running last night. won't start today

NOT when they're cold!
These babies are a bitch to start ... COLD!
Late Fall and Winter cold.
It took me 25-minutes to get my 750 Max to pop, this week.
I resorted to Starting Fluid shot right into the void behind the Air Filter.

 

Would be interesting to know what the voltage drop is between fully charged and when you turn the ignition over. I woud throw a voltage meter on the battery and turn it over - see what the voltage drops to under load. Of course this woud not account for why it wouldn't start when trying to "bump start" it, but could be two separate issues. Coud be a combination of lower battery (voltage drop) and dirty / clogged enrichment circuit - I would want to rule out battery first. I am sure someone on the forum much more experienced then I could tell you what the minimum "voltage under load" when turning ignition over should be. I know I read it some where in the forum posts but can't seem to locate it now.

I know there is a fine line between what is believed to be a fully charged and functional good battery and one that will start these bikes.

 

That's way too cold to be starting an XJ. The starter is going to draw some serious power away from the battery and not leave enough for the ignition to work. Are you actually riding this bike in this type of weather? If the roads are full of salt that's going to eat on all your metal parts big time.

MN

 

like the others have already mentioned, I'm just reiterating the fact that these bikes are cold-blooded. unless you have a real reasoning to be riding in temperatures like that you may as well work on anything else besides trying to start the bike. winter season is a good time to disassemble carbs for regular maintenance, clean engine covers, and other seasonal maintenance. its been in the 20's and 30's for several weeks here in Ohio, so I took the battery out. not worth fighting against mother nature

I've also been told that random starts on an engine in temperatures that cold does more harm than good; unless you fully warm the bike for 20 minutes of riding. the temperature effects cause condensation but don't quote me on that. anyone else know more about this?

 

This will be the last I comment on this thread...

Please read what *I* posted before you make yourself look like a jack@ss... I said to remove the relay, not bypass JUST the kickstand switch.

You've got a weird way of accepting help.

I'm out.

 

Doh.....

must be the cold weather then..... I ride until it's icy out. I even rode on the snow. Lots of fun! Just wash the bike after.

I suppose the battery being on the weak side is probably one of the problems as well as the cold.

my enricher system is working fine.


it'd be nice to figure out what's a reasonable voltage drop when i'm cranking over.

 

http://www.xjbikes.com/Forums/viewtopic/t=27543.html

The above link might help - Chacal (supporting Vendor) authored "The Utimate Relay, Switch, Sensor, and Diodes Guide" -- the last post very bottom speaks to testing / and specs required for a good strong battery. Required load voltages are aslo specified.

 

You are absolutely correct and for the reason you stated. Starting the bike in really cold weather without fully warming it up (as in a good 20-minute ride) to burn off all the resultant internal condensation can wreak havoc in the engine and exhaust system. I can't think of a quicker way to ensure your mufflers rust out.

 

Yea I usually start it because i have to ride it...... unless it's to make sure i didn't f*** something up cuz i'm working on it in which case i'd have the portable heater on in my garage so it's somewhat comfortable

And yes i'm very very well aware of it being extremely bad to start and shut off without being warmed up.

 

what is this "brushes" people talk about? is it actually wire brushes? how much are they approximately?

 

Brushes are located under the altenator/ generator cover and recharge your battery and provide electrical power to lights, indicators ect.

Your bike will need a good sound battery to start the bike, any abused or old battery is unlikely to hold sufficient charge.

Use chacal's guide and check your batteries output and measure voltage.

 

They're little carbon blocks; like the "brushes" in an electric motor. They're located IN the cover and run against the face of the rotor. They wear down. They have little "wear limit lines" in them; once you can't see the lines, they're less than 11mm long (the "service limit") and need to be replaced. The factory books claim they'll need to be replaced at 10K miles; they tend to last twice that provided everything is clean, dry and oil-free in the alternator housing.

Generally, a new brush/holder assembly is available for around $20. Check with XJ4Ever (chacal.)

 

I'm suspecting that a new juicy battery, fresh starter brushes, plus fresh alternator brushes/parts would really help crank the motor over better....


time for some tests to see how my charging system and battery are doing

 

rd337,

What does your starter button look like? Might check inside the control switch to ensure the wiring to your contact plate is still soldered solid.

Gary

 

i'm not having problems with the button..... unless you're telling me the power that goes to the starter goes through the button thus a poor contact on my button means insufficient voltage going to my starter.....

 

rd337,

There's a contact plate inside the control switch behind the button/spring. When you push the button a signal is sent to the solenoid at which time the large charge necessary to start your bike is sent to your starter. If the wiring soldered to that contact plate is loose or not connected the signal will not happen. I had this problem; took the switch apart, cleaned all the parts, stripped and re-soldered the wiring (I had ONE thin wire connected to the contact plate), new button and spring...varoooom. Hope this helps.

Gary

 

but the starter is cranking just fine. if the button flips a relay and the button is faulty then the starter shud be either on or off, not week

 

"Cranking just fine" is automobile speak. These XJs have fairly robust starters that are able to crank even when there isn't enough left for adequate ignition to start -- i.e., starter cranks, engine won't fire.

Do yourself a favor. If you want to ride this thing close to zero degrees, get a new AGM maintenance-free battery from Chacal, enjoy the benefits of higher cold-cranking amps and longer life (double or triple) and put the battery question to bed. Then you can move on from there. I know I'm never going back to an acid battery for mine.

 

It has a new yuasa battery as of this past spring.... it's holding up at around 13V

I cleaned up the contacts in the start button and the switch. no problems with it before, and didn't make a difference after.

Would the ..... i don't know what you call it..... the part which the key goes into to turn it on and off..... would that possibly be an issue?

I got some valve shims as a couple of mine were a hair out of spec last time i checked a month ago.

Gonna pull everything apart, seafoam into the gas, bomb the carbs with carb cleaner spray, do whatever i can to clean up the carbs a bit more without having to tear her apart. replace the valve shims, seafoam into oil before a nice oil change.

I want this all done within one night. I really don't think the carbs were dirty at all. I always use the best gas and it's been running fine so far.


A couple questions.

Is there only one drain plug? i heard there are two but do i only bother with the one under the filter? or should i find the second one and drain from there too?

And would an inline fuel filter be a good idea or is it unnessisary?

 

.... it's holding up at around 13V

I am assuming this 13V is standing voltage - no draw or load on battery, but what is the battery voltage while turning engine over ??

The ignition switch (where the key goes in) would have no bearing on your issues, based on your previous posts that the bike is turning over but just not firing - is that correct ?.

As far as your question about the need for an inline fuel filter ..Yes, it is highly recommended if not a must.