Ignition woes (maybe)≥÷

[flyday58]

Turns out it's the fuel pump. Swapped fuel pump relays and still had the problem, unplugged the pump and it went away. Took the pump apart and found the contact points burned and pitted. Cleaned them up and put it back together. Went for a ride and it quit again. Apparently it's been dying for lack of fuel when the pump quits; cycling the kill switch will bring it back for a short time, which is how I got back home. So it's parked till I can get a replacement pump.

 

Part #s are different for MKIs and MKIIs. Anyone know if either will work?

Thanks.

Richard

[Flyinfool]

There is a Mr Gasket replacement from local car parts store that a bunch of people have used that is a lot cheaper than OEM. I do not know the specific P/N.

You can also buy replacement contacts and rebuild the pump.

[flyday58]

Jeff, where would I get the contacts? I don't see a kit on Partzilla where I shop.

[Flyinfool]

Here is the thread I was thinking of.

http://www.venturerider.org/forum/second-generation-venture-tech-talk/87556-fuel-pump.html

This was for a 2nd gen, Now I am not sure if the same pump and parts apply to your 83.

[Neil86]

The points sticking definitely would stop fuel pumping...but judging by the symptoms of low voltage there may be a second issue.

 

Normally on the Venture, power is shut off to fuel pump after 3 seconds or so with no crank rotation detected. If this does not happen and the points are sticking current will continue flowing through them and could burn them worse. You might want to test at the fuel pump connector to see that with key on, kill switch on, power stops after a few seconds with engine at rest.

[flyday58]

The points sticking definitely would stop fuel pumping...but judging by the symptoms of low voltage there may be a second issue.

 

Normally on the Venture, power is shut off to fuel pump after 3 seconds or so with no crank rotation detected. If this does not happen and the points are sticking current will continue flowing through them and could burn them worse. You might want to test at the fuel pump connector to see that with key on, kill switch on, power stops after a few seconds with engine at rest.

Did that before bothering everyone. But what detects rotation, the TCI? I'm pretty good with electricity but so much when it comes to p.f.m. boxes like the TCI. Electrons just disappear in and appear elsewhere. Pure flippin magic.

[Neil86]

Okay...theres a little chain of events.

The pickup coils report crank position and therefore movement to TCI....the TCI shuts down coil firing if engine is not rotating.

 

You have a fuel pump control unit that has a timer and also #2 coil ground wired in....if #2 coil is not firing the timer times down for a few seconds and then causes the fuel pump relay to open, shutting power off to pump points.

 

The timer allows for brief fuel pump operation to top off the carbs with fuel before cranking.

 

The strategy is to prevent fuel pumping for very long when there should be zero demand (engine not running) so a fuel leak or bad float valve will not be supplied with pump pressure.

[flyday58]

Great description, eh? Thanks!

[bongobobny]

Without rereading the whole thread, if cycling the kill switch fixes stuff, then I would suggest polishing up the kill switch contacts as they have been known to cause weird problems...

[flyday58]

Got hard failure now. Put new points in the fuel pump but had to 'adjust' them to get the pump to work right. Started the bike, ran about 3 minutes then quit. Tried a couple times and it started up again, but only ran about a minute. Kept repeating this, each wait time lasting longer and each run cycle lasting shorter. Last time ran less than 10 seconds then quit and refused to start.

 

So started chasing wires again. Pulled a bunch of wire ends from plugs, cleaned a bunch of crud out of same. I have 12v going into the TCI, 12v coming out to the coils, checked side stand switch and relay, cutout relay, tipover relay, pickup coils, kill switch cleaned, checked all grounds, removed, cleaned and reinstalled the loom ground on the left side of the frame, checked continuity on all these wires mentioned.

 

I pulled the bundle apart and checked the splices I did at the large TCI plug on the gray and the black wires. Figured that HAD to be the problem but no dice. Both have good splices and ohm out good, even when wiggling them.

 

Almost every time it quit I was fooling with the 2 TCI plugs so spent alot of time going over those connections, but never got it to start back up no matter how much I wiggled, yanked and twisted them.

 

So what have I missed? I'm thinking about removing the stator cover since I haven't been in there since I got the bike, but all that stuff checks fine. The ground is good and the coils are between 115 and 120Ω. Is there something on the back of the gauges, or a hidden ground I'm missing? I dearly wish I had a spare TCI to try but I don't. Also I'd be flabbergasted if the new Ignitech unit is bad.

 

Again, when it quits it's like you hit the kill switch, only the starter still turns.

 

One more thing, the last time it quit I had my eye on the tach. I wouldn't swear it dropped to 0 first, but it seemed like it did.

Richard

[MiCarl]

Your problem now sounds like fuel. Are you sure that pump is working? Open a carb drain and see.

[Flyinfool]

Open the drain screw on one of the carbs.

When you turn on the key does the fuel pump click?

If not, if you hot wire the pump does it run?

[Neil86]

If you can, retest pickup coil resistance with engine at normal op temp. There have been cases where they test fine cold but go open when at operating temperature.

 

Because the temp is warmer, it will typically test higher on the resistance than the book spec but should be even across all 4 pickup coils.

Edited February 1, 2015 by Neil86

[flyday58]

Pump is working, carbs are full.Won't run long enough to get up to operating temp.

 

Before the hard failure I did a test to see what the symptoms are for fuel starvation. It starts surging as the fuel runs out and eventually sputters and dies after about a minute and a half. It tries to fire off if you hit the starter but won't run because not enough fuel remains.

 

I checked the ignition with a spare new spark plug, no spark. Battery on charger, 12.5v. So I have power to the TCI, power to the coils, but no spark.

