Westerbeke 7.6 BTD Vibration/Noise reduction

dtfeld said:
Got the back rail 1/2 out...the front bolt is stuck good...multiple overnight shots of PB Blaster, heated a side of the nut with a small butane torch...cant get it loose. Any other advice before I go all in and cut it out with a dremel tool? Biggest issue is I can get enough travel on the wrench.

View attachment 77441

Also found why it was so hard to remove the drip pan...it was bolted down! Is this the normal install technique?

View attachment 77440
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It looks awfully tight, but is there any to get an impact wrench / rattle gun on there ?
 
I hate to admit this but I am in a similar situation with the front rail. Got the first bolt out easy, the second one is so stuck i sprayed it with PB blaster and left it for this weekend.

I did learn something... Rust Oleum gloss sunrise red is an almost perfect match for 4 bucks at home depot.

Josh
 
the drip tray can be held down with a dab of sealant instead of passing screws through. the reason for the pan is to collect drops. if there are holes, they need to be sealed well.
with the amount of oils, loose paint flakes and the like, please be careful with even the smallest flames. i have had it happen and boy, its scary. if you dont want to remove the generator from the boat and place on a work bench ( which is what i would be heading towards), you can go to the pawnshop. get yourself a good deal on a sawzall. buy some new blades. reach in beneath the back ends mounting flange and let the saw do the work. cut the mount bolt away. have a lift or some blocking beneath the generator so that there is a slight upward tension. of course, place blocks under so that the machine cant fall on you. never commit a part of you under a machine. get long saw blades and reach in. been there. hope this is of benefit.
 
I like the Sawzall idea!!! And yes it is very tight, like my wallet right now!

Problem with the front bolt is the nut is on the top and the generator pancake interferes with the removal from the top...in other words I wouldn’t be able to get the bolt out.

Needs to be cut from the top I think...let me go look and contemplate. It really wouldn’t be to tough to get the whole genny out from here, but would become a multi man job.
 
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Obviously these were meant to be installed with access from the bottom. But I’m not ready to pull it just yet.

New rail from bottom.

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And finally. I cut it out with a dremel tool. Calling it a day, go get new bolts and recover from the contortions.

Tomorrow, I’m going to drain the anti freeze and clean the area. Reassembly later in the week.

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invest in an inversion table. hang upside down like grandpa on munsters. it helps...
 
Making progress and cleaning up a messy bilge. Might get the rails in yet today.

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And both rails back in. Just needed some 2x4s to block the genny up while i installed the new rails/isolators.

Now new exhaust hose and ill give this a test.

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Old rails out...the back outside isolator looks like it failed long ago, and in the worst shape

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dtfeld said:
And both rails back in. Just needed some 2x4s to block the genny up while i installed the new rails/isolators.

Now new exhaust hose and ill give this a test.
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I suspect mine is going to need this same treatment. How did you jack up the genny to be able to block it with the 2x4s? I think I only have about 6" headroom over mine, how high did you have to raise it?
 
GnrlPatton said:
I suspect mine is going to need this same treatment. How did you jack up the genny to be able to block it with the 2x4s? I think I only have about 6" headroom over mine, how high did you have to raise it?
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I used a 2x4 about 24” long and just muscled a couple 2x4’s on edge underneath. It didn’t take much, I accomplished it by myself. I also had to remove the exhaust tube and the rear vacuum pump plus all the hoses going to it to allow me to move it around to access the rear of the unit. The biggest bitch was getting the rusted bolts loose.

Once that was done it was a couple hour job. Also got new exhaust hose installed today I also sprayed degreaser and scrubbed as much rust and oil from under it and installed a new drip pan.

The upshot is this was a MAJOR improvement in the sound level!!
 
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Just realized in looking at my pictures, I assembled one one of the mounts incorrectly.
 
Sorry to jump in on the thread. My isolators are gone after 20 years also but not as bad as the pictures in this thread. My 7.6 in my 2000 Sundancer rattles on start and shutdown. I agree there is not much room to lift the Genny but the suggestions with the 2x4 will help.
I am presently on a mooring in Fort Myers Beach and was going to get a local shop to change the isolators and save my back but this will take some more planning on my part. The quotes I am getting locally is the hourly labour cost without any really plan or experience doing this job. That may not work budget wise as this is definitely more than a couple hour job. Thanks for the great tips and I am not looking forward to pulling the aft vaccum generator out. Another recommendation is all new hardware.
 
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Yesterday I ordered the isolators but the hardware was on backorder from the distributor. After reading this I ordered the rail assembly for each side that comes with all the hardware and isolator excluding the center capscrew and nut. That is available next week. I have talked to two marinas in Ft Myers who don't want to take this on so I will do it myself. The tips offered in this article will help me big time.
 
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3 big take aways.

1. Get the hatch support, exhaust tube and aft vacuumed generator out of the way.

2. Don’t spend much time trying to get the nuts on the isolator bolts loose. Get a dremel tool and cut the nuts loose, and replace the hardware.

3. Buy the rail assemblies and just slide them into place. Don’t fool around with the isolators.

I think this is a 10-12 hour job to get everything done.
 
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dtfeld said:
3 big take aways.

1. Get the hatch support, exhaust tube and aft vacuumed generator out of the way.

2. Don’t spend much time trying to get the nuts on the isolator bolts loose. Get a dremel tool and cut the nuts loose, and replace the hardware.

3. Buy the rail assemblies and just slide them into place. Don’t fool around with the isolators.

I think this is a 10-12 hour job to get everything done.
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@dtfeld , I just stumbled across this thread. I need more jobs like a hole in my head but I can see tackling this in the spring. I'm thinking my fancy harbor freight hydraulic tool could assist in lifting the genny as necessary

Where did you order the rails and isolators from? I'm thinking mine are also toast, the boat vibrates pretty good when it's running. You said it made quite a difference, right?

Our genny only has 92 hours on it. I plan on running the shit out of it this year and the quieter the better
 
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@Strecker25

Parts are direct from Westerbeke. Part numbers 38148 and 38149. Rail left and right. About $300 for the assemblies. Made a big difference in the vibration You can feel and hear it through the boat/hull.

I think there are 3 things that will improve the noise and vibration level on this model. 1. Upgrade the muffler to a dual stage (cuts the engine noise. 2. Replace the rails (cut down on vibration through the hull) 3. Add a soft sided sound shield (the remaining noise primarily comes out out he engine air inlets, but that’s right where the cockpit seating is).

I did the first 2, and the soft sided sound shield in high on my wish list.
 
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