Perkins 4-108 oil leaks solved

[TKDSailor]

Originally Posted by Capt Gill

I agree with Z, maybe not all Perkins leak, however, when 99%(anecdotally) of those Brit engines leak to say "all" is ok. Maybe you had one of the exceptions – for awhile! I've had many Brit cars and one m/cycle, a Norton, in my time and can't recall a one that didn't leak oil; I used to have an auto shop and one of the quips we'd make re. Brit engines is, "if it's not leaking it's probably out of oil", one even tends to supernaturalize to explain the issue as I have with my Perkins 4-108, this can also apply to you, it's the Gremlin theory, i.e. the Gremlin(s) is/are embedded in the boat, one can't get rid of it w/o destroying the boat so you learn to live with it and appease it, e.g. in our case, the Gremlin is residing in the Perkins, so ya fix the leak, however the Gremlin relocates and the engine leaks elsewhere (remember, can't get rid of the Gremlin it only relocates). In my case, I've resigned to accept this as fact, so we get along ok as long as I appease the Gremlin, although the engine still leaks it's v. little and manageable; you may ask, "how does one appease the Gremlin?" well, this works for me: the Gremlin is at its best behaviour when given a clean, tidy environment and proper maintenance. Of course, since perfection is not possible, the Gremlin will let its presence be known, e.g. the same oil leak that wasn't fixed properly the first time or something else that has been neglected. The Gremlin also has times when it's evil, vindictive or just out of sorts and will cause problems that have nothing to do with you, in that case, it's best to take a deep breath then go about what needs to be done to remedy the issue, try to refrain from getting angry, yelling at your mate or kicking the dog as this will provoke the Gremlin, it sees this as a weakness so steps up the game, perhaps by sabotaging the work such as allowing a unique piece of hardware to slip from your hand into the hinterland of the bilge,but the trick is to maintain a calm attitude take a break if need be, that will keep the Gremlin at bay as you're no longer any fun. If this all sounds a bit anthropomorphic so be it, however, I think most of us can recall a time when we struck, banged on or spewed epitaphs at the object of our frustration, if so you're being Anthropomorphic.
Seems like you've come to terms with your "awesome" Perkins as I have, so much so that I'm going to give it a first name, any ideas? Maybe Anthony?

LOL! Good luck with Anthony! We've followed similar paths; my first bike was a Norton Atlas, with that wonderful Featherbed frame... I used to use it as a scrambler off road, as it handled so well. Unfortunately, as the pistons both went up and down at the same time, it vibrated so bad that things would fall off it as I went down the road... I went to school and became a motorcycle mechanic, fixing rice burners and brits (yeah- 3 sets of tools- Whitworth, Metric and English...). Our 1974 MGB did leak, but the saying was,"Lucas igintion, home before dark..." And, living on the island of Gloucester, MA, it eventually rusted so bad that the Unibody sagged in the middle...

I'm definitely going to try re-bedding the timing cover, to see if that helps... I have really beat up that engine, overheating her a few times, putting gas in the diesel tank (not my fault), etc. and she still runs beautifully. I think I'll name mine Sheila...

[Capt Gill]

Originally Posted by TKDSailor

LOL! Good luck with Anthony! We've followed similar paths; my first bike was a Norton Atlas, with that wonderful Featherbed frame... I used to use it as a scrambler off road, as it handled so well. Unfortunately, as the pistons both went up and down at the same time, it vibrated so bad that things would fall off it as I went down the road... I went to school and became a motorcycle mechanic, fixing rice burners and brits (yeah- 3 sets of tools- Whitworth, Metric and English...). Our 1974 MGB did leak, but the saying was, "Lucas ignition, home before dark..." And, living on the island of Gloucester, MA, it eventually rusted so bad that the Unibody sagged in the middle...

I'm definitely going to try re-bedding the timing cover, to see if that helps... I have really beat up that engine, overheating her a few times, putting gas in the diesel tank (not my fault), etc. and she still runs beautifully. I think I'll name mine Sheila...

