Wildguzzi.com
General Category => General Discussion => Topic started by: boatdetective on January 03, 2016, 09:42:10 PM
-
I have a niggling problem with my V50 not holding idle. When I say that I've replaced EVERYTHING from ignition, fuel, and air, I'm not kidding. I've done all my own work and am at wits end. Like my car- I would just like to wheel the bike in someplace and have a qualified mechanic diagnose and fix the problem (which, no doubt, is 98% diagnosis and 2% wrenching). My problem is that I've taken the bike to two people in the area so far and both experiences were nightmares.
Anyone here know a good, honest, mechanic in the Boston area?
-
I know this isn't what you're asking for but, the most common cause of an idle issue on DelOrto carbs are the choke plungers. They get hard and don't seal completely. If you've changed these already, I apologize.
-
I know this isn't what you're asking for but, the most common cause of an idle issue on DelOrto carbs are the choke plungers. They get hard and don't seal completely. If you've changed these already, I apologize.
Carbs have been rebuilt at least three times. Plungers changed out (though they did not need it). These plungers are brass.
-
Seacoast, about an hour away from you.
-
Have the inlet manifolds been off the heads? These are notorious for not sealing well.
Pete
-
Have the inlet manifolds been off the heads? These are notorious for not sealing well.
Pete
Thanks, Pete- yes, they've been off several times and the gaskets have been replaced at least once. The inlet rubbers were renewed a while ago. Still, I was considering doing the trick where you spray some volatile solvent on the inlet components to hear the engine rev as a check for inlet leaks.
Ignition (Dyna S) all checked, sensors replaced. Compression checked. Timing checked by rolling engine over by hand and checking voltage to each plug (does the plug actually fire when it should). plug wires were replaced (though they didn't need it). Coils Dyna replacements and seem to measure out fine.
I'm running out of things to throw away and replace....
JKK
-
Does it have a real choke or one of the enricher circuits? (my stab in dark)
-
Thanks, Pete- yes, they've been off several times and the gaskets have been replaced at least once. The inlet rubbers were renewed a while ago. Still, I was considering doing the trick where you spray some volatile solvent on the inlet components to hear the engine rev as a check for inlet leaks.
Ignition (Dyna S) all checked, sensors replaced. Compression checked. Timing checked by rolling engine over by hand and checking voltage to each plug (does the plug actually fire when it should). plug wires were replaced (though they didn't need it). Coils Dyna replacements and seem to measure out fine.
I'm running out of things to throw away and replace....
JKK
Is the advance unit operating freely? Have you ever checked the timing with a "timing gun"/stroboscope?
-
Ok, when you say, "not holding idle" do you mean.. won't idle, just dies.. or idle speed increases?
-
Ok, when you say, "not holding idle" do you mean.. won't idle, just dies.. or idle speed increases?
Starts up, runs fine through the range- let go of throttle and it just slows down and dies.
-
Can you hold a idle engine speed on the throttle? Perhaps the stops just need to be screwed a little further in?
-
Is the advance unit operating freely? Have you ever checked the timing with a "timing gun"/stroboscope?
Everything has been off, lubed, carefully installed.
As I recall (It's been a while), I rolled the flywheel over and checked the timing marks- I was very careful to check the marks against the valves opening and closing. For some reason, the advance marks did not seem to be in the right place. If I recall, normal engine rotation is clockwise when looking at the ignition on the front of the engine. I have the manual and read everything over.
The odd thing is that the problem first started suddenly after I rewired the ignition switch and installed a Tomaselli throttle. It was running great before hand. Throttle slack and all is fine. Ignition has been completely replaced to stock wiring.
Once again- engine starts up and seems to run fine- will not hold idle.
-
Can you hold a idle engine speed on the throttle? Perhaps the stops just need to be screwed a little further in?
Thanks- I believe I checked that- but it's worth checking. Basically, the motor should be able to run fine with the slides dropped fully with slack in the cable (of course, held open a crack by the idle screws).
-
Seacoast, about an hour away from you.
Great folks but they will not touch the earlier Guzzis... I first bought from them with the '04 EV, new then the '07 Norge, new. I happened to ask them if I could recommend them to owners of older Guzzis and they said, nope, we don't work on them.
Just an FYI...
Jonathan,
I too would think that inlet air is the culprit.
