“Clacking” noise on SP 135

[angus99]

"I wonder how to tell if it’s carbon,"

Getting rid of carbon in the cylinder head is simple.

After a run with the engine warm , use a "flit" gun a hand held insecticide pump from decades ago filled with tap water.

Idle the engine about 1200-1500 RPM and spray tap water in the intake with enough volume that the engine stumbles , but does not stop.

The water steam cleans the carbon out , on a vehicle a piece of newspaper behind the exhaust will show the results.

Doing this before the next oil change is quick and simple.

Thanks, Fred. The higher pitched metallic rattling you can hear late in the vid above has got me wondering if it’s carbon.

 

[Ski in NC]

Sort of missed the update til now..

I hear a little bit of a rattle, is that what concerns you? The motor sounds normal, no carbon type piston slap I was thinking about.

Some rattle in the damper plate/gear is normal on a diesel. Some it is very noticeable, some almost nothing.

But you noticed a change? Do you know what kind of damper plate was put in when the TD gear was installed?

My gut feel is to not get too excited about this. Worst case would be to pull back the gear and inspect damper plate. If it looks good, get the numbers off it and maybe carry a spare.

What kind of sounds do you get when shifting in and out of gear at idle? A worn damper plate often makes noise then. Another vid may be helpful.

 

[angus99]

Thanks, Ski. I’ll post a vid in a little while to see what’s happening when shifting.

 

[DavidM]

Years ago, and maybe Ski will remember this as he came out and took a look at it then, I had twin Yanmar 3GM30Fs in a sailing catamaran. The port engine ran fine, but the starboard engine was a little hard to start and sounded very much like yours.

The sound didn't change much at higher rpms and didn't change when you shifted into gear, so Ski didn't believe it was the damper. He said to keep an eye on it, but if I didn't have a twin to compare it to, I would never have questioned it. He also suggested checking the injector timing and I did and it seemed to be within spec.

Some hundreds of hours later I replaced the injectors and the hard starting and clatter went away.

David

 

[angus99]

Here’s the latest. Not as noticeable at idle as previously. If anything, it seems quieter when in gear.

The Twin Disc was installed with about 1,700 hours on the engine. No mention in the records about damper plate going in . . . so there’s either 3,400 hours on the plate if it wasn’t swapped out when the TD was installed or 1,700 hours if it was.

https://youtu.be/4jnyWzuR5k8

 

[angus99]

Years ago, and maybe Ski will remember this as he came out and took a look at it then, I had twin Yanmar 3GM30Fs in a sailing catamaran. The port engine ran fine, but the starboard engine was a little hard to start and sounded very much like yours.

The sound didn't change much at higher rpms and didn't change when you shifted into gear, so Ski didn't believe it was the damper. He said to keep an eye on it, but if I didn't have a twin to compare it to, I would never have questioned it. He also suggested checking the injector timing and I did and it seemed to be within spec.

Some hundreds of hours later I replaced the injectors and the hard starting and clatter went away.

David

Thanks, Dave. The engine seems to fire right up. The injectors on both engines were serviced in 2014 and have probably under 100 hours on them since. Not to say that they could not be the problem (if there is a problem) .

 

[psneeld]

I was in the same situation of not knowing the age of the dampener plate...either 2500 hrs or way more.

First symptom was enough clatter to scare me into immediate shutdown and activate a smoke alarm.

A few subsequent rattles were temporary and mild... So I would have a hard time saying exactly what symptoms are normal and we only thought it was a plate from eliminating other issues.

It took another 100hrs till the next symptom which was 2 completely destroyed springs and a jammed flywheel.

 

[High Wire]

It took another 100hrs till the next symptom which was 2 completely destroyed springs and a jammed flywheel.

That must have sounded horrendous.

 

[Ski in NC]

Sounds kinda normal to me. But those damper plates can let go on short order. Hard to give advice here.

Has sound changed recently?

 

[angus99]

Sounds kinda normal to me. But those damper plates can let go on short order. Hard to give advice here.

Has sound changed recently?

Yeah, I noticed it for the first time the other day. And today, it sounds normal. Anyway, it’s got me spooked. A guy’s going to slide the tranny back tomorrow and start it up to see if the noise is repeated or if it’s gear noise. I’m inclined to have both plates replaced while he’s (we’re) working down there.

 

[angus99]

I was in the same situation of not knowing the age of the dampener plate...either 2500 hrs or way more.

First symptom was enough clatter to scare me into immediate shutdown and activate a smoke alarm.

A few subsequent rattles were temporary and mild... So I would have a hard time saying exactly what symptoms are normal and we only thought it was a plate from eliminating other issues.

It took another 100hrs till the next symptom which was 2 completely destroyed springs and a jammed flywheel.

It never ceases to amaze me how components I never knew existed can torpedo months of preparations. (Notice I didn't say “planning.”)

 

[FF]

Damper plates come in different quality levels.


I would check with TD and go by their standard, but ask if a HD unit is available.

 

[angus99]

Update

The Twin Disc was pulled and . . . . nothing. The damper plate is solid—no springs—no visible signs of wear, no cracks on the drive-saver and the engine sounds totally normal with the damper plate on and off. The yard is going to call their transmission shop to see if there’s any concern about the Twin Disc, but since I haven’t heard the noise since those first few times, I’m inclined to button it up and go.