Sheila, I like that <https://youtu.be/5xb1z2V1z7k>, think I'll go with Tony because of the dark role TP played in the film Psycho.
The Commando somewhat cured the vibration problem with the Isolastic anti-vibration system developed by a former Rolls-Royce engineer, all the same, I blame that bike with its 10:1 compression and occasional cranky refusal to kickstart for the onset of my sciatica. My next bike was an "84 BMW R100 (which I still have)- push the button, starts every time. All the same, I did love the thrill of the Commando's torque when opening the throttle! The 850 introduced an elect. "assist" starter, assist meaning don't count on it. Yeah, Lucas AKA "The Prince of Darkness".
A novel approach to solving Perkins oil leaking, assuming the obvious leak issues are resolved, is a kit that works somewhat like a cars gas engine's PVC system, except the vacuum hose is connected to the crankcase, not the v/cover i.e. if the crankcase has positive pressure (checking at the dipstick tube) at cruising RPM then by installing this system it will create a neutral or negative pressure and ,in theory, prevent oil from being forced out through seals and gaskets. West Marine used to sell the kit. My friend has it on his Perkins and says it solved the oil leaks.

[SSgtPitt]

The more I read this the better I feel. My 4108 leaks like all the rest. The diapers help but the leaky stuffing box eventually fills the sump which then eventually overflows into the bilge which eventually means I’m vacuuming, disposing of nasty oiley salt water and scrubbing everything w 409.....only to have to start all over again in a few weeks.....frustrating. The longer I’m on the boat the better I get at figuring it out.

[jfhspike]

Here's a tip if you're thinking (or someone else reading this later is thinking) about replacing the rear oil seal...(which is where almost ALL 4-107 and 4-108 engines leak). You might say to yourself "maybe I should get something that doesn't depend on a cotton-asbestos(?) thing wrapped around a stiff wire, which has to be trimmer to exactly the right length to make things work," and decide to go with Foley's fancy fix at a cost of about $120 (!) -- http://www.foleyengines.com/product/...rear-seal-kit/.

You could, instead, order a similar upgrade kit from parts4engines, namely
http://www.parts4engines.com/perkins...l-upgrade-kit/ for $32.

which you'll notice comes with the gasket for the seal-housing (which you're going to destroy when you try to remove the old seal anyhow), not to mention the tab-washer you'll need when you want to replace the flywheel.

While you're at it, you can buy a full bottom-gasket set (which you'll need if you go all-out and drop the pan in an attempt to fix further leaks): http://www.parts4engines.com/search....ection=product. That's $45.

Pick 2-day shipping for $24, and even with the VAT, your total is $101, and if you're as lucky as I was, the parts will be on your doorstep 1.5 days after you order them.

Compare this to the Westerbeke cost for just the pan gasket ($118 from Marine Diesel Direct, who aren't allowed to sell it to me because they're in the wrong "region"...sigh), and suddenly that price looks pretty darned good.

[ronieboy91]

Hi.
Iv got a big problem with either water or oil entering the oil pan in my Perkins 4108 engine. The oil is a milky sort of colour and very thick. I have been trying to sort the problem for about a week now and still can't resolve it. Iv got the oil cooler tested, it was sound and even put a new one in and it's still leaking in. Iv tested the lift pump, it was sound also. Iv bipassed the oil cooler just to double check it it's still mixing. I have a fairly experienced mechanic working on it and he is even puzzled. The fresh water in header tank level is not going down so I think this rules out the head gasket does it? I'm just wondering if anyone could give me any other suggestions as to what the problem might be?
Any help would be greatly appreciated.

