New Engine - Yay! Won't Start - Boo!

OK XJ gurus my blown original engine has been replaced with a gently used engine (38,000km) but it will not start. Every system was working well before the bottom end dropped out.

Tons of battery power (20A Battery) that has the starter ripping no problem. All connections solid. Full of new oil, etc. The only thing I can think of is the ignition pickup assembly. This is one part I wanted to switch out with my old one because I knew it worked well. However, 2-broken Allen keys later, I decided to stick with what came on the engine. Compression is 160-170 across the cylinders and there is fuel getting to the cylinders.

Any other suggestions other than the ignition pickup?

 

Did you do any testing on the pickups?

 

Nope - couldn't get them out anyway. I will search the forums for testing procedure and see where that leads.

 

It's in the manual. You unplug the connector from the TCI and get an Ohm reading across them. The value escapes me right now but I did it just the other night.

 

Great, thanks for the info. I was just about ready to give it away after all the effort today in the heat and humidity. Spent all that money, sweated off about 20 pounds, took a day away from work, and then to have her not go...

OK, next chance won't be for a few days. Hope the ignition pickup is the problem.

 

So i'm going to assume you've checked for spark on all 4 jugs and found none?

 

Yup and there be nada. No spark at all.

 

You should have drilled those screws out and collected the old Pickups.
You don't have to be kind to a blown engine.

OK. You got compression.
Now we need:
Spark - Fuel - Air

Double checks:
Coils plugged-in and grounded.
Engine Ground Strap
Pick-up Coils Plugged-into Harness
Fuses

The Pickup Coils:
Resistance: [ 120 Ohms +/- 10% at 20-Deg. C 68-Deg. F ]

 

check the pick up coils, plugs out, ign' on, pass a knife blade betweew the pick up & rotor, you should get a spark at the plugs.

 

Super fellas, appreciate the details you provide.

Rick, the rotor retaining bolt in the new engine is the culprit here. As the connection for the pickup assembly was crushed by the wrecker, it was even more incentive to swap it out. In attempting to remove the bolt, 2-good Allen keys bit the dust and a third is badly bent but usable. So I was forced to repair the harness by splicing old and new, which was done with solder, shrink tubing (great stuff that tubing!) and cursing. Should WD40 plus a new quality 6mm hex key socket do the trick and get the bolt loose, then there will be more cutting, splicing & cursing and hoping that I won't ruin the pickup harness in the process.

The possibility of snapping the bolt off scares me more than anything.

 

OK, so after testing the pickup and finding it faulty, i swapped in the old one (it pays to have the right tool - the retaining bolt for the rotor came loose immediately) and shazam, it started right away, responded to throttle. Then stopped and would not restart. In case it was flooded, it was left alone for a half-hour and then tried with no result. What gives now? Yes, the tank is full of gas.

These issues are so hard to diagnose, but anything from you guys is appreciated. I can find no grounds, bare or loose wiring, etc.

So close, so far...

 

check all the fuses again.

 

I did something wrong, last week.
I ain't got it figured-out yet.
Rode the 900 home from a job.
Purring.
Got a TCI to test on my bike in the mail.
Ran my bike to warm it up a bit.
Killed it.
Un-plugged MY TCI ... anchored to Plastic panel.
Plugged-in the TCI to test.
Bike ran for 10 seconds or less OK ... began to stumble ... then, died.
No re-start on the test TCI.
Hooked-back-up MY TCI ... Rough Idle ... 3-Hole Intermittent.

Borrowed a Shop's Test TCI ... Bike purrs again. Panels and systems all Green.

Go figure???
What the difference between getting +12V when the Ign is turned-on and getting +12V getting plugged-in.

 

So, Rick you're thinking TCI? Did I also read elsewhere that you provide a TCI service? I'll try the fuses and review the connections, but the TCI seems to make sense given the circumstances....

 

This morning on a whim I went out and gave it a try. VROOOOM!

What I thought was a response to throttle last night was not that at all. Didn't have my hand on the throttle this morning and had same result. Here's what happened - small choke, turn key, turn switch, hit started button, VROOOOM, died, won't restart.

Could this be a TCI issue? What are other possibilities?

 

What's happening is that when it starts, it's almost like it's unthrottled - goes to about 4000rpm for a few seconds (sounds wonderful) and then shuts off, not to be re-started.

Any advice appreciated fellows.

 

So, home for lunch and I gave it a spin and paying more attention this time, it went to 6,000+ then I killed it. Hit the button again and away she went, hit the kill. Hit it again and away it went, hit the kill.

What the hell? At least it's starting. After some poking, I decided to pull the tank. relieve the choke cable of its mounting perch on the carb rack. connected the tank, hit the button and she started and idled perfectly. It was the choke! However, after letting it warm, response to throttle caused a stall. Let it run for ten minutes and the result is the same.

So, questions for you guys:
-Why is the choke mount affecting the operation, as it didn't on the other engine, same carbs, etc? Seems like I need to slacken the cable, but with 3 adjusters on the linkage, I do not know what to do, scared to screw something up.
-Why will a warmed engine have poor throttle response and not run to 4000rpm? Carbs were treated gently between ins and outs.

 

Man, do I feel like a stupid idiot. I've had the engine in and out 4 times now and never did this stupid thing. So as an update, she runs and runs fine, starts every time and seems to work well. May have to do some YICS work but that will be a lot later after I get a few miles on the newer mill. The pickup change fixed the starting issue and the stupid thing I did caused the secondary issue of starting, revving, dying and not restarting.

There is a new thread started, keyed off the "What Did You Do to Your Yamaha Today" thread. This may or may not help anyone but it could prove to be fun. Besides, now I can prove to my wife that I really DO admit when I'm wrong and do dumb things.

 

I'm not the TCI man.
The other Moderator ... "Robert" restores TCI's.

If you h ave been-over all the other possibilities ... what would it hurt to Test the Bike on another TCI.

I think in my case I might have done something to the TCI because I didn't have the Ignition turned off while making a swap.

You lose the whole load. That would make me troubleshoot the Ignition Circuit for an OPEN spot in the Circuit.

Fuse Panel
Ignition Switch
Pull the Connection Pigtail to the Ign Switch and ck for 12V
If I found 12V Hot at the Ign ... I might try jumpering the Ign Circuit and giving that a Teat to Isolate the Ign Switch.

You need a "Y" Jumper to connect 3 wires at the Ign. Pigtail.