Silent Rider Mufflers

[ibelieve]

First, are Silent Riders only a Malibu thing? I thought they were used in several types of boats but I haven't been able to find much about them on the internet.

I installed a pair of silencers from Peter and they do take some of the roar out of it but I can't say they make it quiet. I would like for no one to know I am there early in the morning ... may be asking a bit much.

Sources? ... my local dealer and Peter? Is shipping cost an issue?

Thanks,

Steve

[Rip6@36]

My Silent Riders just arrived yesterday. I ordered them for my 03 Response LXi. It was quite an effort to find them. My dealer didn't know anyhing about them. They had installed the tips before but not the mufflers. Anyway, I finally got in touch with one of the technical people at Malibu CA and they gave me the part numbers-then I had to give those part numbers to my dealer and he ordered them from Malibu. I tried to go direct through Marine Muffler with no luck. Here are the part numbers I received directly from Malibu:

3231021 Port Side

3231022 Stbd Side

You may need hoses and I have those numbers if you need them. The mufflers were $179 each.

PS: I have a Monsoon 335

Rip

Edited August 16, 2007 by Rip6@36

[ibelieve]

I'd be interested in knowing your thoughts on them, once installed.

Do your's have the elbow on the end or are they straight? Mine have the elbow. I was hoping they would be a direct replacement for the muffler I already have.

Thanks,

Steve

[Rip6@36]

They have the elbows on the engine side. They shipped them from the dealer yesterday, so hopefully I'll have them tomorrow and can install them this weekend. I'll post how they work out.

Rip...

I'd be interested in knowing your thoughts on them, once installed.

Do your's have the elbow on the end or are they straight? Mine have the elbow. I was hoping they would be a direct replacement for the muffler I already have.

Thanks,

Steve

[GrahamH]

Can you post a picture of them? I am very intersted to know if you think they make a difference. I talked with David Parks of Marine Muffler almost 2 years ago and he said the following:

- silent riders are a muffler system for V drives, they cannot be fitted to a direct drive without installing an oversize motor box because they incorporate a tank.

- what Malibut call silent riders for a direct drive are really Primex Silencers with a hose connecting the pair of mufflers.

- the difference in a direct drive would be about 1 dB compared to the standard Primex mufflers that come with the boats

I decided to spend my money on the Hydro Power turn downs and they did drop the noise 5 to 8 dB which is significant when you are around 100 dB. I took before and after dB reading in various parts of the boat.

Motor box insulation was going to be my next line of action but the Hydro Power turn downs took enough edge off the noise that I the insulation slipped off my to do list.

For me, moral of the story is that if you are buying a new boat, make sure the silent riders, motor box insulation, and hydro power turn downs are specified. They don't add up to a lot extra. Retrofitting them is very expensive and time consuming.

My boat is an 05 RLXi with the 383 HH

[LakeOneSkier]

... I decided to spend my money on the Hydro Power turn downs and they did drop the noise 5 to 8 dB which is significant when you are around 100 dB. ...

Where can I find info on the Hydro Power turn downs?

[1FootDan]

PM Smoothwaterman, he can ship you a pair. That are also know as STE. I have both Primex and STE and the make a huge difference from the stock silencers. The end result is so good, that the first time I took a fall long line and my wife turned the boat around slowly (to prevent rollers) I tought to myself, "Sh|t, why did the engine shut down?", then I saw the boat moving towards me without hearing anything. So much, that my neighbor who had as a Sportster couldn't beleive the difference, he went out and ordered both Primex and STE to have the same result.

[ibelieve]

I have Primex mufflers (marinemuffler.com) but don't think they are the Silent Riders. If they are, I'd be surprised.

Options for silencers are, as mentioned, HydroPower from Smooth Water Sports (Peter) or some of the less tried silencers.

http://www.hpisilencers.com/

http://shopping.rexmar.com/

/Steve

[1FootDan]

Has anyone tried these? They almost sound erotic...

Shotgun Silencers

Shotgun Exhaust Silencers by Drew Marine 4" - Pair

• Shotguns produce a nice throaty sound level

• They may or may not pass local noise regulations

• Manufacturer claims no top end power loss

• Computer designed to automatically control proper back pressure

• Can actually improve bottom end and mid range power

• For use on engines 250-670", blown or naturally aspirated

• They attach with a small bolt and slide over tip or collector

• Drilling of exhaust pipe is required to install

• Spring loaded recoil cylinders regulate the pressure and opening

• Rex Marine's tests indicate about a 5-6 dBA reduction

[ibelieve]

Rip,

Any update on your silent riders?

