler, which I did, and it fired on the next kick. :D First morning jitters.....
Paul
Hi All,
I should, at this point, change the subject line of this post to "too much gas". I have a little Bing mystery for this group. My 36 mm Bing 54 carburetor (2/36/102) has a leaky float needle, as described in previous posts. So I purchased a new one from Bing USA. The next image shows a comparison of what I got (left) to what was in the carburetor (right):
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4139_zpsd67b6aff.jpg)
These components seem to have no similarity. The original Bing part needs to be pressed into the carb body while the holder, I found installed, is screwed in (by means of a 10 mm thread). The following image shows the carb body with the threaded bore accepting the float needle holder:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4142_zpsd88728a3.jpg)
The last image shows the float needle installed in the carb. The little clip on there prevents the needle from falling out. However, the is no connection to the floats other than them pressing via the tap on the spring loaded stem. The float needle I found in there has a quadratic rather than triangular cross section.
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4111_zoomed_zpsc975a87c.jpg)
Has anybody in this group ever seen such a setup? The Bing people cannot identify this. Or could this just be some odd modification done by a previous owner, using a non-Bing part? Can anybody identify the needle holder I have?
Thanks for your input
Andreas
That is a Mikuni float needle/valve. You can stay with a Bing, but you need to get rid of that one and get a new one, or better yet, get a Mikuni.
Brian
Hi Brian,
Thanks for ID-ing the needle. Replacing the existing part with the appropriate Bing component won't be easy though. The existing threaded bore in the carb body is larger than the Bing needle holder. I will have to fashion some kind of sleeve accepting the holder that engages the thread. I will need to understand whether there is enough room for that.
Thanks for the input!
Andreas
I would just get another carb, that one is never going to work right. If you stick with that one, use another Mikuni needle/seat trying to make the Bing part work when its already been modified for the Mikuni part is pointless.
Brian
This took a while! To fix the problem with my float needle (a Mikuni needle in a Bing carburetor) the people from the Bing Agency build a new float needle seat and installed it in my carburetor body. Here a photo of the new modified assembly:
(http://i1341.photobucket.com/albums/o746/andreas_g_piepke/Penton/100_4146_zps1bdffcc0.jpg)
Now I can install a Viton tipped Bing float needle. I just tried this out on the bench and found the needle to seal properly. I adjusted the floats to be vertical when resting on the needle, which translates into about 40 ml of gas in the float bowl.
Andreas
Andreas,
Have you check to see if the gas is running freely through the gas lines without being attached to the carb? I once had a case of my gas cap on the tank being too tight, and not allowed proper venting, so the gas would not flow through the gas lines.... Also, how good are your petcocks? They too might be restricting the fuel flow....
1976 MC 5 Original Owner
1982 Suzuki PE 175
1976 Penton 175 XC
Thanks fot the input. The gas lines are free and there is sufficient flow. Both petcocks are new. I checked flow by draining the tank content through the fuel lines.
I think the fuel problem is solved now. I even managed to start the engine, probably for the first time in decades. In the process I discovered two new problems I need to fix:
1) The clutch doesn't separate. I will remove the clutch cover for inspection.
2) The engine sems to rev extremely "tired". I'll re-check ignitin timing and compression. What pressure should a rebuilt 250 ccm engine (1973 vintage) deliver?
The cylinder has been bored, new piston, connecting rod and bearings installed. The engine should run well once it's propely set up.
Cheers
Andreas
Compression should be 160 to 180 with new bore and piston. Might be a jetting issue. Sounds lean.
73 Jackpiner
73 Husky 360 WR/RT
76 Husky WR360
78 husky cr250
10 ktm 250xc
02 bmw r1150r
Thread hijack.
Pulled up this thread searching for petcock answers (the best way to replace, least expensive, etc.) and found this post showing everything one needs to know, pictures included, about a Bing 54.
Thanks for all of the detail, advise to owners, and clear photographs.
RP