moisture= no spark, any ideas?

[dj52l]

Any ideas would be welcome. I bought "88 Vmax late lat Summer and owner warned that she would take 20 minutes to dry out after washing. It is getting worse and I can't find a fix. Last washing took 4 days (humid conditions) in shed.
When the bike starts, it fires on first crank and runs great. The last 3 weeks, it won't even start on slightly humid mornings, 75 degree, (no washing) sitting in gravel floored shed. Leave it alone for 3-4 hours , it fires right up..90 degree weather mid day by then, too hot to start out on a ride.
Previous owner bypassed the kickstand switch somehow, and added some lights which work fine, I have cleaned the only moisture I can find, a bit of oil around the kickstand , and blown everything off and checked connections. The rear coils are dry as a bone.
I have tried to get to the front coil and black box, but darned if I can get the air box base off. I remove the three screws I see holding it and it won't lift off. The online service manuals are no help. I assume it has to come off to get to the CDI plugs??? I have read that the plugs may need cleaning and electrical grease applied.
How do I get to the black box ? Luckily, the bike has never quit on me once it starts, but I'm afraid to ride anywhere if there is rain in the Midwest and my vacation is fast being used up when the Vmax won't start each and every morning.
Anybody got any ideas? Or a bid from someone in Arizona for a nice looking "88 Vmax ? Thanks!

 

[[email protected]]

To take the airbox off you have to loosen the 4 clamps that secure the rubber boots to the top of the carbs. They are more easily seen if you remove the chrome "H shaped" intake manifold covers. Then you have to remove the breather tube from the bottom of the airbox. The breather tube is easiest to see with the coolant overflow bottle removed. Take the lid off and then pull it right up and out. Note that the carb boots seal on there TIGHT sometimes. Not sure what 3 screws you're talking about. If you mean the three on the inside of the airbox in between the intake runners that will not help in removal, they can stay in place.

 

[jfeagins]

I've seen where a weak battery will crank fine, but starve the cdi box of enough juice so that it won't spark easily. You might try jump starting the next time it won't fire to see if that makes a difference at all. If it does, you might need to go through the charging system and/or battery to improve voltage.

If washing or getting it directly wet were the only symptom you had, I'd say you need to address the fitness of the plug wires and boots. When that happens, you could maybe spray WD40 in them to remove the moisture to get the bike going.

 

[dj52l]

Thanks, that makes sense...I'm a fumble fingers and none of the on line manuals had instructions.
I have read a lot of entries about finding corrosion on connections , but none of the connections I have been able to get to look bad a t all, as the previous owner seemed to take good care of the bike and was stored in heated garage.
I find it weird that all winter, I stored in a fairly dry but unheated building, up on a wooden platform to keep it off of gravel floor that might had dampness, and it started every week or two on the first spin...but now, in the middle of summer, any little humidity seems to shut off the spark.
The switches all look great when loosened for inspection and the coils never look like any moisture gets to them , even after washing.
And once it starts, it runs great. I'm just worried that one of these days, it won't restart away from home, and I dare not spend the night away from home...I'm too old to push this thing home. It is either no spark at all, or baby let's go!
Thanks for info....I guess I might as well trailer it to the shop and let it sit until they can check every connection on the bike. I just don't have the hands or the patience for doing it myself.
If I didn't love this Vmax when it runs, it would find a new home....but I can't think of a bike I would ever be happy with after a Vmax.

 

[dj52l]

It has a new strong battery (6 months) and cranks good. Like I said, she fires on the first crank or she doesn't fire at all. It is the best idling and running bike I've ever had..once she fires. I've checked and wd-40'd plug wires and new plugs the last time it did this a month ago.
If it doesn't fire right off, I have been careful to not touch a thing when I come back, but turn the key and push switch, and boom, if it starts, she's fine until the next time it turns ugly on me... early mornings lately.
Now, the last 4 days in a row, It will not start at 7 Am, but try it again at noon and she starts right up. But today , still not starting at 1 PM after pushing it out into sun at 95 degrees.
I did the same thing yesterday, started about noon, so I rode a short ways, (too hot) and yesterday evening, I rode into storage building ahead of 1 " rain. Humid this morning and no start!.

 

[dj52l]

one more question,...is taking the airbox off the only way to get to the black box ?? I can't even see it with the side scoops off. i stopped by a Yamaha shop out of town and saw a Vmax stripped down and there the black box was in all its glory, but I can't even see the thing with the airbox bottom still on.

