GPZ1100 with Old-Styl DFI Won't Start When Hot

Based on what I read tonight, it sure sounds to me like the Dyna is what's causing the hot start problem.

You don't need any grease or anything else between the Dyna plate and the ignition housing. The best ignition for that bike was the OEM CDI. Find one of those...toss that POS Dyna and ride into the sunset smiling and happy.....

The only time I would ever replace a factory ignition with a Dyna, on the street, is if it's an old KZ with points.... OEM ignition on the CDI equipped KZ's is very good stuff.

People that sell Dyna will tell you different. People that really know these old bikes will tell you the truth

JMO

Larry C

You'd have to find a set of pick up (Pulsing coils). Checking with Kawasaki.com website has determined that the Pick up(pulsing) coils are available . The pulsing coil # is 59026-1133 and replaces the older # 1002, 1012 which were used from the MKII motors until the 2005 P24.

The resident "Wizard" here "Loudhvx" has made up a IC Igniter replacement using off the shelf GM Ignition parts. He's used it on his GPz550 for a number of years. So if you want to go back to what your bike had for the Kawasaki supplied ignition, you can.

Everyone:

I went for two rides tonight, first ride with the ignition cover on. Came home, and no suprise, it cranked, but would not start again until it cooled. After it cooled, I removed the cover off and took it on another high-speed run, came home and shut it off and waited ten minutes and tried to start it. Didn't start this time, but after another five (for a total of fifteen minutes of cooling), it started, but ran a little rough - no purring.

I did take number one spark plug out after it didn't start right away after the second ride. I had a little difficulty getting a good ground on it, but when I cranked the engine, there was spark, albeit not a good blue one, but white with a little yellow thrown in. The plug was dry, but black and not tan colored. I proceeded to take out number four spark plug, but didn't check the spark beforehand. However, I noted two things about the condition of the spark plug. One it was not black, but beige, maybe more white colored, and two, the little metal cap on the top of the spark plug had un-threaded itself from the top of the plug. I found that on the ground when I went to put the spark plug boot back on. Fixed it, then put the spark plug's boot back on.

Did find something else of interest too. Before my second ride, I swapped back my original air flow meter (sits between airbox and filter). When I was in the process of swapping the air flow meters, pulling one out and putting the other one into the rubber ring (air flow meter's seal) on the back of the airbox, I noted a pretty loose fit between the rubber seal/ring and the circular mating surface of the airflow meter. Early in the season while going through everything with a fine-tooth comb, and trying to determine why the bike wouldn't run (one, a bad ignition coil, and two, the big one, a rusty fuel tank), I wrapped a narrow strip of packing tape around the air flow meter's mating surface a couple of times to "tighten up" the connection then. From what I've seen tonight, it's much looser, even with the tape wrapped around it.

From a website that I gleaned from an old reply of Motor Head's to someone else experiencing DFI problems, I was able to get a lot of information regarding my Bosch L-Jetronic fuel injection system. Between what I read on that website and what I infer from the factory service manual, is that the system is really sensitive to air leaks. Therefore, I'll make it a point to tighten up the loose fit between air flow meter's snout and its seal on the back of the airbox. I'm wondering if perhaps, this loose fit between the airflow meter's snout and its seal on the airbox is contributing or causing the hard/no start when hot. Perhaps when the engine cools sufficiently, the engine temperature sensor sends a strong enough feedback signal to the ECU to richen the air/fuel mixture enough to start the engine, but doesn't do so, if the engine is really hot right after shutting down. Regardless, I need to tighten up that airbox seal some way to a) stop un-fitered air from getting sucked by it, and b) perhaps fix or improve the problem that I'm experiencing today. I guess a little shot of ether into the airbox might reveal the mixture being to lean to start. Comments?

However, a loose fit between the air flow meter's snout and its seal didn't seem to affect it the other night when I rode the bike with the ignition cover off, and it started up okay after sitting ten minutes. Or maybe that was just a fluke.

If anyone knows what (the looseness between the air flow meter's snout and its seal) I'm talking about, and knows a fix for it, please don't hold back. Believe me, I've tried to locate a new airbox seal, and can't find one.

Still looking for suggestions on my hard starting issue and possible causes and the fix.

Thanks to all again.

Larry:

When I found one bad Kawasaki ignition coil last fall, I tossed them both, reasoning from what I had read, that they weren't all that great when they're 30 years old, and the other one probably wasn't too far behind the bad one.

Buying the "green" Dyna coils was the first try at a fix for the bike not wanting to run. I really thought that I nailed that one when I found the bad coil. But in hindsight, most, if not all of my running, or lack thereof, problems were coming from rust in the gas tank. That thing looked clean when I looked down the neck of it when I was going to buy the bike, but the rust was lurking on the bottom flat surfaces out of sight. Rustol, did the trick on that problem, of course after a lot of grief - and money!

When I replaced the original coils with the Dyna greens, I said to heck with the old ignition system, and decided to go all Dynatek. However, I did keep all of the rest of the original Kawasaki ignition components. Igniter, and the pickup coils with their mounting plate. I guess I could re-install the old igniter and pickup coils' assembly and see what that does, but I'm not sure if the Dyna green coils are a match for the old ignition system. I think they are though, anyone want to chime in?

