Engine is out.

Kiwi Rider said:
Quote . . .What could break while riding that would cause a no start condition?

I would hazard a guess the valve timing has changed due to the chain tensioner failing in some way and the chain has jumped a few teeth.
Perform a compression test on all 4 cyls and I think you'll find inconsistencies on 1 or more cyls.
This is the only scenario I can come up with after considering the symptoms, unburnt fuel detonating in the exhaust headers, engine cranks but won't run.
Remember, it will only store the FI fault codes as long as the ignition is switched on. As soon as you switch off the ignition, codes are wiped.
Click to expand...

Gonna open up a couple covers first, then I will probably pull the valve cover and see what I can see. I will say when cranking it feels as if there isn't any stress on the starter. I can however hear the compression with the spark plug out. But you may be onto something. I was in it full bore at the time.
 
greg3852 said:
Gonna open up a couple covers first, then I will probably pull the valve cover and see what I can see. I will say when cranking it feels as if there isn't any stress on the starter. I can however hear the compression with the spark plug out. But you may be onto something. I was in it full bore at the time.
Click to expand...

You really should remove all the spark plugs and compression test it, or leak down test if you have the test equipment.
It's really important to follow the test procedure when diagnosing problems such as this, and compression test is No. 1 step. If you're taking covers off and visually checking stuff you're stabbing in the dark so to speak.
All I'm trying to stress is to start with a comp. test, you NEED to establish the basics, and the correct compression reading at TDC is paramount when diagnosing faults.
Will be interested to know how it all pans out.
Good luck my friend, it's a bummer when this happens and I've been there, done that, got the t-shirt, unfortunately :confused:
 
Thanks. It's just a matter of time. Going to check compression on the cylinders tonight, but I am leaning towards the crank position sensor.
 
Ran a compression test and got around 145 or so across all cylinders. Was done with all plugs out, throttle bodies on and wot. Seems low but the engine was cold so they are going to be. Was the same across all cylinders so it’s gtg.
I ordered a used cam position sensor that is coming on Saturday just to see. It was $20 so it is worth it to me. I think that or the crank position sensor is the culprit.
 
greg3852 said:
Ran a compression test and got around 145 or so across all cylinders. Was done with all plugs out, throttle bodies on and wot. Seems low but the engine was cold so they are going to be. Was the same across all cylinders so it’s gtg.
I ordered a used cam position sensor that is coming on Saturday just to see. It was $20 so it is worth it to me. I think that or the crank position sensor is the culprit.
Click to expand...
Well that's a relief! I was lookin' at the worst case scenario, so glad to hear the compressions and mechanical side is A-OK!
 
Cranks over okay with the plugs in?
Crank it till you get the FI Light leave the key on. Jumper into dealer mode, read the code
 
Cranks over fine. Using a 24volt system with one new battery and it cranks like crazy. I'll try it when I get home, but I've cranked it till the battery died and it hasn't thrown a code.
 
I tell everyone with a hard starting busa
CHECK YOUR VOLTAGE AT THE COILS WHILE CRANKING
I had the only 24volt 8.5-1 compression Busa on the planet,, and it still cranked and cranked and cranked before maybe finally starting
 
greg3852 said:
Cranks over fine. Using a 24volt system with one new battery and it cranks like crazy. I'll try it when I get home, but I've cranked it till the battery died and it hasn't thrown a code.
Click to expand...
Can’t believe you didn’t order your new sensor through amazon prime to get it delivered the very next day. Just kidding. Lol! I hope she fires up after you replace the sensor on Saturday.
 
mabupa said:
Can’t believe you didn’t order your new sensor through amazon prime to get it delivered the very next day. Just kidding. Lol! I hope she fires up after you replace the sensor on Saturday.
Click to expand...

LOL I always forget about Amazon when I look for bike parts. I don't know why.
 
If the cam sensor was bad you would get a C11 code
Most likely not that, Airbox off cycle key with throttle WOT,,, flashlight,,, do you see fuel? a shot of starting fluid,,,does it fire?
 
Yeah I have one or two around
as well as a pigtail harness to measure the output

Been thru the cam sensor thing
 
202mphbusa said:
If the cam sensor was bad you would get a C11 code
Most likely not that, Airbox off cycle key with throttle WOT,,, flashlight,,, do you see fuel? a shot of starting fluid,,,does it fire?
Click to expand...

In addition, if a cam sensor goes out while you are riding it, nothing would happen except an FI light and it would hit a false rev limiter at around 9,000 rpm. The ECU only uses the cam sensor to determine TDC while starting and as "check" for the rpm. I would guess the cam chain has jumped time...
 
RansomT said:
In addition, if a cam sensor goes out while you are riding it, nothing would happen except an FI light and it would hit a false rev limiter at around 9,000 rpm. The ECU only uses the cam sensor to determine TDC while starting and as "check" for the rpm. I would guess the cam chain has jumped time...
Click to expand...
ohhh poop.... RansonT dropping some knowledge on people.... sounds that way anyhow
 
While riding it threw an Fi light and the rpms dropped then went up and down then I shut it off.

Gonna give that a try before dropping the motor again.
 
You must log in or register to reply here.

Similar threads

J
Possible Engine "Swapportunities" ???????????
Replies
7
Views
2,333
mestona
mestona
E
Engine recommendations
Replies
16
Views
907
202mphbusa
202mphbusa
Busaman5000
How many miles is on your busa?
2
Replies
33
Views
4,065
DocDrop
DocDrop
E
engine cutting out
Replies
9
Views
1,576
chrisjp
chrisjp
B
#RIP to my Busa engine - Advice Needed
Replies
17
Views
3,720
BlackHammer
B
Back
Top