New engine mounts on a Perkins 4.108

[danielefua]

I have to renew the mounts of my old Perkins 4.108 and after extended searches and discussions I have finally almost decided about the R&D Marine Super Mounts Shear Loaded model 800-11. In particular they are very similar to the ones fitted now and will require no adjustment.
I have only one remaining question: looking at the tech drawings, it appears that the base of the mountings (the lower flange that is fixed to the boat beam) is made of two wings connected to the upper part with rather little bulk material; in this aspect they are quite different from the present mountings. I wonder if this is just a baseless impression or it is an important issue of these mountings.
I would appreciate to hear the experience of other forumites.

Daniel

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[Deleted member 36384]

I doubt that it matters much as the thin flange will not be stressed significantly because of the rubber blocks in the engine mount (I assume these mounts have isolating rubber and are not solid). Just make sure that the engine bearers where the mount is attached is flat and flush i.e. when bolted down there is no stress due to misalignment across the flange. The mounts for fore and aft are normally different, with the flywheel end having a harder rubber, IIRC. This was the case with my Perkins 4236, which I grant may not be relevant.

The guy below was really good 5 years ago when I replaced my mounts. Initially they were listed as obsolete parts but he searched around and found that they had been re-listed with an 'alternative' part number. He advised me about the different mounts for fore and aft (dimensionally identical).

Perkins, Sabre, Volkswagen, MaK and CAT Parts

John Withey
Finning Power Systems
19 Witney road
Poole
Dorset
BH17 0GL

Tel: 01202 330715
Fax: 01202 330771
E-mail: jwithey@finning.co.uk

 

[AndrewB]

I had constant problems with mounts of the 800-36 type. Although technically rated strong enough to take the load of a Perkins 4-108, actually the front two mounts were taking much more than half the total weight, and failing very quickly. Eventually I too fitted the 800-11 type which are rated for a higher load and resolved the problem. They are also better protected against oil leaks to which the 4-108 is very prone. These leaks perish the rubber of the mounts.

I do not recall any major problem with the base fitting when converting, they are both 4" spacings, but the holes had to be enlarged very slightly to take the old bolts.

 

[danielefua]

Thank you both.
I wrote an e-mail to John Whitey asking if he can provide the proper mounts. In any case I appreciate the confirmation that the 800-11 do not have problems; they remain an additional possibility.
Just to be sure, AndrewB: can I interpret that "I do not recall any major problem" actually means "I do not recall any problem whatsover"?
It makes quite a difference!

Daniel