[jfhspike]

Originally Posted by ronieboy91

Hi.
Iv got a big problem with either water or oil entering the oil pan in my Perkins 4108 engine. The oil is a milky sort of colour and very thick. I have been trying to sort the problem for about a week now and still can't resolve it. Iv got the oil cooler tested, it was sound and even put a new one in and it's still leaking in. Iv tested the lift pump, it was sound also. Iv bipassed the oil cooler just to double check it it's still mixing. I have a fairly experienced mechanic working on it and he is even puzzled. The fresh water in header tank level is not going down so I think this rules out the head gasket does it? I'm just wondering if anyone could give me any other suggestions as to what the problem might be?
Any help would be greatly appreciated.

Well...milky oil sure suggests water in it. There doesn't need to be a lot to turn it milky. There are two kinds of water around (assuming your boat's in the ocean): salt and fresh. Salt water comes into the raw-water pump, up through the oil-cooler, into the heat exchanger, and out the exhaust. I suppose that if the raw water pump seal is completely shot, you could be getting lots of salt water running from the back of the pump into the engine...but it should be coming out the "weep hole" in the bottom of the raw-water pump before then and be really obvious. You could check that the weep hole isn't somehow clogged --- take a drill-bit and run it up into the hole gently turning by hand to clear out any muck.

Salt water getting in at the oil cooler? You've eliminated that.

At the heat exchanger? There's only salt and coolant in there, no oil, so presumably that's not a problem.

AFTER the heat exchanger? I suppose that where it gets pissed into the exhaust loop might be somehow backed up or otherwise messed up so that you're getting salt water back into the exhaust, which then runs down the cylinder walls into the engine sump. But you'd expect that to be a problem that might cause a water-lock so that you couldn't turn over the engine, etc., so it seems unlikely.

So now I'm thinking "it's probably coolant." Maybe just a little, maybe a lot. But one quick check is to loosen the oil-drain plug and let just a few drops of stuff come out. Even if there's coolant emulsified in the oil, there'll probably be some sitting at the bottom of the sump, too, and it'll drip out first, because oil floats on water. So put a paper towel or 20 under the sump, ease out that screw until a few drops come out, and see what's there.
(example: see this video:

https://www.youtube.com/watch?v=2tNYb0V5-U8

) If what comes out looks greenish (assuming that's the color of your coolant!) you've got your answer.

It sure seems as if coolant is the more likely culprit, now that you've decided it's not the oil cooler.

Best of luck on this.

[ronieboy91]

Thanks very much.
Yes I thought about that but the engine is turning fine and is running very smoothly aswell so if there was water getting in up around the Pistons she wudnt turn as well ryt? And she wudnt be running so well. Ok if it's coolant then wudnt it be emptying the header tank? The level hasn't dropped at all and the sump is filling up at a very fast rate, like it goes from the min mark on dipstick to the top after running it for 20 mins?! It's an awful headache this.
Thanks again for your help.

[ronieboy91]

Sorry also I can't get to my sump plug because it's too tight to the bottom of the boat. Iv had to drain it with a vacuum pump and even crank it out through the filter cos the stuff that's coming out is too thick to suck out

[MarkSF]

[QUOTE=Ecos;2445245]

Originally Posted by UNCIVILIZED

So then the same people that built fighter planes out of wood.


They were not fighter planes, they were bombers. They had 2, a big bomber and the Mosquito. Just about biggest plane we ever built was wood. Wood is just about the strongest composit there is. The oil leak is not the mounting plate, it's the timing gear cover.

The salient point about wood there, is not about it's quality as a material for building planes out of.

The point was that, at the time, all the factories capable of making metal planes were running at full capacity. The Mosquito etc. could be made by workers that were experienced in working with wood - thus it was extra, bonus, manufacturing capacity.

[rbk]

Most likely culprit to check is your raw water pump (front of the engine and either bronze and shinny or that large mass of green and white fuzz you’re not really sure what it is). The double bearings end up leaking water back into your timing cover and mixing with your oil.

[jfhspike]

I agree -- if you're getting a quart of new liquid in the sump in not-too-many minutes of running, it HAS to be salt water, because otherwise you'd be losing about half your coolant supply at the same time. And if it's not coming in through the oil cooler, it's gotta be coming through the raw water pump.

