94 Vmax, just did a fresh valve job and I home ported the heads with new Cometic gaskets and arp studs and installed fogger nozzles into the intakes... Runs like shit, keep fouling number 4 plug... Valve timing is perfect, I lashed all the valves, it has 185psi on all 4 cylinders.. I checked and it has great spark.. Been through the carbs twice now and I know they are clean and the float levels are set right. I mean it's got spark, compression and fuel so it should run??? It's just number 4 too, I'm going to try moving that coil to another cylinder tomorrow (I have a COPS kit from Gannon) but it is sparking so I doubt that's it... Any ideas?? I'm getting seriously pissed!! :bang head::bang head::bang head::bang head::bang head::bang head::bang head:
Someone help me before I push this thing over a cliff....
Help Support VMAX Forum:
ninjaneer
Well-Known Member
how's the saying go? "fuel, spark, and AIR". fouling a plug=too rich. so maybe the carb needs more air? maybe the other way around--carb needs less fuel.
ninjaneer
Well-Known Member
#4's a/f mix? some guys have different number of turns for each carb.
KJShover
Proud Vmax lover
Ok I read the thread on setting wet float levels but I'm a little confused, do I just leave the stock drain tube in place in the rack and attach a clear hose to it with the marks? If so depending how far you slide the clear hose on the stock drain tube wont that throw off your marks on the end for the setting? I'm a little confused.... I set the floats dry on the bench at 1 1/8" and all the needle and seats looked perfect... The floats made a nice little "click" on the needle and seat so I thought sure they were working right. The thing ran flawless when I parked it and has never fouled plugs before... I was thinking that coil or the Dyna but it is sparking when I have the plug out and resting on the head... I'm so tired of working on this damn thing, beautiful weather this weekend and again I'm without a damn bike...
Not sure how much I can help either. You can add on the clear line as you mentioned and it won't matter the length since it will only add more fuel to compensate. I'm not sure what effects your port work has had on the setup too. Done right you can make more power and done wrong you can really kill it. I have no idea which you are dealing with.
A bad box can still cause a problem but you've already tried two different units so I would think you can eliminate that one.
Diaphragms are good too I assume?
A bad box can still cause a problem but you've already tried two different units so I would think you can eliminate that one.
Diaphragms are good too I assume?
Diaphragms are perfect Sean, I put a stock box on it and it ran like shit because I have the COPS kit from Gannon with the resistors built in for the Dyna, Guess I could throw together some makeshift ones and try it again.. I can't see where port work would make it foul a plug with fuel and for having a fouled plug the things an animal, it's almost as fast as it was before but you can "hear" that it's not right at idle and at full throttle... I'm gonna try moving that coil around and see if the problem follows it because that's the easiest thing, after that I'll try making a new harness and trying the stock computer again, shouldn't have fucked with it..
You can just add clear hose to the drain. If it's outlet is higher than the top of the carby, you can run the bike like that and see if the fuel level creeps up.
I did the float levels on mine and it started running crap a month or two later. Then it started spilling fuel out the overflow.
I popped off the carbs and checked it out (no. 4 it was). It seemed fine and set right. It shut off if I blew through the line etc etc
Put it back together after fitting a new filter. Still the same.
At the moment I have given up on "fixing" it, and am waiting for new needles and seats and gaskets and o-rings and diaphragms.
The coils swap is probably a good idea, as is a spark plug swap.
My COPS harness I made with resistors, and it worked fine on the standard black box.
I did the float levels on mine and it started running crap a month or two later. Then it started spilling fuel out the overflow.
I popped off the carbs and checked it out (no. 4 it was). It seemed fine and set right. It shut off if I blew through the line etc etc
Put it back together after fitting a new filter. Still the same.
At the moment I have given up on "fixing" it, and am waiting for new needles and seats and gaskets and o-rings and diaphragms.
The coils swap is probably a good idea, as is a spark plug swap.
My COPS harness I made with resistors, and it worked fine on the standard black box.
naughtyG
Well-Known Member
I assume you have tried replacing your spark plugs too? Even one that looks like it sparks just fine may be crap - and so cheap you just gotta give it a go..
Now you have my curiousity aroused, mine ran like shit with my factory box... Might be a Dyna issue, still gonna try the coil swap... I don't think its the plug because this is the 3'rd set and all have done the same thing... I don't regret cleaning the carbs cause around the jet blocks was dirty but not so bad to make it do this... Thanks for the advice guys, gonna check wet float level and mess with the coils and dyna next...
Sent from my ADR6400L using Tapatalk 2
TurcoLoco
Well-Known Member
Curious, what is the gap you are using on the plugs?
Running a .35 gap... Is there a possibility that the coasting enrichener could be doing it? I didn't get into those because I didn't want to have to get into resetting the sync screws and stuff so I only split them into pairs to clean them...
Sent from my ADR6400L using Tapatalk 2
Sent from my ADR6400L using Tapatalk 2
Yea I've had 3 different sets in there, like you said its a good idea though...
Sent from my ADR6400L using Tapatalk 2
Redbone
Well-Known Member
I use the COP's w/ resistors on a stock('92) box with no issues. I also run my plugs @ .027, actually Birdoprey recommended .022 but I found that Redbone liked a little bigger gap. I hope you get this issue nailed down!
jedi-
Well-Known Member
I usually try and work with process of elimination principle for my troubles.....if you could just get hold of a known good set of carbs you could easily prove if it is/isn't your problem, then work from there.
Mine were perfect when I pulled them in the fall, I'm leaning more and more towards ignition... Gonna tighten the gap and move that coil first, if the problem follows that coil then we have a winner.. if its still in number 4 then I'll try the stock box again and the stock coils.. if that doesn't fix it then however unlikely it must be that number 4 carb...
Sent from my ADR6400L using Tapatalk 2
PATMAX
Well-Known Member
I have been preaching the benefits of having a known " good" set of carbs on hand for everyone! I have two racks of carbs on hand. One ready to go that are drained and oiled and another set ultrasonically tanked and ready for full rebuild. I know you are frustrated and SpecOps can attest to a bike driving one to near insanity, right Dave?!
Anyhow, I was gonna suggest switching around jet blocks and maybe float needle and seats from another carb and see if the problem follows. Sean will probably chime in if this cannot or should not be done. But of course, you may not tear down carbs again. Don't forget Sean has the electrical test program and can send you parts to try and test against your parts.
Don't give up, we'll keep helping you out.
PATMAX
Anyhow, I was gonna suggest switching around jet blocks and maybe float needle and seats from another carb and see if the problem follows. Sean will probably chime in if this cannot or should not be done. But of course, you may not tear down carbs again. Don't forget Sean has the electrical test program and can send you parts to try and test against your parts.
Don't give up, we'll keep helping you out.
PATMAX
TurcoLoco
Well-Known Member
SRK, I am running mine at .026 as well. Gannon recommended setting them between .026 and .028. I think the plug comes at .035 by default but that is too big of a gap from what I was told. I have not tried .022 but .026 seems to be working fine.
You might want to experiment yourself but I suggest set them to something under .030 but I am not sure if this has anything to do with your problem.
I agree with PATMAX, if you plan on keeping the Max, you might want to look into having a spare set of used carbs at hand even just for troubleshooting purposes.
I have a total of 8 white hair, 6 due to issues with girlfriends, 2 due to Max issues.
:bang head:
One troubleshooting tip that served me well with computers seem to help with motorcycles as well: when a problem surfaces, always start by examining the last changes that occurred or you have made.
