Westerbeke 4-107

[MarkRoadley]

Recently acquired my Clipper 36, which has a Westerbeke 4-107. A couple of questions to any experienced Westerbeke/Perkins owners:
1) Can anyone assist me in determining the manufacturer's date from markings on the engine

2) I was told "in passing" by a marine diesel mechanic, that the 4-107 which is on my boat has a "split" main seal between the engine and trans, which tends to leak oil. And that the 4-108 solved that issue by redesigning and using a full rubber seal as are found on later model car engines. Can this be confirmed or commented on by anyone here?

Thanks

Mark

[SloopJonB]

Originally Posted by MarkRoadley

I was told "in passing" by a marine diesel mechanic, that the 4-107 which is on my boat has a "split" main seal between the engine and trans, which tends to leak oil.

It's British - of COURSE it leaks oil! It will also run nearly forever if you take care of it. Put a drip pad under it and keep on truckin'.

A guy I knew in San Francisco called himself an obsolete marine engine specialist. He told me he had seen Perkins 4-107's running water pumps in the vineyards in Napa that had 40,000 hours on them. Of course they ran continuously under optimum conditions but 10K is commonplace in boats.

YMMV.

[MarkRoadley]

YMMV

I appreciate your wit - thanks. I've owned British sports cars and understand. The previous owner actual had a stainless steel drip pan patterned to fit the shape of the bilge.

Mark

[Rick486]

I had a 4-107 in my P39 yawl for about 13 years and it ran fine, always started, and never let me down. But it dripped oil from the bottom of the bell housing. I re-powered her with a Perkins 4-108 brand new and factory fresh since it was basically a bolt on. Guess what. Dripped oil from the same place. Another great engine, always started, ran fine, but dripped oil. Live with it.

[PorFin]

Mark,

As others have mentioned, the Perkins 4.107/4.108 series have proven themselves to be very reliable (but not perfect) engines. Our 4.108 is pretty much "Old Faithful."

Originally Posted by MarkRoadley

A couple of questions to any experienced Westerbeke/Perkins owners:
1) Can anyone assist me in determining the manufacturer's date from markings on the engine

I don't know about the Westy versions, but Perkins has an engine numbering protocol that does indeed give production year and location. You can find it here.

Originally Posted by MarkRoadley

2) I was told "in passing" by a marine diesel mechanic, that the 4-107 which is on my boat has a "split" main seal between the engine and trans, which tends to leak oil. And that the 4-108 solved that issue by redesigning and using a full rubber seal as are found on later model car engines. Can this be confirmed or commented on by anyone here?

This is not quite accurate. Like the 4.107, the standard rear main on the 4.107 is a split seal. This was a design feature that allows the seal to be replaced without needing to remove and disassemble the engine. The trick (from what I've read -- I've never replaced one myself) is in getting the two halves of the seal cut to the exact lengths (and we're talking thousands of an inch here) that will develop a optimal seal.

I think what the mechanic had in mind was an after market conversion that is marketed by Foley Engines, details of which you can see here. I've never seen actual independent customer feedback -- either good or bad -- on this particular seal. Foley claims it's the best thing since sliced bread.

Having said that, if you search the internet you'll find a whole tribe of unhappy Foley customers. I've never dealt with them myself so I have no personal experience with Foley (and based on the comments of those tribe members, hope I am never faced with the need to do so.)

Hope this helps,
PF

[BELLATRIX1965]

Hi: I agree with the previous posts. Since you have a SS drip pan under your engine, just live with the rear main seal leaks, place and change an oil-absorbent "diaper" under the engine regularly. This is what we do with our c. 1965 4-107. There is NO magic bullet to completely stop rear main seal leaks in these engines!

These engines are strong and reliable. The Achilles heel of the 4-107 is the fact that the cylinder liners are wet, with o-rings to seal the water passages between the block and the liners. When the o-ring lands inside the cylinder block corrode and fail, then the engine is toast. Until that happens, don't let anyone talk you into buying a new engine!

As previously stated, ALL Perkins 4-107 and 4-108s had a split rear seal.
BEFORE you even think about dealing with "Dr. Diesel" at Foley Engines, do yourself a favor; search these threads and read all the horror stories!

Trans Atlantic Diesels in Virginia TAD for perkins engines, perkins diesel, perkins marine, perkins parts, perkins generators, perkins service is an honest, reliable source for parts for your engine. (I am just a customer - no financial interest).

Your serial number can be found on top of the engine block, right above where the high pressure fuel injection pump bolts on. I lifted this from another site, and the info is accurate:

quote "The date of manufacture can be roughly determined by the serial number. Three systems of engine numbering have been used. The earliest engines had a serial number consisting of seven digits. The 4/108s were 73XXXXX, the 4/107s were 71XXXXX, and the 4/99s were 70XXXXX. On engines built during the early 70s the serial number was changed to include letters and figures. The number started with three digits giving the engine type, i.e., 108, 107, or 99, then a letter marking the country of manufacture, and finally several digits showing the order in the production run. My Perkins 4/107, made in 1974, is numbered 107U43112. Engines built in the late 70s and after carried an alphanumeric serial number of up to 15 characters showing the engine family, the specific engine type, the parts list, the country of origin, the production number, and the year of manufacture. A typical serial number might be ED1534U510256D. The last character, showing the manufacturing year, is a letter. B represents 1975, C is 1976, and so on through the alphabet. Letters I, O, and Q are not used." unquote

Happy Motoring!!

[MarkRoadley]

Excellent feedback from all of you. I really appreciate you sharing your experiences and knowledge

Then engine dating is so I can determine how long she's been in service and what tech manuals I'll need to obtain.

I'm a fair gas engine wrench turner, and I think I was looking for an excuse to get my hands dirty on a diesel for the first time. I'll be looking at all the links you have provided and do the usual research. Probably going to pull the engine, if for nothing else, to clean and paint her.

Many thanks guys (and/or gals).

Mark

[WanderingStar]

You'll be fine with repairs. I bought a manual on ebay, ( for Perkins) they can also be found online, I think at the Cape Dory Owners's site. I do all my own repairs with that manual and a couple of standard marine diesel repair books. My only training is 30 years of fixing my cars. And I love my '68 4-107.

[PorFin]

Originally Posted by BELLATRIX1965

Trans Atlantic Diesels in Virginia TAD for perkins engines, perkins diesel, perkins marine, perkins parts, perkins generators, perkins service is an honest, reliable source for parts for your engine. (I am just a customer - no financial interest).

+1 on TransAtlantic Diesels. They've always treated me right, and I've yet to see or hear ANY negative feedback from TAD customers. They are exactly what Foley apparently is not: Friendly, responsive, honest, patient, knowlegable, etc, etc.

[BELLATRIX1965]

Originally Posted by WanderingStar

You'll be fine with repairs. I bought a manual on ebay, ( for Perkins) they can also be found online, I think at the Cape Dory Owners's site. I do all my own repairs with that manual and a couple of standard marine diesel repair books. My only training is 30 years of fixing my cars. And I love my '68 4-107.

The Perkins shop manual is actually on the Islander 36 site - you don't need to buy it!

Check it out here: (6.6 megabytes) www.islander36.org/Perkins%20Shop%20Manual.pdf)