Experinced mechanic stumped. (998 wont start)

3136 Views 15 Replies 5 Participants Last post by ducati888916, Nov 6, 2014

Hurricane Racing

Discussion Starter · Sep 4, 2014 (Edited)

Ive been working and building my own ducs for over a decade now, and this is my first 4 valve. And here is whats happing. turn key to on and fuel pump primes, All gauge lights are working proper, The batt has lots of juce and cranks as hard as hard as ever. (the batt is 9 months old). The choke dosent seem to make a diff. And when I statred it up last week everything was fine. cranked up in 2 seconds.
And before I put it up I I let it get up to 160-175 temp and blip it a few times and then shut it off.

Please help
Jay

Thank you

1 - 16 of 16 Posts

Hurricane Racing

Discussion Starter · #2 · Sep 5, 2014

I think I have it down to bad spark plugs, and perhaps I flooded the motor when trying to start it.... what do you think?

widewalker

· #3 · Sep 5, 2014

Sounds very possible, especially if you have irridium plugs in. I have had a few episodes with fouling plugs on my 998. Stock plugs seem best. Take the plugs out, let it dry out for a bit and put new stock ones in.

tye1138

· #4 · Sep 5, 2014

Maybe…

Hurricane Racing

Discussion Starter · #5 · Sep 5, 2014 (Edited)

like i said this is my first 4V and a have less then 2k mi on it, also my first fuel injection.

I am working with a broken leg right now,, i have it on the batt tender and i was thinking a bout shooting a quick 1-2 secont shot of starting fluid... whats your thoughts on that.

ps i have no idea what plugs it has, can i pull them and check them with ease?

thx

THE SIMPLEST THINGS!!!! lol

I have been down with a broke foot for 2 months now and I have been starting it up about once every 10 days and i guess thats what fouled the plugs...

a touch of ether to the open air box and its ALIVE!!!! ALIVE !!! lol

thanks

Any Idea how to keep this from happing agen?

See less See more

tye1138

· #6 · Sep 5, 2014

Hurricane Racing said:
Any Idea how to keep this from happing agen?

Don't open the throttle when starting a fuel injected bike.

The system will easy flood and then you'll be stuck with wet plug syndrome.

Hurricane Racing

Discussion Starter · #7 · Sep 5, 2014

except for that one time I never do. it was just as was cranking it i herd it start to show the smallest signs of life and as I cracked the throttle it woke it up.

Other then that I never do and will try to never let it get like that agen.

Also I let it warm up to about 160-170 degrees and steddley revved it to about 5k to 3k for about 40 seconds and then quickley shut it off hopeing not to allow anything to cause a plug foul... was that a good idea?

tye1138

· #8 · Sep 5, 2014

Something is wrong for sure. But you gotta keep running it and see what happens. Maybe the "blip" simply went away? IDK mate, doesn't sound right to me. More information will be necessary about the bikes background, maintenance schedule, etc.

Hurricane Racing

Discussion Starter · #9 · Sep 5, 2014

I bought it from a idiot who dident know his ear hole from his ass hole. but with the price and to know it wasent stolen ... I couldent pass it up.

widewalker

· #10 · Sep 6, 2014

BTW, the "choke" you mentioned in your fist post is not a choke, it is a "fast idle" device. don't use it to start the bike but maybe to warm it after starting. No throttle when starting...nothing...just press the start button.

Hurricane Racing

Discussion Starter · #11 · Sep 6, 2014

tye1138 said:
Something is wrong for sure. But you gotta keep running it and see what happens. Maybe the "blip" simply went away? IDK mate, doesn't sound right to me. More information will be necessary about the bikes background, maintenance schedule, etc.

I dont see how a problem like that could happen overnight.

"BTW, the "choke" you mentioned in your fist post is not a choke, it is a "fast idle" device. don't use it to start the bike but maybe to warm it after starting. No throttle when starting...nothing...just press the start button."

I rember that and do just that. 3-7 seconds depending if it is 70 degrees or 50 degrees. nothing more.

tye1138

· #12 · Sep 6, 2014

You don't really need the fast idle anyway, its there for super cold days.

Yea, the bike probably needs a going through. Have you measured compression? Low compression can cause plugs to foul as the combustion process doesn't burn all the fuel off.

Hurricane Racing

Discussion Starter · #13 · Sep 6, 2014

tye1138 said:
You don't really need the fast idle anyway, its there for super cold days.

Yea, the bike probably needs a going through. Have you measured compression? Low compression can cause plugs to foul as the combustion process doesn't burn all the fuel off.

How bad can the compression be if the bike will do 170mph... (the stupidO I bought the bike from said it had just had a full valve & belt and fluid service about 1k mi before I bought it. (no records) the mi at time of perches was 15k mi.

Let me repeat that when I would start it up to ride it (even if it sat 3 weeks + ) it would start in 2 seconds and be just fine. But now that im injured and have been so for 2-3 months now, its getting slightly harder to fire. I think this is due to low rpm foul plugs...?)

Slower than you

· #14 · Sep 9, 2014 (Edited)

Sounds like stale gas that wouldn't light off. The ether helped volatility and showed no real problem with the bike.
Dump the gas into your car and put fresh stuff in the bike and you should be good to go.

Just a FYI, the 998 computer has to count about 10 engine revolutions when you hit the starter button, then it allows fuel and ignition to flow and it lights off. As mentioned, don't open the throttle when cranking, just leave it at idle.

Here's another little tidbit. The immobilizer will shut off fuel and ignition if you leave the key on for 10 seconds without cranking it. Push the button after 10 seconds and it'll crank till the starter fries or the battery dies to no joy. Key off then back on and it'll start.

Hurricane Racing

Discussion Starter · #15 · Sep 9, 2014

Ive been busted up with a cast on my leg for 2 months now and I know 3 months is max on gas so Im going to take it out with the cast and all and clear that bitch out. (sound good? ) I NEED TO RIDE!!!!

ducati888916

· #16 · Nov 6, 2014

I had a 998 that was very hard to start. It was a race bike that was converted from a crashed road bike. There was loom trouble, which we traced and fixed to get it running initially. I rode it for a while, then blew a piston. It sat for nearly two years completely stripped and we eventually got around to fixing the engine. It initially gave a lot of trouble starting from cold, but I replaced the plugs, battery and went through the wiring again, as well as replaced the ECU and away she went, but unfortunately threw a rod.

We fixed it straight away (within 6 weeks) and from that point on it was a bastard to start from cold. Didn't matter what I did, it just wouldn't start. Eventually I'd have to jump it from the car, over and over until it got warm enough to start.

When it was running, it was a rocketship, flawless on the track, heaps of power, etc. Once it had been running, I had no more trouble starting it again the same day. But come the next morning, ready for race warm up - nope. Wouldn't start.

I replaced the battery cables, entire loom, tested injectors, changed the fuel filter, coils, pretty much everything that could be measured, tuned or changed was changed.

Nothing helped. It remained to be a bastard haunted dog of a thing. I believe there is a fundamental flaw in the 998 ECU and wiring that wasn't present in the 999 with the CAN BUS active on the ECU. I eventually sold the bike in disgust.

My. Worst. Ducati. Ever. And it wasn't much faster than the 996 race bike I replaced it with, which was the Best. Ducati. Ever.

See less See more

1 - 16 of 16 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.