[Neil86]

The black you spliced is the main ground from the TCI.....it can have continuity but be unable to carry the full current from the igntion system....heating up and dropping current more etc etc till TCI shuts down.

Try to test the TCI voltage while its briefly running versus the black to see if theres a grounding issue. You might have normal voltage

to TCI vs the battery negative but be low tested against the black wire (before the splice).

[flyday58]

Thanks for the ideas, Neil. Went ahead and replaced the splice. I have good pliers now (Thanks to skydoc_17 for that) so I know the splice is good on the black wire. Was able to get the engine up to temp and checked the pickup coils, got 130, 130, 130, and 126. Across the red/white and black wires I get 13.2v vs 13.8v across the battery. TCI regulating the voltage down to 13.2 maybe? Also get 13.2v on the r/w wire at the #2 spark plug coil.

 

The only way I've been able to get it to run is to put the TCI in the freezer for a few minutes, then it fires back up. I'm down to the Ignitech because I can't find anything else. Has anyone ever had to return one?

Edited February 1, 2015 by flyday58

[Neil86]

When you say you have to put TCI in freezer to get it to run, do this include the initial start today...or after it quit the first time.

[flyday58]

When you say you have to put TCI in freezer to get it to run, do this include the initial start today...or after it quit the first time.

After it quit the first time. When I go out in the morning it will start, but it only runs about 5 minutes before quitting. Thought maybe as it heated up internal connections were breaking. Each time I put it in the freezer for 8-10 minutes the bike would fire and run for a couple minutes.

 

Figuring turn about is fair play and proper investigation technique, I heated the TCI up by letting it sit on top of the now-warm engine till it was pretty toasty, but not hot. Now the bike runs and continues to run! Wish to [your chosen deity here] I had an extra TCI to try out. Really can't conceive this one being bad, though.

 

In the downloaded Venture manual modified by Jeff B. (I think. Maybe Dingy?) he added a note on the ops of the various relays saying that a short on the black/white wire will ground out the TCI. I pulled that wire to eliminate it as causal but the bike still quit, so I've ruled out a short on the b/w wire.

 

Guess I'll pull the stator cover tomorrow and poke around in there.

Edited February 1, 2015 by flyday58

[Donvito]

I know you checked but it sounds like a fuel problem I had last year. If your pump is activating when you turn on the ignition, but not when the bike is running, it will run until the carbs are empty and then stall. Have you tried connecting a jumper wire directly to the pump? The pump should only run until the bowls are full and then stop so no danger of overfilling the carbs. Or, you can jump it at the relay. Just a thought.

[mralex714]

Had the same problem with may 86. I eventually disconnected the tip over switch and no more issues.

[flyday58]

Think I found the issue but didn't want to comment till I had a chance to ride it for a decent distance. As I said earlier there was no spark when this happens, I verified it. I also unplugged the fuel pump and let it run till it died. Running out of fuel takes a while, sputtering and surging till it quits. This is sudden and total. Plus verified no spark.

 

Anyway, went back over the plugs for the TCI. I missed cleaning one wire, white with a green stripe, pickup coil #3. A lot of corrosion and what looked like dirt and grease mixed in. Green stuff. Cleaned all that off and the bike ran fine.

 

I pulled the wire out and it wouldn't start, shoved it back in and it started. Did this 3 or 4 times with the same results each time: wire out no start, wire in starts. I don't get it. According to the schematic it's just one pickup coil for one cylinder, don't get why the bike won't fire at all. I pulled the other 3 for comparison; it won't fire with the orange or white with red stripe wire pulled but will with the gray wire pulled. Since the gray wire goes to #2 coil for crank rotation sensing for the fuel pump relay, I figured it would be the problem.

 

I'm in TEXAS till Monday so can't do an extended ride till then, but I'm hoping it's fixed. I left Dingy a pm but he must be out of pocket for a while, was hoping he could tell me about the inner workings of the TCI to help me troubleshoot this thing. Didn't see how the Ignitech could be bad but needed info.

 

I'll update once I get a ride in.

[Neil86]

I would be surprised that the stock TCI is looking at all 4 pickup coils to determine if the engine stopped....as I know of several cases where there is a bad set of pickup coils

(they are in 2 pairs) and it runs on 2 cylinders. Ignitech might have a different strategy...and doesn't Ignitech only use 2 of the pickup coils and the other 2 are jumpered in the harness?

[flyday58]

I would be surprised that the stock TCI is looking at all 4 pickup coils to determine if the engine stopped....as I know of several cases where there is a bad set of pickup coils

(they are in 2 pairs) and it runs on 2 cylinders. Ignitech might have a different strategy...and doesn't Ignitech only use 2 of the pickup coils and the other 2 are jumpered in the harness?

Well, that's exactly the info I'd like to know, where did you find it? If it's in the literature that came with the Ignitech, I didn't see it. Would love to see a schematic for the installation. Or is that why two of the wires on the Ignitech side of the harness are jumpered together? Couldn't figure that one out, either.

 

Richard

[Neil86]

Just from what I've read on the forums...the Ignitech is only using 2 pickup coils probably to allow more engines to use same TCI.

This long thread started by Todd (TVking63) discusses a lot of things about the design.

http://www.venturerider.org/forum/first-generation-venture-tech-talk/40414-aftermarket-tci-available.html

 

It seems odd to me that you would have a dead TCI with anyone of 3 of the 4 pickups unhooked, would have expected only 2 would have any effect on the unit since the others aren't used.

Edited February 6, 2015 by Neil86

[flyday58]

Thanks AGAIN Neil, this is a great article. And thanks to tvking63, wherever you are!

I've actually seen this thread, only the tail end of it. Never went to the beginning. Thanks to MiCarl for the explanation of the "wasted spark" ignition. Learning all kinds of stuff on this forum.