Randomly dying at operating temp

[Fire-medic]

Have you checked that the tank breather is clear and of pinched?

Radnecksoldier said his tank was shiny-clean, except at the top of the gas tank. I suppose he may have used a fiber optic scope cable for a cellphone to see the top of the gas tank interior. Evidently, his vent for the tank would become plugged and cause fuel starvation. This happened intermittently.

I recommend ~6% 'cleaning' vinegar to clean a rusted gas tank. Remove the reserve fuel sensor if you use vinegar! If you don't, and if you leave the gas tank reserve fuel sensor in a vinegar bath long-enough, it will dissolve! Replace the reserve fuel sensor with a block-off plate. Home Depot has up to 30% cleaning vinegar. The 6% works well, and I usually leave it soaking for 1-2 days, monitoring things every 4-6 hours. I fill the gas tank, and leave it inside a plastic container like a Rubbermaid storage container to contain any spills. You can save and re-use the vinegar, I store it in a plastic gas tank with a big label on it: VINEGAR.

 

[Jack Hammer]

All good points. I'll add one more. Kickstand switch, make sure your return spring keeps the stand up solid. I remember a bro of mine when I was living in California had similar issues, he would ride over rough road patches and the damn thing would die. New spring, goodbye problem.

Other point, cutting off connectors and soldering wires. Might cure the problem but a pain when you need to take it apart. Unless the wires are burnt, you could try electrical connector paste.

 

[Hinterwaldler]

Tank is fine.

It is rare and intermittant, not constant or predictable. It happened on 2 occassions this summer and the last had it running long enough to fill the bowls then would stop again and sit until I could get the bowls full. The filter is clear and full of fuel and the pump would run and shut off like you would think it should but the bowls weren't filling quickly. Once the bowls filled, it would start and run half a mile or so until they ran out of fuel. I was about 6 miles from home and it took about 30 or 45 minutes to get home stopping every mile or so. At the last stop the battery had gotten so drained from trying to start that I thought it would not start but it did and I did a full throttle run then neutral coast and made it to the drive (live in the country on a 2 lane so full throttle was an option, else I undoubtedly would have been walking that last half a mile).

I did a charge check and found the battery had a good connection with the R/R but it was only about 13.1 volts running at best. I replaced it with a newer style r/r (cooling fins..for '96 up) and now have the 14-14.2 vdc at the batt but I don't really think that is it, lights didn't dim and battery had enough power to turn the bike over at several stops minutes apart so should have at least run the pump well enough to keep fuel in the carbs.

I've had it a year and haven't had the issue until a couple of months ago. I ordered a new pump thinking maybe it was losing it's prime....in my experience what it seems like.... but when I examined the pump on the bike it looks like it is fairly new and is attached with nylon ties. Don't know how it originally attached and haven't compared it to the new one. though by appearances it appears to be OEM design and size, I wonder if it is aftermarket and dimensions were too big to mount it with the stock mounts or maybe the person just misplaced the mounting bracket? Maybe it was replaced because a previous owner had the same issue in the past??

I started it yesterday after putting on the newer r/r. I noticed the fuel pump is running slowly at idle...not cycling off and on like one would expect but at a slow run. Maybe it is a pump issue or maybe something in the tank partially blocking the uptake end of the hose. I don't know if these have a filter of some type in the tank or just an open orifice/hose end. I will take a closer look at the pump and measure its output and work my way back to the tank but I don't think it should run much at all at idle. If it is running to keep up with fuel sipping at idle, no wonder the bowls are getting sucked dry at cruise or above.

 

[02GF74]

How do you know the bowls are full?

From what you say, it sounds like the fuel pump is unable to keep up with demand, the fact that it looks new doesn't mean its working properly.

Have you check the fuel filter - there oughta be one before the fuel pump.
Also as you plan to do, you need to check the flow - connect a hose from the fue; pump and measure volume in a given time and compare flow to spec - or do rough calc using mpg.

Note that when the engine is not running, the pump runs for about 10 seconds before power to it is cut off.... so you may beant to unplug the power to it and connect to battery for the flow test.

 

[Hinterwaldler]

By full I obviously mean there is enough to start and run. No, I didn't disassemble the carbs on the side of the road with my multi-tool and measure the float height before starting with my micrometer to make sure they are "full".

Hmmm, fuel pump can't keep up with demand.....that's kinda what I was beating around the bush saying since the fuel pump is running constantly at idle.

OK, let me stop there before I become a total azz in my response and explain before I hack off the community with my responses to answers that come as though they were directed at an 18 year old gamer noob.

I have been doing this for well over 50 years, built bikes and cars so, yes....I did check my filter. Actually it is an aftermarket glass filter I can see thru (opposed to the plastic factory one that you can't).

Only fuel since I have had it is ETOH-free 91 octane unleaded. It gets a spritz of Stabil in the fuel tank in the fall as I am tucking it in for winter. Over the winter, it gets started and run to warm-up several times and then a spritz or two of Seafoam in the fuel during the riding season.

I realize there are a lot of noobs and novices and just plain not mechanically minded persons on here. I am not one.

I did just join a few months ago, not because I am inept or inexperienced but because over the years I have found these forums and message boards invaluable to glean intel from others and occasionally share something I might have picked up over the years, as necessary. I also find them especially useful in the instance when I am scratching my head about something I can come here and get a wide range of input since it isn't like I can go to the local Yamaha dealer or another local V-Max owner and ask a bunch of V-Max questions...

