FLHC 1987 shuts off at speed
Thread Starter
|
Novice
Joined: Jun 2021
Posts: 18
Likes: 4
From: Tennessee
FLHC 1987 shuts off at speed
The 1987 FLHC has 64,000 miles on it. The bike sat for many years in my friends garage till he honored me by giving me the bike. The issue is that the bike will run along for maybe 5 miles and will suddenly miss until it shuts down. I coast to the side of the road. I hit the starter and it comes alive and off I go for 40 miles and home. The frequency of occurrence is increasing. Today I took off and in 5 miles this scenario was repeated. During the process of shutting down, I switched the ignition off and back on and hit the starter. Nothing. Bike is in 5th gear and decelerating I twisted the grip three times and hit start. It tried to start and sputtered and died. I stopped. Tried to start and it attempted to but would not. I changed spark plugs (rear one was sooty and front one light brown) and it started and off I went home. Almost didn't make it as the process of stalling started again. It feels like its not getting gas but it has a new CV carb. that is brand new only two weeks ago and it is jetted properly. The following is what was done to the bike when I got it: New CV carb, fuel filter in line, new fuel line, gas tank was removed, cleaned, sealed with Ceem and a new pet **** installed. Battery is new. Terminals are tight. I do use premium gas. New plug wires. I am suspecting the coil pack because I have run this bike 60 miles already and no occurrence then, last week ran 6 miles and it did it on way back. Today same. Getting harder to start each occurrence. Sorry this is so long. Thats the story. But when I blip the throttle during shut down, it tries to fire up. That's messin with my head.
The following parts will be installed on this Thursday: New coil pack and new ignition module. Appreciate any ideas. I'm not good on Harleys but love this bike. Had lots of air head BMW's thought. This Harley is wonderful when she's runnin well.
The following parts will be installed on this Thursday: New coil pack and new ignition module. Appreciate any ideas. I'm not good on Harleys but love this bike. Had lots of air head BMW's thought. This Harley is wonderful when she's runnin well.
Last edited by Gary.Loucks; Jun 27, 2021 at 11:18 AM.
Grand HDF Member
Joined: Jan 2006
Posts: 4,205
Likes: 1,192
From: Anywhere we stop
Have you checked the petcock screen, have you done a flow test on it? If that's clogged it will starve the carb. After it sits for a bit the bowl fills back up and it runs again.
Thread Starter
|
Novice
Joined: Jun 2021
Posts: 18
Likes: 4
From: Tennessee
Engine shut off
Yes took fuel line loose from tank. Its wide open flow
HDF Community Team
Joined: Dec 2005
Posts: 5,428
Likes: 2,623
From: NC USA
Most often, modules totally die when they go bad. The timing sensor will give intermittent problems but I'd try coil first, timing sensor next.
To check module - unhook the timing sensor from the module at the connector (on the right downtube). Put a spark plug on a plug wire and lay it on the engine. Switch on - short across the green and black wires at that connector on the module harness. When you break the connection you should hear and see a strong spark. If not, suspect module. There's more tests but that will tell you if it's shot. If good then test timing sensor with an ohm meter.
To test sensor - with ohm meter set to 1 ohm or continuity. Check red pin to ground. Should be no continuity. Reverse test leads and result should be the same.
Put red test lead to the green wire socket and black test lead to black wire socket. Should be no continuity.
Reverse the test leads (red test to black wire, black test to green wire) should read 300 - 750k ohms. If not reading, sensor bad.
Ohm test a coil will only tell you if it's open (bad). If it reads good, doesn't mean it will fire. But it should read 2.5 - 3.1 across the terminals and 11k - 13k across the output towers.
To check module - unhook the timing sensor from the module at the connector (on the right downtube). Put a spark plug on a plug wire and lay it on the engine. Switch on - short across the green and black wires at that connector on the module harness. When you break the connection you should hear and see a strong spark. If not, suspect module. There's more tests but that will tell you if it's shot. If good then test timing sensor with an ohm meter.
To test sensor - with ohm meter set to 1 ohm or continuity. Check red pin to ground. Should be no continuity. Reverse test leads and result should be the same.
Put red test lead to the green wire socket and black test lead to black wire socket. Should be no continuity.
Reverse the test leads (red test to black wire, black test to green wire) should read 300 - 750k ohms. If not reading, sensor bad.
Ohm test a coil will only tell you if it's open (bad). If it reads good, doesn't mean it will fire. But it should read 2.5 - 3.1 across the terminals and 11k - 13k across the output towers.
HDF Community Team
Joined: Dec 2005
Posts: 5,428
Likes: 2,623
From: NC USA
I should have pointed out, often an ignition problem on these is simple as corroded connections, especially at the breakers. You can access them by taking the headlight assembly out. Never a waste of time to clean the breaker terminals and wire ends, or clean the wires and replace the breakers. Ignition is the second from the right as you're looking into the fairing from front of bike... if memory serves me.
Trending Topics
Thread Starter
|
Novice
Joined: Jun 2021
Posts: 18
Likes: 4
From: Tennessee
1987 flhc
Great information! I appreciate it very much. Only thing I didn't order was the pickup. This is a great site. Wonderful! Thanks.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
Road Warrior
Joined: Dec 2012
Posts: 1,539
Likes: 692
From: magnolia tx
Could be an ignition or coil going out problem but typically the bike will not start right back up they have too cool some first, you said the bike has been sitting around, is there rust in the gas tank?, also I do not like to use an inline filter in a gravity feed system, also you can try to loosen up the gas cap it maybe bad and not venting, also check float height is correct, float needle valve for trash or sticking, check your grounds all your grounds on the bike including grounds for ignition module
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,201
Likes: 3,089
From: NW AR
I had a problem with my bike years ago. It would just totally cut out on me at speed on the highway. I'd pull over and it would kick off and I'd ride on. Happened very intermittently. One day, it hit me on the NW side if Houston, died on the highway, I managed to coast to an off ramp and into a hotel parking lot. This time it would not restart. Dead. I had a spare module with me, which I swapped out and it still wouldn't start. Linda was with me on her bike. I left her in the hotel bar, took her bike home to the other (SW ) side of Houston, got the truck and the loading 2x12 board and went back. By then Linda had, as usual, made a whole slew of new friends who came out and helped me load the bike up into the truck. Turned out to be one of the wires from the pickup, after it exits the hole in the cone and heads to the frame was broken INSIDE the insulation where you would never find it. Rubber mounted motor vibrating over the years flexed that wire and it broke. At least I found the problem I'd been chasing for years.
