Engine quit - request for diagnosis assistance

Hey all! Would love some help trying to diagnose what caused my 1100 to stop running last month. Got it back to the garage and haven't had time to dig into it until now.

History: Replaced fuel pump after the OEM pump demonstrated the dreaded "seizing when hot" symptoms a few times over the last couple of years. Replaced with the Airtex unit that goes into the tank and it operated without any issue whatsoever all summer in all conditions. The vacuum valve was bypassed before the pump replacement when I was trouble shooting the OEM pump failure and the vacuum line is plugged with a golf tee. No other relevant history comes to mind to mention...but please ask if it helps point us towards a diagnosis.

What happened: Had been commuting on the bike all week when all of a sudden within a few blocks the motor goes from running fine to running at what felt like partial power. Similar to what would happen when the OEM fuel pump would heat up, but in this case I had a) the replacement pump that had been working fine, b) well over a 1/2 tank of gas and c) the temps were very reasonable (low 80s).

As I noticed the motor power decrease, I was able to pull out of traffic as the motor quit. I was able to get the engine restarted, but only after giving it some choke. Once running I could remove the choke, but any application of throttle would kill the engine. I needed to move it a few blocks to a safe place to park it for awhile, and I was able to do so by keeping the choke on and sparingly applying throttle. Eventually, she wouldn't start at all.

Now that it is back in my garage and she still won't start:

- I can hear the fuel pump when I turn the key on
- I haven't changed the plugs since I've owned it - bought it with 22,000 on it and it now has close to 50,000. So I've purchased a set of Iridium plugs but haven't put them in yet.
- Checked the air filter that I installed earlier this year and it looks fine
- Pulled the battery and put it on a trickle charger since I've run it down a bit with a few starting attempts.

Anyone want to help point me towards where to go next? Better yet, anyone here locally in Indy want to come over and play "fix the bike?" Would especially appreciate that if we start digging into the carbs to check them...that is one place I haven't gone yet on this (or any) bike.

Nathan

What about the fuel filter? Are you getting gas flow from the filter? Where are you in Indy? I might be able to come up and at least help think about it with you for a day. We work the rest of this week, then have the next week off. Any day between Tuesday Nov. 13 - Saturday the 17th.

Gary.

As Jeff said, I'd try to isolate by spraying some starter fluid into the carbs/aircleaner .

If it starts, its a fuel delivery problem.

As stated above, your spark plugs tell a story with all that can go on in the combustion chamber.

Bad Gas? Where did you buy gas the last time?

I'd start with a new filter, and check the golf tee to make sure it's still in place. If it is, remove it and put something a little more permanent in its place.

Thanks guys - I did forget to mention that I have replaced the OEM fuel filter with the glass tube/replaceable cartridge style (can't seem to find the thread where that style was suggested elsewhere here on the forum) and did that last fall, so that is less than a year old. Nevertheless, I'll start there and report back.

Gary - if you are interested/willing to come up next week that would be fantastic. I own my own business and work from home, so at the moment I'm fairly flexible for Tues/Wed/Thur depending on what works best for you...

smunderdog said:

Gary - if you are interested/willing to come up next week that would be fantastic. I own my own business and work from home, so at the moment I'm fairly flexible for Tues/Wed/Thur depending on what works best for you...

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Nathan, I'll watch the weather, and pick a dry day. PM me and we'll work out the when and where. Also how is the hitch working out?

Gary.

Start simple. If the bike started with the choke applied my guess is that it is fuel related. Since it wouldn't run well with any throttle applied I'd say not getting enough or good fuel. Try an additive for the gas and see if it will clear the issue. See if you can check that there is proper fuel pressure and that the new pump is actually still working, new parts can fail. Because the bike is carburated see if there is fuel in all the float bowls, maybe stuck floates.

GreenZR said:

Nathan, I'll watch the weather, and pick a dry day. PM me and we'll work out the when and where. Also how is the hitch working out?

Gary.

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The hitch has been awesome. Have been using it quite a bit all summer - need to get some pics up with the bike rack and bike on it. Will shoot you PM...thanks!

Just sent Gary on his way...he rode up this morning to help. We saw fuel being pumped into the filter when the key was turned on. We pulled the plugs and verified there was spark at each one. We were getting ready to drain the remaining fuel in the tank and replace with new and as he went to disconnect the smallest of the three wire connectors from the top of the fuel pump assembly, it pulled off much easier than he would have anticipated. We pushed it on securely and the bike fired right up...so Gary rode 3 1/2 hours today to push a wire connector more securely. . And have a good breakfast.

Seemed to run fine on a short test ride...going to ride it a bit longer this afternoon to make sure...

Thanks again to all - and especially to Gary for making the trip up! Gotta love the people on this forum!

LOL Gary 'The Pusher'..

Glad to see it was really a non-issue - lots of great folks on the site willing to help out, gotta love it.

Doh!
Glad it worked out and wasn't $$ to replace something.

+1 on helpful folks here!

Just got home....I took the long way. Thanks, Nathan for breakfast! Glad to help out, and really hope that was all it takes to run well again. Looking forward to more rides for breakfast! I have had a Great day!

Looks like about 240 miles round trip today.

Gary.

Almost sounds like the same sort of fix that we had for the CB on Gary's bike this weekend during our ride to/from Moonshine. He was having a really bad problem getting out on his CB at any distance. When we stopped at Merom, IN to see the bluffs, and as we were walking back to our bikes, he noticed something reflecting the sun in a vent hole in the fairing. Sure enough it was the coax cable! It had come disconnected from the CB unit. Right there and then we pulled out some tools and took off the windshield of his 1100 to get to the base unit of his J&M CB, he reconnected the cable and it worked much better. So his fix took a ride to Moonshine, a burger and the long way home.

Yep! I like the easy fix for things. In my picture you can see the coax connector just hanging there waiting to melt against something, glad I noticed it then. 2 great rides in 5 days, life is good!



Gary.

Bike still good after another hour or so of riding...looks like that was likely the issue. Was disconnected just enough to impact the output of the pump so some fuel was flowing, but not enough to keep the engine running?

Great!

GreenZR said:

Yep! I like the easy fix for things. In my picture you can see the coax connector just hanging there waiting to melt against something, glad I noticed it then. 2 great rides in 5 days, life is good!



Gary.

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Finally got the picture to post, had all kinds of trouble with it this time. But you can see the coax connection.

Happy that things worked out for you... sometimes it is the simplest of things.