4 Symptoms To Detect A Bad Reed Valve On Outboard

Often people confuse the bad reed valve symptoms with other engine malfunction symptoms because of the similarity in signs.

Well, this article will help you to understand how to detect bad reed valves without any confusion and explain how to fix that problem:

What Sign You Should Look For To detect Bad Reed Valves?

There are several symptoms to detect when you have bad or faulty reed valves.

However, if the reed valve starts to rapidly backfire through the carb or blowing crank seals out, that is the first sign which directly indicates that you need to inspect the reed valves.

4 Symptoms of A Bad Reed Valve On Outboard:

The symptoms of bad reed valves are usually similar to the below-explained indications:

1. Backfire, Blowing Crankcases or Spitting

If you notice that your engine suddenly started backfiring or one carb started spitting more than standard, that is the earliest possible indication of bad reed valves.

A faulty or damaged reed valve causes spitting from the carb, and when reed valves fail to control the fuel flow and too much fuel flows into the engine to cause the backfires.

Also, sometimes you will notice light blows around the reed edges or blowing the crank seals out.

2. Engine Becomes Idle

Reed valves are responsible for pushing the air through the engine, where the air mixes with the fuel to create enough oxidization for generating power.

However, bad reed valves tend to go through the engine may bounce around for a little bit and eventually disappear, which causes a lack of oxygen in the fuel mix. And as a result, your engine turns into idling motion.

3. Hesitates During Acceleration

If you ever experience that your engine hesitates during acceleration, that’s another clear symptom of having bad reed valves.

As the motor receives an extended fuel flow than usual because of the damaged reed valves, it fails to respond promptly.

4. Lack Of Power & Spark

When you observe that the riding or sailing speed has become noticeably slower or lower than usual, you should check whether the reed valves.

Since bad reed valves tend to reduce the oxygen quantity in the fuel mixture, as a result, fuel draining into the carburetor with no spark to ignite it.

If you set the engine on higher RPM, the power will temporarily go up, but eventually, drop again.

If you ever experience any of these mentioned symptoms, make sure to inspect the reed valves thoroughly to fix the issue.

How To Fix A Bad Reed Valve?

If you detect any of those symptoms mentioned earlier, remember to act calmly but quickly.

Here are the five easy and efficient ways to fix the problem so, let’s learn together-

1. Remove The Carburetor:

To do a proper inspection and access the reed valve screws remove the carburetor first.

Then remove the screws to pull the valve body out and be careful to keep the gasket intact for reuse.

2. Increase The Internal Pulse Port Ways:

You will notice a small port that goes from the reed valve’s crankcase side to the carburetor mounts.

So, carefully increase that port size up to 3.5mm (gasket hole size included) with a #27 bit. It will increase 25% of the passageway’s space and improve the performance of the fuel pump.

Experts also suggest making the internal pulse port passageways oversize. t is open.

3. Examine The Reed Valves:

Now examine the reed valves closely and use a LED flashlight to check whether any reed petals are missing, cracked, chipped, or deformed.

If there is no light leaking from the valve body edge, it means all petals are uniformed and perfect in shape.

If you see light leaking, then fix the petals and flat the cage properly.

4. Inspect & Fix The Closing Force:

If the reed petals have a weak closing force, they will fail to perform efficiently and quickly. Therefore, you need to check and replace the petals if required.

Now use a hand-holdable letter scale and some dental floss to check closing force.

Then use a toothpick to lift a petal and thread one floss piece under the petal lip, through the center slot, the bolt hole, and tie it around the long carburetor bolt.

Make a circle on the floss’s other end and measure the force, whether it is 2mm or less.

Your standard reed valve should be at least 2.5 so, the bottom line is 2 oz, and if the measured size lower than 2, replace the petals.

To replace the petals, use a blue thread lock on the screws to seal the petals securely.

5. Reattach the Reed Valve & Carburetor Again:

Now clean the threaded holes and all reed valve screws properly with a cleaner. Then use a blow dryer to dry them neatly before reattaching the reed valve and carburetor in each position again.

Are Inspect Or Replacing Bad Reed Valves Typically Expensive?

Technically, it mainly depends on the damage level of your engine’s reed valves. If the damage requires some temporary fixing like cleaning clogged space, torquing loose screws, or changing small parts, then it will not cost you a fortune.

Also, if you know how to fix this type of mechanical parts and good at that work, it will save your labor cost to hire an expert.

However, in general, reed valves are not expensive, and if you buy from a good brand the product will worth your investment.

Better to shop and replace from the same dealer you purchased the engine & outboard. In that way, you do not have to worry about the quality and service.

How Often Should You Inspect Bad Reed Valves Outboard?

Generally, you should replace the reed valve petals after each 100 to 150 hours of operation.

The required servicing or inspection may vary based on your engine model and brand.

Therefore, the best idea to avoid messing up with the standard servicing schedule is to check and follow the instruction manual given of your engine.

Final Thoughts

The reed valves are essential to seal, secure and control the proper air-fuel mixture and crankcase compression. Bad reed valves reduce the engine power or speed and cause it to awfully stall, idle, or even die.

Therefore, always maintain the required inspection and servicing of the reed valves according to your engine’s instruction manual.

You Can Also Read:

Similar Posts