Perkins 4.108 - Rebuild or Replace?

[gandalf]

In my quest to restore my beautiful new (old) Vancouver 42 the time has come to make a decision on repowering. The oil leaks, smoky exhaust and coolant loss are all signs that some serious surgery is required. One option is to buy a new engine, which would require changes to engine mounts, an adaptor plate for the gearbox, realignment etc. An alternative is to take out the old Perkins and have it rebuilt, effectively having a new motor without the installation hassles. However, it would still be an outdated motor and everyone I've spoken to says that Perkins are renowned for leaking oil, something I hate seeing in my bilge.

Does anyone have any similar experiences with Perkins engines, either replacing them or rebuilding them?

Cheers,

Frank

[johnar]

Yes they are known for the oil leak but did the people tell you they last forever.

I sit here right now with a Perkins 4-108 that I blew the head gasket, yes I had a oil leak very small, but for the time I have had this boat it never let me down.

I would pull it and have it rebuilt by a well known Perkins man, it will out live you.

Dutch

[forsailbyowner]

I second that. Mines original from 76 and still running strong. I lose very little oil. If I keep the rpms down I get in the hundreds of hours before adding. Rebuild kits are only around $600 with sleeves and pistons.with the replaceable valve seats and guide they're very much made to rebuild compared to the throwaways built today. Rebuilt engines can be had for $4k -5k.

[Boracay]

I would expect a new engine to be way better than your old Perkins.

However the repowering doesn't stop with the engine. Transmission, fuel lines, exhaust, propeller, maybe even a new propeller shaft (and more) are all going to add to the cost, time taken and stress.

If a few oil leaks are your biggest concern then I'd go with the rebuild and a drip tray.

If one of the marinised Kubota, Nissan or Mitsubishi (or similar) based diesels are a drop in replacement they would be worth considering, but don't forget to factor a new propeller into your calculations.

[anjou]

And you can get Perky parts almost everywhere.

[Sharkman]

Stick with the 4.108. Apart from the leaks (which are seldom more than an eyesore) they are slow revving, long-living, solid old lumps. As others have said they can be re-built at low cost - I ran one in a working charter boat for 17 years and re-built it twice during that time for a fraction of the cost of a replacement.

And one thing that endears them to many is that they are all mechanical, i.e. no ECU to give trouble. A new engine might be smaller, lighter and quieter, but I bet it won't last like the 4.108.

[donradcliffe]

I replaced my 4108 with a Beta, and it was a pretty good fit, with no exhaust, water, or fuel modifications required. I did build up the engine stringers by 1.75", but you can get custom mounts from
Beta so you don't have to do that. My bilge is now oil free.

[jkleins]

I just repowered from a 4.108 (it is for sale for parts if you want it. ) on it's second rebuild and it was pretty expensive to modify everything for a Yanmar 4JH4 due to having to lower the engine to line up the shaft. I have to admit though that the new engine is significantly quieter then the other. It used to sound like a factory in the pilothouse and now more like a loud car

Jim

[SvenG]

I'd stick with the rugged serviceable Perkins rather than going for an expensive refit with a delicate modern replacement.


-Sven

[sailfish2008]

i have a 4108 in my boat and i have absolute faith in it. if and when the time comes and it decieds its tired i will rebuild it. the 4108 is a simple engine with no rubber timing belts to snap on you just solid steel gears unlike the more modern engines, and now they have redesigned the rear seal and can suppy you with one that wont leak unlike the old ones markus

[beneteau-500]

G'Day Frank I have just this year done my first rebuild on my perkins 4.236 engine and i would never consider getting rid of it and replacing it . It had done 9500 hrs before i did this rebuild the cost of the rebuild came too 2000 euros labour 650 euros in engine parts and 500 euros for new g/box heat exchanger and engine heat exchanger.

and the only reason i did the rebuild was because the water way's in the block where starting to grunge up

[Stillraining]

My vote goes for a rebuild....Parts are numerous and there are many rebuilt engines of that model sitting on shelves ready to go if you just wanted to swap out and let someone else actually do the dirty work...It is fun and educational though so if your up to it I highly recommend it.
I would have to think very hard about my 4-154...it was Perkins "Odd Ball" engine and parts are becoming like hens teeth.

[Randyonr3]

I went throu the delima of replace/ rebuild my 4-108 a couple years ago.. leaking oil like crazy.. found the plastic sending unit under the starter had cracked and 98% of the oil was comming from that leak..
Durring the time I did a little research on the 4-108.. seems only about 6% were used in the Marine industry.. they are normally used in the farm equeptment and pumps.... dont be surprised if you see a fire truck with a 4-108 being used as an aux-pump for water, or to see a local tractor with a 4-108 in it..
I found the 4-108 is still being sold by tractor companies and most have all the parts needed to rebuild the motor

[smilie]

I have a 4-107. Oil leakage is a pain. Has been costly to rebuild (twice! in 3 years). Go new if you can afford it but I really don't know much except from my own experience.

[beneteau-500]

smilie if you have had to rebuild twice in three yrs then you havent had the rebuild done properly yes like all engines you get leaks of varying degrees from time to time and can be fixed as long as it is done correctly and as long as you have really Identified the cause of these faults