Kawasaki 1100 top end issues

Joined
Dec 6, 2012
Messages
67
hey guys i got an issue. Customer dropped off a Kawasaki 1100 jet ski because it was running rough on top end. I’ve been tearing my hair out trying to figure this thing out. Compression is 105,105,90, CV carbs have been cleaned 3 times now, spark plug wires trimmed back, new fuel lines, new filter, new spark plugs. For some reason when you take it out it only goes to about 6500RPMS and seems to be hitting almost like a rev limiter, thought it was temp sensor so i bypassed it and retested and same thing, if you hold it 1/4 throttle it seems to get up to 7000 or so but once you go more than say half throttle it starts cutting out again. Everything I’ve ever learned tells me fueling issues but i can’t seem to figure out what could be the issue. Is there anyway to test for fuel pressure? Any secret passageways that get plugged up? I’m stumped and the customers getting upset that it’s taking so long. And i also do free diagnostics if the repair is done with me so i’m sick of eating up all this time on this machine. Any help appreciated!!
 

wahlejim

Master Chief Petty Officer
Joined
Jul 23, 2015
Messages
884
Check the oil pump. It may be dishing out too much oil and bogging it down. I believe it is attached to the throttle so bogging down with higher throttle and running better at low throttle makes sense. It is unusual to get to 7000 at 1/4 throttle, at least on my 1100. Go through and adjust the throttle cables and make sure the carbs are synced.

What year machine is it?
 
Joined
Dec 6, 2012
Messages
67
I believe it’s a 1997, at least that’s what he told me and now that you mention it the throttle cable is kinda loose going to the carb like there’s allot of slack, I’ll have to adjust that and see what it does. I had never thought that it could feed enough oil to cause that to happen but we will see
 

wahlejim

Master Chief Petty Officer
Joined
Jul 23, 2015
Messages
884
check the plugs, they will be fouled if there is too much oil. But I would start with the cable adjustment. Beyond that, possible fuel delivery issue. Insects like to build nests in the vent tubes.
 

wahlejim

Master Chief Petty Officer
Joined
Jul 23, 2015
Messages
884
Verify year by the HIN, last 2 digits are year of manufacture, I believe the plate is below the seat at the rear
 

USA_boater

Petty Officer 1st Class
Joined
Jul 31, 2018
Messages
275
Could a reed valve be torn or broken? Maybe that could restrict enough to limit top-end? One time I had a clogged cat on a nissan truck and could not go over 60mph due to the exhaust back pressure. I've had 2 ZXi's and currently an ultra 150 and never seen what you describe but I have seen limited top speed/ rpm when not running on all 3 cylinders...could it be running on 2? Did you change the plugs?
 

wahlejim

Master Chief Petty Officer
Joined
Jul 23, 2015
Messages
884
Pull the plugs and look at them. If it is only running on 2, it will be pretty obvious.
 

Brien S

Seaman
Joined
Nov 30, 2018
Messages
68
I know this a old post, and I'm assuming you got the thing worked out.
97 would have the cdkII carbs. If it has the cv carbs it's 98 or newer. Cv carbs are junk, and a pain to tune. Oil pump is self metering so no cable to the carb. Cable should be adjusted to where it has just a little travel left at full throttle, but still opens the butterfly's 98-100%. It's common for a plug wire that old to fail, and a real pain to change. It's also common for the oil system to seep and fill a carb with oil after a few days. Best to store it with the bow as low as you can get it, and put some check valves in the oil injection lines. Also, the cv carbs will not run right with the choke butterfly's removed or air box with tubes removed.
 

Brien S

Seaman
Joined
Nov 30, 2018
Messages
68
Also, that compression is low, and variance is to much, providing the gauge is good. ideally should be 120.
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,286
I’d think this is a high speed jet issue. Either needing cleaned or adjusted or both. My old ski did the same. Bogged down at full throttle but back off a little and it picks up.
 
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