Best,
Rob
-
Your symptoms sure do point to extra air (leak in intake manifold ) between the carb and the head.
-
When it's about to die at idle, shoot a wee bit of starting fluid in a carb and see if it comes back. Same thing for any vacuum leak possibilities. Keep fire extinguisher handy! :shocked:
You might have multiple issues since it's been apart so many times.
-
Thanks- I believe I checked that- but it's worth checking. Basically, the motor should be able to run fine with the slides dropped fully with slack in the cable (of course, held open a crack by the idle screws).
I start with about 1 1/2 to 2 turns in on the stop screws.
-
Jonathan, the easiest way I know to search for air leaks is to have a can of starting fluid and when the bike begins to die, spray it around the intakes where an air leak could occur. If the idle picks up when it gets a shot of ether, you will be close to the trouble.
Reading through the above posts, I'm guessing that you are able to use the throttle to keep it running when it begins to die??? I'm also assuming you have performed a compression test?
Anyway, not exactly to your question, but an inexpensive easy way to look for a vacuum leak.
John Henry
-
you said carb rebuilt three times did you by any chance have the slides backward in carb body ,do a compression check ,look at valves too tight, pretty simple carb maybe something other than carb problem. good luck
-
you said carb rebuilt three times did you by any chance have the slides backward in carb body ,do a compression check ,look at valves too tight, pretty simple carb maybe something other than carb problem. good luck
The slides have a handy groove, so there's only one way to install them. Compression OK, Valves OK.
What gets me is that the problem first showed up after I did what would appear to be totally non related work. It was not a degenerative condition. The issue did not occur after I messed with the carbs. I had rebuilt carbs and replaced boots long before the issue occurred and they were(are) spotless.
-
Jonathon , you may be chasing your tail . Try a different direction than thinking carbs . My experience is that any intake leak that is small enough to allow the engine to run will result in an erratic idle , not a complete lack of ability to idle at all . Also doubt the issue is carb related . I would start with the changes made right before the trouble started .
Dusty
-
Great folks but they will not touch the earlier Guzzis... I first bought from them with the '04 EV, new then the '07 Norge, new. I happened to ask them if I could recommend them to owners of older Guzzis and they said, nope, we don't work on them.
Just an FYI...
Jonathan,
I too would think that inlet air is the culprit.
Best,
Rob
Interesting, in the past year while there for service, i saw a Mille GT (granted, not that old), and also a just serviced classic and well-ridden Eldorado waiting to be picked up. Maybe it depends on who you ask?
-
Jonathon , you may be chasing your tail . Try a different direction than thinking carbs . My experience is that any intake leak that is small enough to allow the engine to run will result in an erratic idle , not a complete lack of ability to idle at all . Also doubt the issue is carb related . I would start with the changes made right before the trouble started .
Dusty
[/quote
Dusty- I think you are correct. I really have been very careful with carbs and all. However- I've gone through the entire ignition system with equal care. As noted, the problem appeared after wiring up the ignition and installing a throttle. I've since reinstalled a new ignition switch. The throttle shouldn't have anything to do with it. Oh- when installing the throttle, I also installed a new kill switch. I don't know how that could affect things, though.
I'm flummoxed
-
(http://i115.photobucket.com/albums/n284/bcgilligan/Airhead%20Timing%20Window%20JPEG_zpsxoypfxmr.jpg) (http://s115.photobucket.com/user/bcgilligan/media/Airhead%20Timing%20Window%20JPEG_zpsxoypfxmr.jpg.html)
After 130,000 + miles on the R100GS, I decided to switch out the old 'beancan' ignition system. The timing advance had begun hanging up. These older electronic ignition systems still retained a mechanical bobweight and spring advance, even though the plugs were fired via Hall sensor, not points.
Got the new ignition system installed and tried to set timing with timing light. What I wanted was example "A" which is 6 BTDC at idle and 32 BTDC at full advance. Could not make that happen. If I got the idle set correctly as in example"B" (6 BTDC), then full advance was too far advanced (38 BTDC). If I got full advance set properly, as in example "C", idle was at about 0 BTDC, or not advanced at all.
Took it to a long time airhead wrench, who immediately said "the advance curve window in your new electronic ignition is too wide, and it isn't possible to set the timing correctly." We called the ignition supplier who indicated they had received a handful of modules loaded with the incorrect timing window, and he would immediately send the correct one to my home overnight.
