July 15, 2016
A while back we installed new engine mounts. Since replacement Yanmar mounts were so expensive, we went with R&D mounts sold by PYI. I’m thinking this was a mistake, but not totally. Here, watch this…
The Pros:
Very smooth at cruising RPM. Less $$$.
The Cons:
Very rough at idle! Maybe so rough that I’ll have to go back to Yanmar mounts soon.
A difficult installation with modifications to the engine brackets required. This is not a straight bolt in proposition, even with the mount R&D makes with the shim that is supposed to be a bolt-in replacement for the Yanmar mounts.
I emailed back and forth with PYI about this issue. Here’s how it was resolved (as far as they’re concerned)…
R&D asked if you have the tick over too slow? They also made a comment that the 3 cylinder engine is inherently out of balance. I know the Yanmar mounts are softer and at low rpms may absorb the rattle better. R&D control the engine much better when thrust is applied, but may be too stiff for the rattle at low rpms. We have used these 800-037 before on 3 cylinder Yanmars would good success, that is why R&D is asking about the tick over.
By “tick over,” I’ve come to believe they mean the idle speed. It’s exactly at Yanmar’s specification as verified by a laser tachometer. I don’t get it… “we’ve used them before on 3 cylinder Yanmars with good success” and “may be too stiff for the rattle at low RPMs.
This is by no means a complaint about PYI. They are a very impressive company with incredible customer service. They have done amazing things for us in servicing our MaxProp. They just sell the R&D mounts and I’m not sure R&D understands the purpose of customer service.
At any rate, I would say avoid these if you have a Yanmar 3YM30 (or maybe any three cylinder diesel). Overall, they get a boo from us. -Rich
Update: February 6, 2017
I received this email…
This is Bruce from s/v Migration. I was looking for Yanmar engine mount information and ended up on your site. Wanted to let you know that we had the EXACT same experience with the R&D mounts. Installed them and they ran great at higher RPM but were horrible at idle. You sure realize quickly how much time you spend at idle with those mounts! We finally pulled them out and put our old Yanmar mounts back in. I was online today to find some new Yanmar mounts which is why I was googling.
We also had the same issue with PYI (who usually provide fantastic customer support). They told us to check the idle. Also said to switch the two different types of mounts (we have a 4JH2-TE) from front to back instead of side to side. But we weren’t going to do that because that’s not how Yanmar mounts work.
Further update:
On Legacy, we’ve raised our engine idle to just over 1000 RPM and it helps. I don’t think shifting at higher RPMs is very good for the gearbox though.
After just a little over a year of use, the mounts have gotten soft enough that there is more lateral engine movement and this creates a pretty bad engine alignment issue when motorsailing.
I will definitely put Yanmar mounts back on the engine. -Rich
Update: March 11, 2018
Well, we did it… we bought new Yanmar mounts and installed them. We threw the R&D mounts in the trash. We haven’t been out for a ride yet, but in the berth, the engine is so much smoother and quieter!
Update: September 9, 2018
We have 1,500 miles on the new Yanmar mounts now in lots conditions, including motor-sailing in rough conditions. They’re great. The hold the engine in place even when heeled over and do an excellent job of dampening the vibrations. It feels like a new engine. I wish I’d never heard of R&D mounts!