The good news is that it's pretty easy to pull the pump -- remove two hoses, undo four 1/2 or 9/16 nuts, slide the pump off its studs. The next piece of good news is that those parts-4-engines folks have a rebuild kit for it that's not too expensive (https://www.parts4engines.com/perkin...-service-kits/). OK, so the overhaul kit...it'll set you back $100 bucks, plus the VAT and shipping...say $150. THat's a lot less than you'll be paying your mechanic. And it gets you a new shaft, the bearing and two seals, a new cover plate (worth its weight in gold, because it'll let you keep the old one as a spare), etc.

The bad news is that it's only the right service kit if your pump looks like this: https://www.parts4engines.com/perkin...aw-water-pump/ (6 screws on the cover plate gives it away); the part number is JABSCO-3270-0001. New pump is about $430 from maringpartssource; service kit from them is about $45, but doesn't include the new shaft or cover or the alignment tool.

The alternative is the Jabsco G65, whose cover has four screws, with a pricetag of $550 (!). Marine-parts-source sells a rebuild kit for that (bearings, seals, spare impeller) for $98, but that doesn't get you a new shaft or cover either.

Definitely check the weep hole. There should be at least one, and probably four, located around the shaft roughly where the red arrow is pointing in the attached diagram. As I said, use a toothpick or drill bit to clean it out, and then watch for water pouring out through it when the engine's running.

I'm betting dollars to doughnuts you'll see it coming out there (and as a result, you'll be getting less into your sump!), and you'll know what to do next.

[jfhspike]

By the way, it worries me a little that your mechanic hasn't thought of this route for water-entry. It's possible he's not as good as you think he is. [Sigh.]

[rbk]

Originally Posted by jfhspike

I agree -- if you're getting a quart of new liquid in the sump in not-too-many minutes of running, it HAS to be salt water, because otherwise you'd be losing about half your coolant supply at the same time. And if it's not coming in through the oil cooler, it's gotta be coming through the raw water pump.

The good news is that it's pretty easy to pull the pump -- remove two hoses, undo four 1/2 or 9/16 nuts, slide the pump off its studs. The next piece of good news is that those parts-4-engines folks have a rebuild kit for it that's not too expensive (https://www.parts4engines.com/perkin...-service-kits/). OK, so the overhaul kit...it'll set you back $100 bucks, plus the VAT and shipping...say $150. THat's a lot less than you'll be paying your mechanic. And it gets you a new shaft, the bearing and two seals, a new cover plate (worth its weight in gold, because it'll let you keep the old one as a spare), etc.

The bad news is that it's only the right service kit if your pump looks like this: https://www.parts4engines.com/perkin...aw-water-pump/ (6 screws on the cover plate gives it away); the part number is JABSCO-3270-0001. New pump is about $430 from maringpartssource; service kit from them is about $45, but doesn't include the new shaft or cover or the alignment tool.

The alternative is the Jabsco G65, whose cover has four screws, with a pricetag of $550 (!). Marine-parts-source sells a rebuild kit for that (bearings, seals, spare impeller) for $98, but that doesn't get you a new shaft or cover either.

Definitely check the weep hole. There should be at least one, and probably four, located around the shaft roughly where the red arrow is pointing in the attached diagram. As I said, use a toothpick or drill bit to clean it out, and then watch for water pouring out through it when the engine's running.

I'm betting dollars to doughnuts you'll see it coming out there (and as a result, you'll be getting less into your sump!), and you'll know what to do next.

Sherwood G65 not Jabsco.

[BigAl.NZ]

Originally Posted by sv.antea

photos, one of bedding down the front plate, the other: after the timing cover went on

SV.Antea - we are looking to do the same mod. IIRC a few months ago when I was researching this I found that later Perkins 4108 either had a mod (like the one you made) or a newer version of the timing cover that was more rigid.

I now can't find any information on the later version of the timing cover - nor this plate I thought was available.

Did you ever come across this newer cover/plate?

Cheers

Al