PErkins 4.108 Replacement

[exbury2]

Hi there!
Does anyone have experience in changing a 4108 to a Yanmar or Beta engine or other?
Very tight compartment.Restriction of prop size to 18' Would like as few changes to the engine beds as possible.
For the moment:4108 with a hurth 150 2.6 to 1 reduction 18 X 14 " blades prop Maximum revs possible 3000rpm full bore.
Any ideas?
Thanks in advance.
Exbury2

[AnchorageGuy]

We replaced our 4-108 with a Yanmar 56 HP 4JH and it all but dropped right in. We only had to make a minor modification for the forward engine mounts. We actually used the same transmission as the Perkins, with an adapter. Chuck

[Kalinka1]

I would go with the Beta. parts available all over at reasonable prices. Contact Stanley at Beta marine He can and will advise on the installation.

[GordMay]

Greetings and welcome aboard the CF, Exbury2.

Good luck!

[beetle]

Originally Posted by exbury2

Hi there!
Does anyone have experience in changing a 4108 to a Yanmar or Beta engine or other?
Very tight compartment.Restriction of prop size to 18' Would like as few changes to the engine beds as possible.
For the moment:4108 with a hurth 150 2.6 to 1 reduction 18 X 14 " blades prop Maximum revs possible 3000rpm full bore.
Any ideas?
Thanks in advance.
Exbury2

Yes - Perkins 4-108 replaced with Yanmar 4Jh5E, retaining the existing Hurth 150V transmission and prop shaft, and changed the propeller from a Martec 2 blade folding to an 18" diameter MaxProp 3 blade feathering. I repowered starting in November of last year, and over the weekend was finally able to haulout (with clear weather here in San Francisco) to repaint the bottom and put on the new MaxProp.

The Yanmar 4JH5E is slightly smaller in all dimensions than the Perkins 4-108, produces slightly more horsepower (53 vs 50) at much lower revolutions (3000 vs 4000). The increase in piston displacement is huge: from 108 cubic inches to 134 cubic inches.

I can provide all the details of exactly what I did, if you're interested.

Work involved: replacing entire exhaust system, adding second water lift muffler, replacing (and raising) engine beds, replacing engine gauges and then replacing the tachometer mechanism, moving fuel filters, replacing alternator, moving the raw water intake thru-hull, and a host of other small issues. Total cost was $22,350 (that's all for parts, less $90 for 1 hour consultation on the exhaust system - everything else I did myself). Upshot is the only original part of the Perkins remaining on board is the transmission and prop shaft.

Motor works a treat, is quieter, lighter, more powerful, and the three blade MaxProp is quieter than the two blade Martec plus developing more power at the cost of some additional drag under sail.

- rob/beetle

[doug86]

Another vote for Yanmar 4JH.