Perkins 4-108 vs Westerbeke 4-108

[world spectator]

I have a late 70's Pearson 365 with a Westerbeke 4-108, I would like to replace it with a mid 80's rebuilt Perkins 4-108 - same block and foot print however I have a couple of concerns. The Perkins has a different heat exchange unit and exhaust system which needs to be changed or modified for my Pearson. The Westerbeke engine is mounted backwards and connected to a V-Drive the exhaust exits towards the front of the engine, therefore it goes to the muffler (approx 24") in a direct line with one elbow and then out the transom. However on the Perkins, the exhaust manifold is reversed and exhaust gas and water exits towards the rear of the engine which in this case will be approximately 60" from the muffler, towards the centre of the boat and is to low down so that it will need to have some type of modification to raise the height of the exhaust elbow allowing a dry loop as per the exhaust system as per the manufactures specifications. Has anyone done this or does Perkins make a water jacket/exhaust system the allows the water and exhaust to exit in the opposite direction. Or can the exhaust/water jacket and exhaust manifold be swapped with the one on the westerbeke, will it fit? is it the right size or does it require modifications?

[CSY Man]

Can't answer yer question, but have a comment:

Never heard of a Westerbeke 4-108..Only Westerbeke 4-107.
(I had a W 4-107on previous boat)

Present boat has a Perkins 4-108, there is also Perkins 4-107s, I belive the difference between the 2 Perkins models is the sleeves...(?)

Lots of different versions of the 4-108 with heat exchangers and water tanks, etc in different location.

(Old style, new style, low style, this and that style)

Good engine, I love make Perkins 4-108.

[TrevC]

We have a westerbeke (4107? I assume) bottom end with a perkins 4108 top end, on a Pearson 365. I'm also from Winterpeg.... weird!

We have a customs SS exhaust elbow to make the fit, not sure if that helps you at all. If you have specific questions just PM me.

Also, the westerbeke heat exchangers seem pretty crappy (rubber end cap and all). You can buy very nice, new american ones from Sea Kamp engineering. They're a great source for oil coolers, heat ex, etc.

We just finished a big maintenance session here. New heat ex and oil cooler, all new hoses and exhaust elbow. Fixed up the gear box. Runs great.

[CSY Man]

Good engine, I love make Perkins 4-108.

Uh, that was a Fraudian slip...

I don't make love to my Perkins, but I love it..

(Have considered a bumper sticker saying: "Have you hugged your Perkins today?")

[TrevC]

My apologies, I had that mixed up. We're a Westerbeke top-end and Perkins bottom-end.

[lancelot9898]

Originally Posted by TrevC

Also, the westerbeke heat exchangers seem pretty crappy (rubber end cap and all).

I have the Perkins 4-108 with the rubber end caps on the hx and it's still going strong after 25 years. I think it's a bowman hx and a Perkins mechanic told me that there is no zinc in that exchanger due to the rubber end caps isolating the hx from the rest of the engine. The metals in that exchanger must be all pretty close on the galvanic scale for that to work, but for 25 years it has in a salt water environment.

[TrevC]

Just curious... how would that isolate it? I thought the Zincs were also there because sea water flows through the copper (stray current in marinas, etc)

I'm fairly certain our rubber-capped heat ex had a zinc, too.

The new one has a connection for a ground wire, which we have yet to attach. The old one didn't.

[lancelot9898]

The rubber end caps would isolate the hx from the other metals contained in the engine.

[OaklandSailor]

Experienced Opinions Sought:

I am looking at a P365 with Westerbeke 40 & v-drive. My question is whether or not this setup is a seriously negative point and so a boat with v-drive should be avoided altogether? I will see the boat soon but I've read either here or at sailnet that the engine access on the 365 is very limited and that this may also reduce the desirability of the boat.

Does anyone know from experience or maybe a close sailing buddy with this setup?

Thanks,
OS

[zeehag]

how does that 107 and 108 mix work out?? i have westerfreke 107 parts left over from changing out my blown red 107 and repowering with a nice, smooth purring perkins blue 108. i love my 108. is awesome--burly .. i used some parts--so i have red pox on my blue baby, but she is awesome--but i still have red's parts....i didnt realize they could be usable???

[TrevC]

Apparently they are. Works just as well as any other Perkins 4108 (leaky and loud!). Ours is all Red. The angry colour suits the noise

The V-drive appears to be a very simple mechanism. I can't imagine it resulting in many problems. The added complexity isn't great, but it does help bring the engine further forward in the boat (less weight at the bow/stern is always good), and it increases ease of access for maintenance by also tilting the engine slightly forward. I'm not sure how access would be considered "limited". I don't have many other boats to compare to, but I'd guess it's still probably above average.

I'd be more concerned about the Paragon SA0 gearbox that Pearson liked to use. The reverse mechanism is an absolute joke. I bet this thing wasn't a good idea in 1979, and now it's just an old bad idea. If I was shopping now, I'd be looking for a P365 with a Borg Warner hydraulic gearbox, preferably a newer one (there's a model that's nearly drop-in compatible).

If I had my way I'd rip everything out from the engine down to the prop. Oooold technology, yuck.

[Jesse]

The Westerbeke externals will bolt right up on the Perkins. It is essentially the same engine with a couple internal differences that wont effect your project in the least. Simply remove every external part , including the drive plate and flywheel and put them on the 4108 and re install it. The starter, alternator, hoses and clamps might need refreshing too. It's a project that requires close attention and a bit of time but well worth it.

[zeehag]

my starter alternator and such , as the 4-107 had fewer than 100 hours on it when it was terminated from earth in a rocketship, are all in use on my new blue--i just didnt know the heads were also usable!! wow i got spares!!!! hooyaaahh!!!!

[IceMan]

The Westerbeke basic engines from the 70's and 80's were bought from British Leyland in the UK and Westerbeke dressed them up with their accessories and parts. These are the same engines that are in the old black taxi cabs you see in the old movies from England. Somewhere in my email I still have and address for a British Leyland salesman in the UK. Their parts are about 1/5 maybe even a less than Westerbeke parts here in the U.S. An injector for my 60 hp engine is or was 67 pounds last year. Cheers
WD

[zeehag]

the main difference is the marinizing. there is only slight difference between the two marinizing companies.