 

[Ski in NC]

Glad you got it checked so quickly. I would not be inclined to dig into the gear.

My vote is to get on down the road.

The things that bite you are almost never the things you worry about.

 

[angus99]

The things that bite you are almost never the things you worry about.

Think I’ll have that put on my tombstone.

I did find a Twin Disc manual with a reference to “gear rattle from torsional vibrations.” The solution: “Raise the low idle setting.” Whenever I raised the rpms from dead low, the noise seemed to go away.

 

[Comodave]

I hate it when you have to read the directions...

 

[angus99]

I hate it when you have to read the directions...

But the instructions wouldn’t have let me rule out the damper plate.

 

[Comodave]

Glad you figured it out.

 

[kchace]

Better to have checked it than worried for your entire trip.

 

[bayview]

Does it have a harmonic balancer? They make clacking sounds not rattles.

 

[Seabag]

I'm curious about the reference to #6 piston slap. We have been looking at a Defever with 135's and the starboard engine has a very definite knock in that location. Current owner says he's had it checked and it's nothing to worry about. Me, I'm a little more skeptical, particularly when buying a used boat. What's the prudent thing to do here - besides a good mechanical survey? Questions to ask? Issues to look for?

Pardon me if I hijacked this thread...

 

[angus99]

Better to have checked it than worried for your entire trip.

Apparently, we’re not done yet, folks. When we started up with the tranny bolted to the engine—but not to the shaft—we heard the clacking in both forward and reverse. No noise in neutral. This is the exact opposite of what I was hearing the other day when the noise was audible in neutral, but not in gear.

WTF?

https://youtu.be/_08qTA173IA

The engine’s not shaking; it’s me trying to hold the camera steady.

 

[Comodave]

I'm curious about the reference to #6 piston slap. We have been looking at a Defever with 135's and the starboard engine has a very definite knock in that location. Current owner says he's had it checked and it's nothing to worry about. Me, I'm a little more skeptical, particularly when buying a used boat. What's the prudent thing to do here - besides a good mechanical survey? Questions to ask? Issues to look for?

Pardon me if I hijacked this thread...

Call Brian at American Diesel.804-435-3107

 

[Ski in NC]

Apparently, we’re not done yet, folks. When we started up with the tranny bolted to the engine—but not to the shaft—we heard the clacking in both forward and reverse. No noise in neutral. This is the exact opposite of what I was hearing the other day when the noise was audible in neutral, but not in gear.

WTF?

https://youtu.be/_08qTA173IA

The engine’s not shaking; it’s me trying to hold the camera steady.

Probably normal. Gear rattle will be worse when in gear with shaft disconnected. See what it does when all is connected.

 

[angus99]

Probably normal. Gear rattle will be worse when in gear with shaft disconnected. See what it does when all is connected.

Sent the video to a tranny shop this yard swears by. Really hope you’re right, Ski.

 

[angus99]

Probably normal. Gear rattle will be worse when in gear with shaft disconnected. See what it does when all is connected.

Sent the video to a tranny shop this yard swears by. Really hope you’re right, Ski.

 

[kchace]

I'm curious about the reference to #6 piston slap. We have been looking at a Defever with 135's and the starboard engine has a very definite knock in that location. Current owner says he's had it checked and it's nothing to worry about. Me, I'm a little more skeptical, particularly when buying a used boat. What's the prudent thing to do here - besides a good mechanical survey? Questions to ask? Issues to look for?

Pardon me if I hijacked this thread...

There is a condition that sometimes occurs on FL 120's that causes the #6 piston to become scored and fail. This problem dos not seem to exist in the 135's but that's not to say that any given 135 couldn't have a piston problem.

 

[BruceK]

There is a condition that sometimes occurs on FL 120's that causes the #6 piston to become scored and fail. This problem dos not seem to exist in the 135's but that's not to say that any given 135 couldn't have a piston problem.

I sent Seabag a PM so as not to mess with this thread,but,I suspect the no.6 cylinder issue has its origins in compromised cooling due to the silting and blocking of adjacent coolant passages that seems to occur.

 

[angus99]

Final (?) Thoughts

Just to summarize:

Yesterday, with the transmission off, we heard no noise of any kind. It is definitely not the damper plate, which has no springs and looks like new.

With the transmission back on, but not connected to the shaft, we only heard a clacking sound in gear—not in neutral.

Today, with the shaft connected, we only heard the clacking sound in neutral—not in gear. (increasing the rpms did not make the sound in neutral go away.)

Here is the sound in gear: https://youtu.be/Un6Hf7-0sZs

Here is the sound in neutral: https://youtu.be/nrkjpzBLpTQ. (The mic makes it sound louder than we can hear it in person.)

We need to make a go/no go decision and I’d appreciate any informed opinions.

Thanks.

 

[Ski in NC]

Gear rattle. You ought to hear my Cummins 450 at 550rpm. Lots of gear noise in N.

If something was wrong with that gear you would hear it when in gear with prop load. If it quiets down with added revs, that is good. If it gets louder with added revs, then time to worry.

My vote is to GO.