Wont start in cold weather?

[bernside]

Hi everybody,

My name is Cliff and I'm from New Bern, NC.

I am trying to help my Dad out with a problem he is having with his vmax.

The bike wont start in cold weather (below 50 degrees). It will turn over until you kill the battery, but no go. With the choke full on, it sounds like it wants to catch at first then nothing. Without the choke or half choke, nothing.

Set a heater up aiming at the carbs and after a bit it will start right up and run great all day, stops and restarts included.

The bike is stock except for a supertrapp exhaust. It runs great once its warmed up and no other problems. It has low miles and lives indoors

I hope someone here can point me in a likely direction before I start taking things apart. :biglaugh:

Thanks in advance,

Cliff

 

[maxcruiser]

Cliff, start with the basics first, what condition are the sparkplugs - before trying to start bike - colour & plug gap?

After trying to start bike - are the plugs wet or dry?

Once this is answered, we can move on to further diagnoses.

Mike

 

[davidon]

Weak battery..check this..need 12.8 volts

 

[4gasem]

Water in the fuel?:ummm: condensation is our enemy! Make sure he's using a good fuel system cleaner and stabilizer like Seafoam which you can get at the local auto parts store.:thumbs up:

 

[bernside]

Cliff, start with the basics first, what condition are the sparkplugs - before trying to start bike - colour & plug gap?

After trying to start bike - are the plugs wet or dry?

Once this is answered, we can move on to further diagnoses.

Mike

Mike - plugs look good, nothing out of ordinary there. Dont remember the gap offhand, it hasnt been changed recently though.

Battery is good - bike starts fine with a little heat.
Gas is OK, he has run several tanks through and still has the same problem.

I am into old bikes so I know the routine on all the basic stuff, but I know squat about vmaxes and I am trying to help long distance.

I was thinking there might be a sensor? or something that goes bad. I was hoping it was a common quirk/problem.

Thanks

oh yeah, the bike is a 2004 with 10,000 miles.

 

[eatatjoz]

With the bike cold and under 50 degrees, pull a plug and check for spark.

This sounds like a cracked or cold solder joint on the TCI.

 

[maxcruiser]

With the bike cold and under 50 degrees, pull a plug and check for spark.

This sounds like a cracked or cold solder joint on the TCI.

+1 to above - but if you have spark when cold - than not electrical - than it's fuel related - next would be to drain carb bowls and see if water in the fuel - if not, than need to check fuel pump operation (bad ground), fuel filter, etc...

This is not a common problem (ie: bad sensors) for vmaxs but hopefully it's just something minor.

Mike

 

[113s&s]

may be no help here but my max always needs the throttle cracked with first cold start with choke on

 

[bernside]

Thanks guys.
My Dad will be back next weekend and we will pull the plugs and see whats what.

I'll be sure to post the fix when we figure it out in case someone else has the same problem.

-Cliff

 

[Rusty McNeil]

Fuel and battery good, no water in gas etc, good.

Checking spark can get kind of subjective; looks kinda weak even when good.

Have the carbs never been messed with or are they completely stock?

When it does finally start does it run fine or chug-chug like all cylinders are not firing for a little bit till they warm up and start firing?

Mine starts even in 30 degree temps (sever cold weather for Houston:eusa_dance instantly with full choke and no throttle.

Are all 4 fuel enrichment plungers moving in and out when operating the choke lever?

You might also put a meter (analog preferably, so you can really see where the needle goes, it's kind of hard to see on an digital meter unless it has an analog reference bar) on the battery AND THEN start it. I have had several batteries show good voltage but when put under load they go to shit, it's amplified by being cold.

Battery voltage probably shouldn't dip below 10-10.5 volts while cranking, preferably not that low.

When it cranks but doesn't start is it turning over vigorously or sluggish like a weak battery?

The TCI box can be a bitch to troubleshoot because usually it's an intermittent failure at first, or was for me anyway. Mine would act stupid when it got hot, the problem would come and go and I never definetively diagnosed the TCI as the problem untill I just replaced it and it fixed the problem.

Sometimes the cases on the Vmax coils will start cracking also. Mine were cracked all to hell but tested fine and I've been told this is not always a problem. I replaced them anyway with Dyna coils when I did the TCI.

After doing all the easy stuff I would rebuild the carbs before I spent money on what I though was a bad TCI.

 

[bernside]

Have the carbs never been messed with or are they completely stock?

When it does finally start does it run fine or chug-chug like all cylinders are not firing for a little bit till they warm up and start firing?

Are all 4 fuel enrichment plungers moving in and out when operating the choke lever?

When it cranks but doesn't start is it turning over vigorously or sluggish like a weak battery?

The carbs are stock.

Once it starts it runs fine.

I don't know about the plungers, this is definitely something I will check when I go to my Dad's next weekend.

I talked to my Dad about it again and he said,

"I don't think electrical. If you open and close the throttle first and then hit the starter with the throttle closed the bike fires, but does not start. Now if you engage the enricher nothing happens! At that point you need starter fluid or a heater to warm things up."

Maybe this will provide more clues.

I appreciate the help guys, this advice will cut down on the amount of time I spend messing with this (hopefully).

-C

 

[maleko89]

I would check choke first and make sure the linkages/plungers are truly opening. Might want to test battery too and make sure cranking voltage is sufficient. Other than that, have you checked float level?

Mark
#1098

 

[KJShover]

+1 on the battery and the choke.

Up here its not uncommon to go riding in the 40's. I agree with putting a meter on your battery, what looks good static dies when there is a load on it. and you mentioned heating the carbs? are you localizing the heat or just putting the heat on the bike heating the battery as well.

Also another thing that comes to mind that I've seen up here is the oil. what is the weight of oil being used.

A friend of mine was having a similar problem with his bike and it turned out to be as simple as the thick oil he was running, and thus when he put the heat to the bike it heated up everything and all was well.