Mike, thanks for the pickup coils' Kawasaki part numbers, much appreciated.

Thanks again for the feedback.

Marty

Got some pictures of the Airflow sensor and the connecting boot? There are several cars I can name that have a thin collar of rubber as a seal at the throttle body and or airbox. The Ford Rangers/ Mazda B-4000 with the 4.0 V6 has this. It would fill up some of the looseness you talk about. A good seal here is needed or the Air flow meter flapper door will not be in the proper range. It will be lean.
Those plugs really should be the same color, or real close. The black one, start with the basics, compression. Then Spark, and then even though you had them serviced the injector could be an Issue. You can pull them and check the spray pattern, and see if they leak/ drip. If you saw some of those other threads you would have seen this.
I think the Grey Dyna coils are the 2.2 Ohm which would match up with the stock Kaw ignition.

Most riders are using the green 3 ohm Dyna ignition coils,others have been with the 2.2 ohm Gray(Grey?) coils. Were there any resistors near the old set of original ignition coils? Kawasaki did this on some of the bikes.

I took this out of my Kawasaki shop manual:

Primary(small wires) side of the coils will read between 1.8 to 3.0 ohms.

Secondary(sparkplug wire ports)side of the coil will read between 10.4K to 15.6K ohms. These ports are wired together, so it makes no difference which is used, as long as the correct coil to sparkplug configuration is followed.

The sparkplug caps should read 5K OHMS, any higher, or a reading of infinity means new caps should be ordered.

Everyone:

Took my bike apart today, to get at the cams. I will be swapping out my original cams and replacing them with ones from an '84 GPZ. I found two valves at their minimum clearance, and will be ordering shims for those. Plan on installing a Bosch adjustable fuel pressure regulator in place of the stocker, to boost the fuel pressure at and off idle. Does anyone have any guidelines for these new pressures? Stock is 33 PSI at idle, 36 PSI at off idle.

Motor Head, below are pics of the air flow meter snout to air box opening seal. Here's some info on the seal and its interfaces maybe the one your talking about from a Ford Ranger is close match...

Air Box hole DIA that the seal fits into is 3.214"

Air flow meter's snout DIA is 2.75"

Air box thickness is .17"

Seal thickness is .70"

Seal OD is: 3.48"

Seal ID installed is 2.65"

Marty

GPZ1100_Rider wrote: Everyone:

Took my bike apart today, to get at the cams. I will be swapping out my original cams and replacing them with ones from an '84 GPZ. I found two valves at their minimum clearance, and will be ordering shims for those. Plan on installing a Bosch adjustable fuel pressure regulator in place of the stocker, to boost the fuel pressure at and off idle. Does anyone have any guidelines for these new pressures? Stock is 33 PSI at idle, 36 PSI at off idle.

Motor Head, below are pics of the air flow meter snout to air box opening seal. Here's some info on the seal and its interfaces maybe the one your talking about from a Ford Ranger is close match...

Air Box hole DIA that the seal fits into is 3.214"

Air flow meter's snout DIA is 2.75"

Air box thickness is .17"

Seal thickness is .70"

Seal OD is: 3.48"

Seal ID installed is 2.65"

Marty

Kawasaki always told us to set the valves at the max loose clearance with the lobe pointing directly away from the bucket. I've done them that way for decades. Works just fine.

Install the 84 cams, then check the lash again before you swap shims. It may well change on you with another set of cams. You shouldn't need to boos the fuel pressure much. Smart play is to install it, check the pressure, then turn the adjuster bolt exactly 1 flat and see how much the pressure changes. Then you can tune it without having to hook up the gauge all the time.

With a Murray pipe, air box on....we used to run about 38lbs fuel pressure on the DFI systems and adjust the TPS for highest idle, then drop to 1100 with the main idle knob.

Dyna coils will work with the stock pickup coils providing they are the correct resistance. Hope you have good success with the OEM pickup coils

All:

Put the new cams in, and it looks like it may have been clearances that were too tight causing the hard-starting when hot. Rode it good and hard a few times, and it starts up after sitting ten minutes or so. Runs like a champ with the higher fuel pressure due to the Bosch adjustable fuel pressure regulator installed. Worth all of the troubles shoe-horning it in.

Thanks to everyone for their advice and feedback.

Marty

The first gen injection that had the injectors mounted on the head and not on the throttle bodies had a problem with the injectors. They would either clog up or sometimes go out when they heated up. This system also did not have the TPS and that caused problems because the adjustments were done by the airflow box. Your best bet is to update to the 82 or later system or switch to carbs.

GPZ1100_Rider wrote: All:

Put the new cams in, and it looks like it may have been clearances that were too tight causing the hard-starting when hot. Rode it good and hard a few times, and it starts up after sitting ten minutes or so. Runs like a champ with the higher fuel pressure due to the Bosch adjustable fuel pressure regulator installed. Worth all of the troubles shoe-horning it in.

Thanks to everyone for their advice and feedback.

Marty

Good to here that the bike is running great. Now to get out and ride,