R21-EC Engine Mounts on VP D1-30

[Newf]

A couple of questions that hopefully someone can help with and share opinions. Thanks in advance.

On my 2014 R21-EC I have the engine mount style as shown below in the pic with the single mount. I am on my second set due to cracking in the rubber. I replaced the first set after about 1450 hrs. The second set now has around 600hrs and is also showing signs of cracking. (Note: Majority of hour are trolling hours so I know this is when the engine vibrates the most and will reduce the life of the mounts) There are photos in my album showing the typical cracking found on the first set.

Question 1--Are all of the D1-30's in the R21-EC equipped with this style of engine mount?
Question 2--Has anyone notice cracking in their mounts? If yes, has anyone replaced the mounts and at how many hours?
Question 3--Has anyone used or seen the type of mounts shown in the second photo showing the D1-30 engine? Were they considered to be better or worse with respect to engine vibration, hull vibration, longevity etc?
Question 4--Are there techinical reasons why I should stick with the style of mount currently on the engine?
Question 5--I have been doing lots of reading on coupling alignment after replacing the mounts and one document talked about ensuring that all four mounts are meant to carrying equal weight. How is this accomplished? Are they referring to equal height adjust on the rear two mounts as a set and the front two as a set because it would be unlikely that the front and back would be of the same height?

 

[bob daily]

Newf, I have the yanmar motor mounts and at about 800 hrs they are showing some cracking, not enough to replace yet, but enough to start looking for replacements in case of a failure. The yanmar mounts come in front mounts with 75 Kg load rating, and aft ones with 40 Kg load rating. Looking at them you can't tell the difference. As far as the mounts in the picture with the motor it looks like it would be difficult to inspect and would not know of a problem until a full failure happens. I would think that if the bolt pattern was the same, any good quality mount would work!
Good luck on your repair and keep us posted. Bob

 

[Newf]

Hi Bob,
Thanks for your response. I've been doing more following up on other boating and engine forums and from some of the post it appears that the existing mounts are the latest change by Volvo from a Ventus mount as a result of many complaints of high vibrations. (Just going by what I've read)

I guess it's not just a matter of getting ones that will fit as too soft can increase vibration and too stiff can lead to other issues and also higher vibration through the hull. Don't see any markings on the existing ones to indicate who makes them and nothing to show that the front and back are different.

There are many makes and models out there so I will continue to look for something that may work for me. I just did an alignment check on the shaft coupling and all is well in that respect so the cracking in the rubber that currently exists has not affected the alignment at this point.

My running at idle speed most of the time certainly doesn't help but I'll keep on chugging.

Thanks again for your input.
Newf