 

[dj52l]

Ok, an hour ago, I pushed it out in the hot sun , had tried 4 times since 7 AM to start.. just now went out and it started right up. It has done this 4 days in a row and has not been rained on, but humidity was rather high each morning???
Too hot to ride now! This thing has a mind of its own!

 

[jfeagins]

WHEN YOU DO HAVE IT RUNNING - CHECK THE CHARGING VOLTAGE both at idle speed and as you slowly rev the engine. That'll tell you where you stand on the charging system connections.

I'm telling you, I've had the same symptoms as this before. I would go to ride it to work in the morning only to have it crank and crank, but not start. I'd drive to work in my car, return home in the PM and go start the bike right up. WTF? My bike would also, occasionally, do weird stuff like misfire (ONLY WHEN VERY HOT), and die in traffic - even though I had put new plugs, plug caps, and plug wires on it. All that went away AFTER I improved the charging system and installed the next size bigger battery. Knock on wood, it won't happen to me again.

If you take it to the stealership, you get screwed pooch EVERY TIME, and their hourly rates are usually off the charts nowadays. You need to hook up with someone nearest you (from the forum) that does know how to perform some of these minor inspections, tests and repairs.

 

[m-cman]

You might check the modified sidestand switch for connection problems.

 

[jfeagins]

I'm thinking the side stand switch connection (if bad) wouldn't allow any cranking to happen.

 

[dj52l]

After I bought it late last Summer, i checked the battery that was supposed to be new, as it didn't seem too strong after a 4 hour ride, and found it dry as a bone. I installed new battery, careful to follow instructions on prepping for 24 hours, checked charging and found the regulator over charging at about 17.5 volts . so I replaced regulator and it has checked in spec since then and can't tell that there has been any charging problems since. 13-13.5 at idle, up to 14.5 at 3000. Always spins good. I did hook up the trickle charge when it sat for 4 days in May, as I would try it several times a day. Couldn't find a bad connection or switch anywhere then , but I never could get under the airbox at that time, so CDI and front coils were about the only thing not checked.
I rode about 3 days a week from Mid February in cold moist mornings to work and some pleasure riding evenings, until about May 20 with no problems other than the hour to dry out if rinsed off. Then, about May 20, I gave her a good shine up for a weekend ride, and never got her started for 4 days. Ever since then, everytime the humidity goes up, she won't start in early morning.
I tried to see just how the kick stand had been wired around and couldn't see anything obvious underneath around the stand and switch......it just has never mattered where the kickstand was since I had it, it runs up or down. That is where I suspicioned,a wiring problem, so I've been careful to not move the bike at all when I come back to restart, and it fires up. I've cleaned up all around the kickstand switch.
Guess i'll let her sit in todays hot sun and maybe a bit of moisture somewhere will dry up for good, as we have been having high humidity for a month. She starts right now.

 

[Bill Seward]

Bad coils??
My '85 would be finicky after a wash, rain or even high humdity. It always started, but sometimes it was a VMax 900 or 600. Eventually, it would get hot enough to dry stuff out. This situation was completely fixed immediately after the COPS modification. Immediate starts, wet or dry.

 

[jfeagins]

Bad coils??
My '85 would be finicky after a wash, rain or even high humdity. It always started, but sometimes it was a VMax 900 or 600. Eventually, it would get hot enough to dry stuff out. This situation was completely fixed immediately after the COPS modification. Immediate starts, wet or dry.

That right there would lead one to believe your problem was with moisture getting into the plug caps area, and/or the tiny pee pee holes in the heads were plugged up and not draining the water away from the plug seats.


Well, if DJ's problem it isn't a voltage thing, then I would think it was more a temp related issue with a broken wire somewhere, or bad solder area inside the CDI box. I'm thinking the midday temps being warmer might have as much to do with it going ahead and starting as opposed to it being a morning moisture problem.

Could it be a fractured pickup wire?

My old XS 1100 had a recurring issue with tiny broken wires from its' pickup coils over to its' timing advance mech. Darn thing would be fine - until I spray washed it. Then it would only run on two cylinders or not at all. Problem would go away as the bike warmed back up. Would have SWORN, and bet money the water was getting in somewhere, but it was the wire not connecting properly - couldn't see a thing wrong with the wire from the outside. Cool it off, no connection. Warm it up, connection was fine.

