Date: December 1, 2015
From: Kaj-Mikael Wredlund
I have an Endeavour 40 with a Perkins 4.108. It has 2,800 hours on it and it runs fine but is leaking oil from both ends of the crankshaft. I would like to hear from other owners who may have had this issue and is looking for advice on a remedy.
Date: December 1, 2015
From: Carl Hibbard
Make sure crankcase ventilation system is open.
Rear seal is a rope seal.
Front seal is a lip seal.
Else perhaps overfilled
Date: December 1, 2015
From: Phillip Johnson
One of the techniques I have seen on 4-108's is the use of a Walker air separator filter which puts the crankcase under a slight negative air pressure (vacuum) this causes the oil in the seal area to be drawn back into the crankcase. I hope this helps you.
1981 E40 hull #114 owner for 26 years.
<Date: December 1, 2015
From: Bill Mintz
Perkins are reliable old engines. And they leak. The rear seal is in 2 pieces and can be serviced after removing the transmission. Not too rough on the Endeavour 40 as access is good from the aft cabin. The front seal is tougher and requires quite a bit of year down. If it's not awful I would put down an absorbent pad and keep an eye on the oil level. In another 2,800 hours it will be time to rebuild the engine. Do it then.
Been there.
Date: December 1, 2015
From: Keith Buller
This is typical of the 4-108. I had my rear main wax ring seal changed at about 2,000 hrs. Time did it in! Cost me about $1,800.00 and took my mechanic about a week with my help. She stopped leaking though. In his mind it was a mercy save for the motor but it still runs strong and I am confident it's push us around for many more years. If you would like to contact my mechanic just let me know.
Date: December 1, 2015
From: Fred Lowe
Perkins makes a after market kit that will stop that without having totaling the motor apart.
Date: December 2, 2015
From: Fred VerPlanck
I can't speak to the forward crankshaft seal, but the rear seal is a horizontally split seal. It can dry out and leak. I fixed our Perkins 4-108 aft seal leak with a bottle of Gunk or Bardahl or brand "X" seal softener added to the crankcase oil. It was a very inexpensive fix that solved the problem. Twelve years later . . . no leaks.
Try it before resorting to more expensive remedies.
Date: December 2, 2015
From: Ismet Bayyurt
I have a 1981 Endeavour 37 with the same engine and problem at the end of the shaft—the problem is the crank shaft seal. This engine is very reliable at sea but has a bad reputation about oil leakage. It should be repaired but after a year you may have the same problem again.
You can put an oil pan under the leake and collect it or you can make a by-pass to the bilge and drain off the oil into a canister.
Regards from Turkey
Date: December 2, 2015
From: John Creecy
2800 hours is not high, the crankshaft oil seals should not be leaking yet. The most likely source of the leaks are the seals at either end of the sump pan (oil pan). The sump may have been removed for some reason in the past and not replaced carefully. You can check this by cleaning behind the front pulley then run the engine, you will see if the oil is leaking from the crankshaft oil seal or the sump gasket.
If the sump is leaking you need to remove the pan and replace the gaskets and seals. The square section seals have to be carefully cut to length and glued to the bearing housings before replacing the oil pan. Its not an easy job with the engine in the boat but do-able with care.
We had a Perkins 4-108 engine on our Morgan Heritage with over 3,000 hours, it leaked oil from both ends, I replaced the sump gaskets as above then no more oil leaks for another 8 years.
Good luck