/Steve

[Rip6@36]

I installed them tonight. I'll post pictures and my install experience this weekend when I have more time. They quieted it a bit, but not as much as I had hoped.

[Rip6@36]

Okay, sorry it took me so long. I skied and worked tournaments all day Sunday and Monday.

First, I'm changing my review of the mufflers. They made a very significant difference. I had not skied behind the boat when I wrote the last post. Behind the boat you can really tell the difference. You have to turn your head even to hear the boat-skiing all you hear is the wind in your ears. A couple of neighbors said they couldn't hear the boat with the doors and windows closed-before they could. Inside the boat-not much difference. I think insulating the motorbox will help with that. Worth it-yes in my case.

So for the do it yourself installer.

-Make sure you pick up riser gaskets. I didn't and the install was much harder because I didn't remove the whole riser top and exhaust assy. If you remove the 4 bolts holding the riser and losen the exhasut clamp on the back of the muffler, the whole assembly will come out and you can put everything together in the bench and then reinstall in the boat.

-The stock mufflers have 60 degree turn-up tubes glassed on the mufflers toward the engine. My silent riders were straight-no 60 degree tubes. I ordered the 60 degree tubes from Malibu seperate but they sent me 90 degree tubes that would not work, so I cut the old ones off the stock mufflers and used those.

-You will not be able to remove and install the old or new mufflers if the 60 degree tubes are glassed in place. Someone here wrote that they had a set to install that had the tubes glassed in place. Everything is so tight and the rubber hoses are so stiff, there is no bending them to remove or replace them. I had to cut the old mufflers out. Again-PLAN ON REMOVING THE RISERS. Because my system is 4 seperate pieces, I was able to do it without removing the riser-but it was much harder.

It took me 3 hours in all-including trips from the dock to the garage. If the new mufflers have the turn-up tubes glassed in place and you remove the risers it would easily take half the time.

As far as the cross over tube goes, that was easy. Just leave the clamps loose and spin both mufflers so the inlet tubes are pointing slightly up and with the 2" hose cut to the proper length, spin both muffler tubes to the proper position while sliding the hose over the inlets. Then tighten everything up.

I'll attach a couple of pictures.

[ibelieve]

Here's the scoop from Malibu (TN). They claim the silent riders are connected to the riser with a 26" hardwall hose. Apparently the hose can make the bend however, the mufflers may need to be moved back, requiring the hoses at the rear of the muffler to be shortened.

I was also told that it is a 9" piece of 2" hose that connects the two silent riders together. He thought it might be fuel fill hose, but not sure.

I'll post some pics when I get mine done.

Thanks,

Steve

[RTS]

I think insulating the motorbox will help with that. Worth it-yes in my case.

It makes a world of difference...this is my first summer with the motorbox insulated, and it was well worth it.

[Rip6@36]

You are correct. It is fuel hose. I bought both the 2" and the 3 1/2 inch from Malibu. We tried to bend the hose and it was too stiff in my opinion and at $14 a foot, it is crazy expensive. By cutting off the 60 degree tips from the stock mufflers, I only needed two 6" pieces of 3 1/2 in hose. Also by using the turn-up connectors, the muffler is suspended in the air just like the stock muffler. I was concerned that I would pick up vibration if the hose contacted the hull decking or stingers. If you just bend the hose it will contact the motor box cross member and the hull deck.

Rip

Here's the scoop from Malibu (TN). They claim the silent riders are connected to the riser with a 26" hardwall hose. Apparently the hose can make the bend however, the mufflers may need to be moved back, requiring the hoses at the rear of the muffler to be shortened.

I was also told that it is a 9" piece of 2" hose that connects the two silent riders together. He thought it might be fuel fill hose, but not sure.

I'll post some pics when I get mine done.

Thanks,

Steve

[Chris122]

@Rip6@36 this is a long shot but recently broke my silencer and it’s the exact same one you ordered years ago I seen you said you called Malibu CA but I can’t seem to find any of the same ones …

[justgary]

8 hours ago, Chris122 said:

@Rip6@36 this is a long shot but recently broke my silencer and it’s the exact same one you ordered years ago I seen you said you called Malibu CA but I can’t seem to find any of the same ones …

How broken is it?  It may be far cheaper and easier to just repair yours with some fiberglass and resin.

[Bozboat]

1 hour ago, justgary said:

How broken is it?  It may be far cheaper and easier to just repair yours with some fiberglass and resin.

New ones are pricey