I know the Vmax is electronic advance, so maybe the CDI box itself is at fault???????????

 

[dj52l]

Thanks again for all off your ideas...it still could be any of them. I have checked the "pee-pee" holes last month when the problem started, after an out of town tech showed them to me as he named some possible problems. (nearest cycle shop is 25 miles away)
This afternoon, I took it on a ride after it started, for about 50 miles in 90+ degrees and it ran smooth as silk and had the old boost on tap anytime..everything great. I headed home as clouds began to build and pulled into garage 2 minutes before another inch of rain. Guess I'll see what she does in the morning.
In my rural area, it is all cruisers and Harleys and dirt bikes and I have only known 1 other Vmax within 30 miles, so I don't have many experts to discuss this with. Even my closest Yamaha tech has only worked on a couple several years ago.
I used to ride a 750 Seca daily through any kind of weather and loved a good rain to ride in...that old bike never failed to go in wet weather including one side wind & rain I could hardly hold on the road leaning way to the left. This one, I'm afraid to let the dew settle on it right now.
Thanks again friends.

 

[Rhoy Carter]

On my 85, I cured problems like you are having. First I pulled the TCI box and sprayed silicone lubricant into the vent holes on the botton side, I tried to drown it. The next thing I did was do an overkill with dielectric grease in every connection on the bike including the plug wires. I have not had a problem since.

 

[dj52l]

Checked bike last evening after another big rain, very humid, it started fine. This morning, no start. Just the dampness in the graveled floor of garage must have enough moisture to cause problem. It is now sitting out in the sun to dry out.
Does anyone know where I can get big bags of that silicon gel to stuff in every nook and cranny of the bike? I think I'm going to have to build a ramp into my living room to park it.
It is just too hot to start dismantling it this week to go through every connection, so I guess I'll find something to do in my a/c'd truck for the rest of my vacation. I was to take 2 weeks off and try to get my blood pressure down, Dr's orders, but this isn't helping...I had planned to go on a few relaxing rides.
What I can't understand is why it runs so good when it does start. Not a hiccup ever.
I just hope when I start dismantling and inspecting every thing and greasing and resealing, I can get the thing back together, as I'm just not good mechanically handed, more of a computer operator.
Lots of good ideas though, thanks.

 

[dj52l]

I just viewed the step by step instructions and pictures of the COPS installation. Those are fantastic photos and instructions, but out of my expertise and patience to do. But I did learn where some of the "stuff" is located under the air box. Now if I can find someone near me with the talent to tackle the mod for a fair fee, I'd have it done. Thanks!

 

[Redbone]

If I didn't have the engine out I would have just left the front coils in. The rears are easy to take out. Take off the airbox, pull the wires out of the coils and cover with tape, unplug from harness plug in COPs and you should be good to go.
I am really happy that I did this mod as Redbone starts easier, and probably runs better for it. unk:

 

[Bill Seward]

DJ521:
Is that Albion NY? If so, I'd be happy to give you a hand with the COPS install. If you're really unsure of your ability, I'd do the job for a small fee..... (Small Fee=Do someone else a favor, or donate a few bucks to your local SPCA. I wouldn't charge a VMaxer for help.)
I live in Holland NY, not too far from you if you live in Albion NY. Get the parts, and figure about 2 hours to do it. I did not remove the front coils, just cut off the connectors.
PM me if you want a hand.

 

[dj52l]

Thanks for the fantastic offer, but I live in Illinois. Deep south eastern Illinois in fact. You know, where our Ex-Governors make our license plates by hand for us. (They go straight from the White house to the Big house) Except they were elected by Chicago, not us Southern Illinois-ers. They don't know we exist.
I rode last evening with no problem at all. Parked it overnight in a different dry garage, and this morning, no start.
I know a local who just started a small Harley repair shop...maybe he is looking for work and would take on the job for a lower rate than the normal Yamaha shops. Although here in rural Midwest, we have a lower rate than most areas, about $65.00/hr.
I must admit, I'm starting to look longingly at ST1100-ST1300's that are ready to go everytime you hit the starter and sound like a sewing machine, but then I hear that Vmax when she fires, and my heart says no way!
Maybe I can buy a used tanning booth to park the Vmax in and warm her up before I want to ride .