Yanmar engine mount

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marcuc

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Has anyone found an effective replacement for yanmar rubber mounts. I have new 100 front 75 rear as per spec on a 3ym30 and they seem very soft. Was considering using isotherm solid plastic
 
Why are harder mounts better? I couldn't manage to get the clearance recommended in the installation guidelines for my ym30 but it hasnt been a problem but I was amazed to read that the engine mounts should be changed every 2 years. I fitted drip protectors on mine which seem to have helped to prolong the life.
 
Hi Marcuc.
This is my opinion.
The Yanmar engine mounts were designed almost 50 years ago.
They are still manufactured to the original specifications.
The materials: synthetic rubber, galvanized brackets, bolts, are still made to those old specs.
In the mean time technology has moved on.
Newer, stiffer, more long lasting stainless steel mounts are available.
Use the newer mounts.
This is a case where the stamp, "Yanmar" does not equal good or better.

gary
 
The Ellebogen ones aren't stainless just claims stainless like protection. Not sure why harder is thought better. It's the frequency response that counts.
 
Mine are Polyflex from Australia. Fitted from new. Unfortunately they're a barsteward to get in the UK now as Southern Cross Marine who imported them seem to have closed (I'm currently trying to get another set for a different engine). There's another company listed as importers but they've ignored two emails from me now so they can do one.

Can't recommend the Polyflex mounts enough. Fully rebuildable and designed for Yanmar to start with, they don't rot, the engine doesn't wobble about all over the place, they don't need replacing every 5 years, uses the same bolt holes too.
Yanmar couldn't make enough profit on them so they didn't use them as OE and stuck with their original ones which are probably a lovely income stream for them. £25 each to make, sell for £600+ per set.

With Polyflex you need the correct shore hardness for your engine and all four need to be the same.
 
When I noticed severe cracking of the rubber on the engine mountings of my Daihatsu Skywing (Taiwan version of the Charade) I looked into casting replacements, which did appear to be possible, but I couldn't find the stuff locally or a source that would ship it. There were some Internyet reports of people carving mountings and bushings from ice hockey pucks, but none of the local Canadians had any they were willing to part with. 3M Window Weld is apparently a slightly less professional substitute for eurethane casting resin but I couldn't find that either.

As a forlorn hope I ran superglue into the cracks after degreasing with solvent (either ethanol or acetone, dont remember) and put them under compression with multiple cable ties (The rubber looked like it had failed in tension under engine torque, probably after weakening by leaked or spilled engine oil). I expected the cable ties would bust and the glue fail.

Over 10 years later they were all still there when the cops got the car. I doubt the glue was doing much and suspect that the cable ties would have worked alone, but cant be sure

So if this happens to my Yanmar mounts I'll probably try that, if the geometry allows it.

I THINK putting the rubber under compression effectively increases the stiffness, at least when engine movement loads the mounts in tension.
 
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Fitted R&D to replace the Yanmar ones, but they are much shorter, so put pads under them to reduce the length of the threaded bar to the engine mounting brackets. Pads were 30x60 mm SS tube.
This was on a 1GM10, but did the same when swopping a 2GM20 for a Beta.
 
I changed my yanmar engine mounts when I first purchased my boat. Changed from the standard yanmar ones for R&D Super Mounts in 2009 after an engine bay refurbishment. They were then approx £125 for a set of 4. Yanmar ones were well over £300.
Engine is a yanmar 2gm20, and they did need a packer underneath them but they have lasted well. I have only had 2 x sets in the last 16 years and the last ones fitted are still performing well.
 
ducked said:
When I noticed severe cracking of the rubber on the engine mountings of my Daihatsu Skywing (Taiwan version of the Charade) I looked into casting replacements, which did appear to be possible, but I couldn't find the stuff locally or a source that would ship it. There were some Internyet reports of people carving mountings and bushings from ice hockey pucks, but none of the local Canadians had any they were willing to part with. 3M Window Weld is apparently a slightly less professional substitute for eurethane casting resin but I couldn't find that either.

As a forlorn hope I ran superglue into the cracks after degreasing with solvent (either ethanol or acetone, dont remember) and put them under compression with multiple cable ties (The rubber looked like it had failed in tension under engine torque, probably after weakening with engine oil). I expected the cable ties would bust and the glue fail.

Over 10 years later they were all still there when the cops got the car. I doubt the glue was doing much and suspect that the cable ties would have worked alone, but cant be sure

So if this happens to my Yanmar mounts I'll probably try that, if the geometry allows it.

I THINK putting the rubber under compression effectively increases the stiffness, at least when engine movement loads the mounts in tension.
Click to expand...
Zip ties are amazing
 
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