2004 VMAX Idle Issues And More

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Yep, the rest is fine. Make sure plugs are grounded for sure though since it's hard on the ignition if the plugs don't fire. I made a simple doo-dad switch that plugs into the starter relay. It turns the starter but ignition isn't fired.
 
The easy way is to leave the key off and jump the solenoid terminals. Nothing is on that way.

Sean
 
Sean,

That sounds like the way to go. What is the location of the solenoid terminals?

Any help would be appreciated.


Thanks,

Jim
 
Sean,

That sounds like the way to go. What is the location of the solenoid terminals?

Any help would be appreciated.


Thanks,

Jim



Under your seat and above your battery, behind coils. the one with the red wire is your battery and the black one is solenoid I believe.
 
Hey Guys,


Just completed the compression test. When I pulled the plugs none of them were wet this time. These plugs were installed yesterday and they are all gray in color versus tan.


The compression test results were :

Left Front : 157 PSIG
Left Rear : 157 PSIG

Right Front : 165 PSIG
Right Rear : 152 PSIG


This test was done with bike warmed up. I had taken for a ride and the idle issues are all but gone. A little hesitation just off idle. Will get sync tool tomorrow and do that.

Seems it might be a little lean with the A/F screws 2.5 turns out on all carbs.


Take care,

Jim Spence
 
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Those numbers sound low to me. I would think the compression would be in the 170's on the low end. A weak battery will not turn the motor fast enough to get a good compression test.
 
Worthy of noting: too much ethanol content in your gas, or adding too much additive can also cause that slight hesitation off idle you're experiencing.

Vmax carbs don't seem to like much ethanol.
 
BG44K? Who sells this? Autozone or someplace? I would like to pick some of this up and try it out.

Thanks,

Jim

Jim, you may have to google BG and get the location of your nearest dealer.....it's kind of a wierd set-up but seems like little gas stations and engine shops may sell it but no big stores.

In fact I just got a can of 44K a couple hours ago for $16.99 tax included....seemed like a hell of a price to me!!
 
Thanks dan-o, will do.


As far as the compression test pressures, I thought the service manual said the high number was 171 psig?


Not sure.

Fighting a stuck on oil filter as we speak. What a pain.


Take care,

Jim Spence
 
Finally got that stuck oil filter off. Went out and bought a filter removal tool that fits a ratchet but even that would not turn the filter without slipping. Had to resort to the oil screw driver through the filter trick. Thank goodness that worked.

The oil was changed by the dealer maybe 200 - 300 miles ago but it looked like crap. Very dark. Did not expect it to be so dirty so quick. Its fresh now.

Received sync tool today and will be doing that.

Any other opinions on those compression numbers I posted yesterday? The battery is new and while doing the test the starter was spinning the engine freely. The shop did the break in maintenance at 600 miles and its only got 1000 miles on it. I wonder if they really checked the valve clearances. They are the same ones that cleaned my carbs but could not figure out why the idle would hang.

Thanks again for your help and info.


Take care,

Jim Spence
 
TBH I wouldn't trust that stealer's work at all. If your oil is dark after just 2-300 miles either there's something very wrong or they just didn't change it. When I change my Rotella-T after 2-3000 miles, it still looks golden brown, although darker than new. It is possible, however, that a sticking needle would have caused gas to get dumped in your sump, contaminating the oil. Did it smell of gas at all when you took it out?

I don't think your compression figures look bad at all - the manual states minimum 128, standard 142, max 171 PSI. Check the attached pic.

The valve clearances don't need checking for many miles (26,600). It's very unlikely they would be set wrong at the factory, and they won't go off when the motor isn't running.

Your hesitation off idle is most prolly due to shit gas (lots of ethanol), or maybe the A/F screws need a little tweak. Are they still blanked out (i.e. factory set?) What's your elevation?
 

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Hey Guys,

Just got through with the carb sync. Wow, what a mess.

Before the carb sync the idle would still hang a little before returning to idle at 1000 rpm. After doing the shotgun and the peashooter that issue was still there. After the bike was really warmed up the idle would drop to around 800 rpm and the slight hang was still there. If I used the idle adjust screw to raise idle back up to 1000 rpm I would get carb coughing and then the idle would shoot up to 2000 - 3000 rpm and would hang there. I would have to back the idle screw all the way out to get rid of the hanging which made my idle adjustment screw pretty much useless.

So, with the sync tool calibrated and hooked up I started the bike and the left two cylinders drew the liquid almost out the top while the right cylinders did not even register at all. That worried me. Not what I expected. I was confused at first. Then I figured that the right vs. left was so far out that I had to balance right to left first. As I turned the adjustment screw the left side would drop and finally the right side started to register and the idle started dropping below 800 rpm. So I adjusted the idle back to 1000 rpm and continued adjusting to get all four about equal and then did the procedure from start to finish and got them all spot on.

Now my idle adjust works, the hanging idle problem is completely gone, the bike sounds much better and revs much quicker. Can't wait to take a test ride. Those guys at the dealer had stated that they pulled the carbs 3 different times to get them clean, synced the carbs and still could not figure out the hanging idle issue.


Thanks to this board and the people on it I was able to do this myself and hopefully did it correctly. I know that this is not that hard but before reading up on this board I would not have even tried it myself.


Thanks to all,


Jim Spence
 
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Well done Jim!

Now go get your $$$ back from those useless stealers...

And do a nice burnout if front of their shop LOL

Happy riding!
 
Hey naughtyG,

The oil did not smell like gas. The a/f screws are already drilled out and set at 2.5 turns.

The carb sync helped a whole lot. I will be doing my own work from now on.


By the way, when I changed my oil I used that Rotella-T too.

Thanks for the input.


Take care,

Jim Spence
 
Im finding different numbers for the compression, My Clymer book says min = 170.6 psi, standard = 199.1 psi, max = 227.6 psi and the online manual just says 1422 kpa & 206 psi.
So now i would really like to know what the actual numbers are.
naughty G what book did you get the numbers from?
 
Rhoy, those are numbers from the Yami service manual. IMO, Clymer's numbers are inflated. I believe some of their number are from their '03 test bike.
 
No problem. My buddy's '99 was about 210 PSI on each cylinder and as far as he knows it was stock. It dyno'd with a 130 bhp at the time. It's like an instructor at Yamaha University pulled that bike out and said to the class "Okay, this is how you put together an engine".
 
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