The BMW mechanic felt it could be damaging to the engine to run it with more than the factory recommended full advance, so he set it at the correct high speed advance to get me home. At the same time, he said 'With no idle timing advance, I'm going to have to set your idle screws so the engine won't die every time you come to a stop. Just remember to reset the idle when you install the correct module, or you'll be idling at 1500-2000rpm."
Sorry for the lengthy story ..... but as I found, my brand new ignition module was the problem. And that an engine with little or no timing advance at idle simply won't idle unless the throttles are opened slightly more than normal.
Just another possibility.
-
(http://i115.photobucket.com/albums/n284/bcgilligan/Airhead%20Timing%20Window%20JPEG_zpsxoypfxmr.jpg) (http://s115.photobucket.com/user/bcgilligan/media/Airhead%20Timing%20Window%20JPEG_zpsxoypfxmr.jpg.html)
After 130,000 + miles on the R100GS, I decided to switch out the old 'beancan' ignition system. The timing advance had begun hanging up. These older electronic ignition systems still retained a mechanical bobweight and spring advance, even though the plugs were fired via Hall sensor, not points.
Got the new ignition system installed and tried to set timing with timing light. What I wanted was example "A" which is 6 BTDC at idle and 32 BTDC at full advance. Could not make that happen. If I got the idle set correctly as in example"B" (6 BTDC), then full advance was too far advanced (38 BTDC). If I got full advance set properly, as in example "C", idle was at about 0 BTDC, or not advanced at all.
Took it to a long time airhead wrench, who immediately said "the advance curve window in your new electronic ignition is too wide, and it isn't possible to set the timing correctly." We called the ignition supplier who indicated they had received a handful of modules loaded with the incorrect timing window, and he would immediately send the correct one to my home overnight.
The BMW mechanic felt it could be damaging to the engine to run it with more than the factory recommended full advance, so he set it at the correct high speed advance to get me home. At the same time, he said 'With no idle timing advance, I'm going to have to set your idle screws so the engine won't die every time you come to a stop. Just remember to reset the idle when you install the correct module, or you'll be idling at 1500-2000rpm."
Sorry for the lengthy story ..... but as I found, my brand new ignition module was the problem. And that an engine with little or no timing advance at idle simply won't idle unless the throttles are opened slightly more than normal.
Just another possibility.
Bob- Thx
I'm not quite sure what you mean by "window". I'm looking in the little timing hole at marks on the flywheel. I have a Dyna S and things had been running just fine. After much fettling, I realized that one of the sensors was not firing, so I ordered a new set of sensors. That did NOT fix the idle issue. I'm still not sure how to screw with the sensors to adjust timing- there is not much room for adjustment. Like I mentioned- lining up the marks on the flywheel in conjunction with the actual valves closing and piston confirmed at TDC has been frustrating. I've read the manual a thousand times and it's just not working.
Ultimately- I'd like to take it to a mechanic and have a fresh set of eyes look at it. My fear is that - like the past two "gurus" I've gone to, I will get a huge bill and the problem won't be fixed.
-
So, Jonathan.. where are the idle mixture screws set? Sounds to me that the idle mixture is just too lean. <shrug>
-
Adam Schoolsky of Rocketmoto recently opened his own shop on NH. He sells Motus, and restores/repairs vintage bikes. He's a Guzzi guy. Try him?
http://motusmotorcycle.com
-
Jon, 'window' was a poor choice of words on my part. A better choice would have been to say that my first new electronic module had too wide a range from idle to full advance. The range on my bike should be 26 degrees total, from idle at 6 degrees BTDC to 32 degrees BTDC at full advance. With the first new 'bad' module, the range was 32 degrees total. So, with the 'bad' module, if I set idle timing correctly, the full advance was 6 degrees too high (38BTDC.) Conversely if i set full advance correctly, idle advance was retarded by 6 degrees. On the Beemer, there is no way for me to set the idle and full advance timing independently of each other. Mess with one you mess with the other.
Your Guzzi sounds much more complicated to time than the BMW. Good luck .... sorry if I confused the issue.
-
+1 on Adam Schoolsky. LL 603-566-7619. Cell 603-566-4922. R3~