I bought my first V-Max (banana yellow 1985 that I had repainted to 1970 Dodge PlumCrazy) after I returned from Desert Storm before the days of internet. I was an original member of the V-Max Owners Group when it was a member by mail only group out of Conn or Md or one of the states on the east coast. I got rid of the 85 in 1996 with a bad 2nd gear. I did early (now common) mods such as disabling the V-boost, K&N filter, Jet kit, suspension drop, and it had a 4-2-1 Kerker when I bought it.

I missed it until last year before I turned 62 when I decided to put a return to Mr Max on my bucket list before I lost ability or motivation to enjoy the ride. Of all the bikes I have owned and built and ridden over the years, I have to put a properly setup and tuned V-Max at the top of the list for something with raw unleashed power that has a comfortable enough ride that I can ride all day long and wake up ready for another day of riding as well as durability, mechanical stability and even fuel mileage is not bad for umpteen zillion drag-race inspired wheel hp bike. I can poke around town all day and as I move out to the interstate, I can quickly and immediately widen the eyes of any crotcher out there trying to keep up on the merging lane.

I bought this one with plans... one of which is that I hope for some lucky individual to find it sitting in my shed under a tarp as a 'barn find' some day after I find my favorite tree and sit down to take a dirt nap underneath it.

But I regress.....And now back to topic

As I said, since the pump seems to be constantly running while the bike is at idle, I will start at the pump and work my way back to the tank since it feels like a pump issue (yes that's a gut feeling and after 50 years of this, I have found that my gut feelings generally seem somehow to be pretty close to where I should focus) and after looking online at a picture of an oem pump with the bracket and mounting studs built on, the pump on my bike is obviously an after market "works for this application" pump but not a factory pump with the built on bracket and mounting studs. The previous owner did not mention replacing the pump so it may be 2 years or 20 years old...I have no real idea and if it is a ChinaBilt pump, it may not have been the best quality pump to begin with.

I will undoubtedly get it figured out eventually. I don't have a garage or even carport where I live so I was just looking for common complaints and possible solutions found to any issue similar to mine to hopefully shortcut my troubleshooting time in the dirt and peagravel drive under the hickory and oak trees.

Thanks to all who have responded. If you have gotten this far in the novel, thank you for your patience. And I do apologize for being short in my response. Sometimes it helps to know if you are talking to grandpa or grandson, just be aware if it's grandpa, he can be cantankerous and cranky if "triggered" (a word not even in my vocabulary until the past couple of years).

 

[MaxMidnight]

Assuming it is fuel starvation then with the OE pump there is the occasional issue with the contacts and non-return valve and as mentioned previously blocked or pinched tank breather.
Not sure how nuch good OE pumps go for but it may be worthwhile trying to beg, steal or borrow one so you can rule that out as the cause.

 

[Fire-medic]

Doesn't Holley make a reasonably-priced inline fuel pump?

 

[Jack Hammer]

I'm wondering why you got triggered. People here tried to help you. If a noob offers you his thoughts then how would that take anything away from the issue?

I'm not a noob but I do take all the advice into account who ever is willing to donate.

 

[02GF74]

By full I obviously mean there is enough to start and run. No, I didn't disassemble the carbs on the side of the road with my multi-tool and measure the float height before starting with my micrometer to make sure they are "full".

Hmmm, fuel pump can't keep up with demand.....that's kinda what I was beating around the bush saying since the fuel pump is running constantly at idle.

OK, let me stop there before I become a total azz in my response and explain before I hack off the community with my responses to answers that come as though they were directed at an 18 year old gamer noob.

I have been doing this for well over 50 years, built bikes and cars so

Let me ask you this. When you were working on your bike, when you looked around you, did you see me there? In other words, we on this forum are trying to help out remotely without seeing the actual problem, for all I/we know there could be fuel pissing out of one of the carbs that is obvious when you are next to the bike but soemthing you did not mention.

Let me give 2 examples of the difficulties of trying to diagnose remotely.
Ex 1. Mains fuse keeps blowing when turning the ignition on, but light all work. Lots of suggestions but it turns out the OP wired the battery in reverse - no mention of that but something that would be obvious (?) if one was tracing through the electrics.

Ex 2. Bike won't turn over. Lots of suggestions on tracing the starter circuit etc. Then OP posts photo of the bare starter solenoid posts. Turns out the solenoid was not wired up. Again something that should be obvious (?) if one was tracing through the electrics.

Now let me ask you this. Although I worked for quite a few months in Rhode Island and Texas, I am certain we have never met so from your post, how can I tell if you are an experienced mechanic or someone who lets the local shop do the work?

So if you felt insulted, that was not my intention but I my approach is to ask simple questions to get a simple answer to try to figure stuff out step by step.

I asked you how do you know they float bowls were full of fuel
Your sarcastic reply:

re: No, I didn't disassemble the carbs on the side of the road with my multi-tool and measure the float height before starting with my micrometer to make sure they are "full".

Basically as far as I can tell, you don't know if they are full or not. Can you tell me there is not a sticking float or some other obstruction so that one or more carbs are not receiving fuel?

One way to investigate is to undo the drain screws and capture the fuel as if comes out, then compare volumes.
Another way is to connect a transparent tube to show the level of fuel in the carb, obviously the bike cannot move unless the hoses are long and secured.



Anyways, let us know how you get on.

Do you have a copy of the sevice manual?
Have the carbs been serviced?

 

[Fire-medic]

02GF74 is one of the frequent posters who tries to help anyone posting about their bike's problems. He isn't in the habit of insulting those who do post. Accept the assistance without feeling that people are giving you a hard time. When you finally post, "it was ________'" then we all file that away, so if another similar case arises, your issue may help shorten the time the rider has the bike off the road.