Motor Mounts

[Ken Juul]

Planning on replacing mine this week.  The K75's came with no instructions.  I'm guessing the wavy washer goes between the engine flange and the top nut, acting as a compressive lock washer.  If that is correct, any need to add a flat washer between the flange and the lower jam nut?

I am planning on using an automotive scissors jack under the transmission to hold the engine at the correct height, then replacing the rear mounts one at a time.  Then moving the jack to the front of the engine for the front mounts.  I'm hoping the jack will hold the engine in the correct alignment so that the exhaust, shaft and other bits and pieces won't need to be disconnected.  Do able?  I think I will need to remove the adjusting bolts from the rear mounts to get them out.  Possible or are they usually rusted together?

[lucky]

Ken I'd like to know how this works out .I thought the shaft had to be disconnected. I'm going to replace my mounts soon.Are using k75 front and rear? thanks
Lucky
c34 hull 13
Al Landry

[Craig Illman]

Ken - I cut the stubs on the old mounts with a sawzall as recommended in some historical thread on my C34. This is next winter's project on my C30.

Craig

[Paulus]

Ken, I did my motor mounts about 10 years ago.  Had to disconnect the shaft and also the exhaust hose from the engine to the muffler.  Replaced the old hose with new hump hose at the same time.
Also, used the jack.
Paul

[Ed Shankle]

Same as Paulus, I did mine about 10 yrs ago too. Did it in place, disconnected the shaft though. Thing is, you might need an alignment now anyway, so why not assume that and benefit from it, even if it is minor adjustment?

Ed

[Ron Hill]

Ken : If you want to raise the engine you'll have to disconnect the drive shaft and the exhaust riser at the muffler.

On your question of a flat washer - it may be needed so the wavy washer has a complete surface (hole in the engine mount bracket) to compress itself against.

I did it both ways  1. lift the engine and 2. cutting the old mount with a reciprocating saw. The saw was by far the easiest and fastest.  If you make your self a height gage before you saw and install the new mount raising it to the same height, you might not have to realign the engine!! 

A thought

[Roland Gendreau]

I replaced my mounts, one at a time, with K75's. I did not jack the engine up as 3 mounts will keep the engine pretty much in place.  I cut the shafts of the old ones with a sawzall type tool.   I removed the threaded shafts of the K75's in a vice at home, slid each mount under the motor bracket, secured it with lag bolts and then threaded the shafts and nuts back on. I did a re-alignment of the engine afterwards, thinking that there was no way I was going to put the new mounts in so perfectly that no re-alignment would be necessary. 

[Ken Juul]

Well 3 of 4 are complete.  A riciprocating saw is a must for this job. If you don't own one, borrow or rent one.   Especially the rear mounts, next to no clearance if the engine stays in place.  Pretty much copied Roland's method, although I did put a scissors jack under the engine for extra support.  Got to the final one under the alternator, put the socket on to break the top bolt and the engine mount flange seperated into two pieces.  I knew this was a problem on the M35 engines, I don't recall it being an issue on the M25xp, but there is always a first time.  Will get it welded, will probably add a sister over the break area, will see what the welder says.  Back to the boat next week to finish the job and begin recommissioning.  Glad this is a once in 20 years job, the rear port one is a PITA.  I used the height guage that Ron mentioned.

[Craig Illman]

Looks like it was a timely endeavor. Another handy tool I remember buying for this project was an eighteen inch long 3/8" extension to tighten the lags bolts from above.

Craig

[Indian Falls]

I went through all this already too.  http://c34.org/bbs/index.php/topic,6386.0.html   
I did not disconnect the prop shaft or the exhaust. I did not move the engine.  I removed the old mounts with a saw and installed the new ones one at a time.  I would not go with vetus 50's and 75's go with all the same, the hardest ones, not the softer ones.  Keep shaft alignment in the back of your mind.  You may need lateral adjustment, without enlarging the mount holes you could limit side adjustment you may need.
Make sure you comb the whole forum, there is lots of info concerning motor mounts.

[Ron Hill]

Ken : Thought you knew that there was a service bulletin put out on the gusset fix for the M35 engine mount brackets  !!

I believe that it is listed in our lengthy Critical Updates .   

[Rick Allen]

Broken forward/starboard engine mount flange?
Been there, done that.....

[Roland Gendreau]

I also had 2 motor brackets fail the same way on my M25XP. I contacted Joy Joyce at Westerbeke and they replaced the brackets with ones that have a long gusset.   I had one of the old ones welded, in order to have a spare.