Chance of Engine Hydrolock Due to Carb Flooding

I have an opportunity to buy a 2003 Kawasaki Concours - ZG1000 for a low price, and buy "as is". It will be a project bike since it has not run for the past 4 years. It alledgedly ran OK before being placed into storage. Since the price is so low, I will need to buy "as is" without doing much inspection. The Concourse is a 997 cc. in-line 4 cylinder with 4 CVS32 Keihin carbs. I believe the bike has a vacuum operated petcock. I went to the Concours Owners Group web site and found some discussion about the carbs flooding, draining gasoline down into the cylinders and then hydrolocking when attempting to be started. This apparently can be so severe as to bend a connecting rod. Not good.

I always thought that hydrolock was more common when riding through high water, where it could splash into the intake. And if gasoline got down into a cylinder, then would the starter have enough torque to bend a rod? Now perhaps if the bike was push-started, then that would likely be enough torque to do damage.

My real question is: Just how likely is this hydrolock situation to occur? I found a method of checking the rod length by removing the spark plugs, but I doubt that the seller will allow me to start dismantling things. Anybody have an opinion? Thanks.

Yes, the starter can bend a rod. If you take the plugs out do not turn it over unless it is outside ( think big gisers of nasty fuel). Change the oil and filter before you run it. BTDT

You can't measure the rod length through the plug hole. You can measure the stroke but not the length of the rod.

roy-b-boy-b wrote: You can't measure the rod length through the plug hole. You can measure the stroke but not the length of the rod.

but,
you can check them relative to each other to find a difference which would indicate a possible bent rod,or out of phase crankshaft.

leon

Yeah, like 531blackbanshee said, the piston height for #2 and #3 cylinders should be identical, and #1 and #4 should match. If one cylinder is lower than its mate, then that rod may be bent.

Before buying the bike, I plan on checking the oil level and smelling the oil to see if there is a gasoline odor. And after buying it, I will not crank the engine over until removing the spark plugs. Probably will do the piston height check at that time as well.

I simply cannot see why the Concours engine would be any more likely to flood than the KZ engines, and I do not hear of frequent posts about this happening. It has 4 carbs, with a horizontal air flow, just like the KZ engines. Vacuum petcock, hopefully not left in the prime position. Sure, the hydrolock is a possible problem with grave results, but I am hoping that the probability is low enough that I am not taking too big a chance on the deal.

I think you are worrying too much.

Plan on pulling the carbs and going through them. Measure fuel level, not just adjust float height, to make sure the float needles/seats are sealing properly.

Change the oil and take note if the level is high, which could suggest fuel in the crankcase. Pull the spark plugs and spin over the engine if you want to make 100% sure there is no gas in the cylinders.

A piece of clear vacuum tube for the petcock is useful to make sure raw fuel is not flowing backwards down into the engine. Replace the tube with a normal vacuum tube after the test (unless the clear tubing is fuel safe).

Don't worry, just work smart.

This is a common and serious problem in the ZRX 1100 and 1200. There is a small o-ring inside the petcock that fails and allows fuel to fill the engine block, cylinders, etc. (It's basically the same motor) We use a manual petcock to get around the issue. You must remember to turn the fuel off and on, though. If I still had a vacuum petcock, I would replace the O-RING and have a few spares....They'll last about 2 seasons. The one that fails is the one on the slide that is affixed to the diaphragm. If you suspect fuel in a cylinder, DO NOT hit the starter button with the spark plugs in it! Look at the oil level. It should not be high. If it's high, some fuel has gotten into the block. DO NOT run the engine with fuel in the oil. You can find petcocks on the ZRXOA.COM page. (Good advise here already)

Believe it or not I'm a mod at cog online.org and one of my areas is the C10. The reason the C10 can hydro lock is because the carbs don't have over flow tubes in the bowls and the carbs sit higher than the intake port. A leaky petcock plus a leaky float valve in the carb means gas goes down the intake and into the cylinder. The unknowing hits the starter and since gas doesn't compress a bent rod occurs. There are reports of C10's running for years on a slightly bent rod. There is a fix. Carb bowls from another Kawasaki (I would have to look it up) comes with over flow tubes and there is a guy who can hydro lock proof your carbs plus make the bike just plain run better.

If it is an outside rod that is bent it can be repaired with motor in the bike. Inside rods require motor removal. The rods are paired with letters and there is a guy in the Seattle area who more than likely has the lettered rod one would need.

The C10 can run for a long time. Concours Owners Group has mileage awards. !st is 100000 miles 2nd at 200000 miles and a few 300000 mile stickers have been handed out.

The Concours Owners Group is a good group of guys and gals who have come across about anything that can go wrong with the C10 and are willing to share with out pulling teeth. With the C14 being out since 2008 model year, we are still learning.

To tell you the truth if the C10 is in good shape body wise and it;s cheap enough, a bent rod is worth the trouble IMHO. These are mile eating motorcycles.

And yes, when checking for a bent rod you are checking piston height in relation to the other piston that is at TDC. Center pistons with centers outside with outside.

forum.cog-online.org/index.php

I would also look for rust in the gas tank. And this can be fixed too. Tim

Thanks to 80B4; 531blackbanshee; ZERO; and especially Z1Driver for all the information. I joined the COG the last few days, but only learned of this bike about 4 days ago, so I resorted to the tried and true KZRIDER team, who have been so helpful in the past.
I know I can overcome any problem as far as mechanical ability is concerned. I just want to avoid excess costs and/or extreme labor. Otherwise I might as well just buy a good used bike. Thanks again everyone. I'll let you know how it turns out.