Taiwanese is rough seas and caribbean crossings?

lostviking wrote:
Is there any way to upgrade the Injector on the FL120 so it does not need frequent oil change?

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Yes there is. It's not an upgrade per se but an accepted manner of plumbing the pump sump to the oil system on a home-made basis.* The "conversions" I've seen photos of connect the injection pump sump to the oil line coming out of the oil filter and then back into the lube oil heat exchanger (or something like that).* I've only heard of a few people doing this.*

One knowledgeable and experienced fellow in the UK who's on the GB forum who restored a wood GB32 that had this modification on its FL120 changed it back to the stock system because he felt the stock, self-contained sump did a better and more reliable job of lubricating the pump's drive mechanism (the lube oil does not lubricate the injection plungers in their bores--- the fuel does that).

Since the pump oil change is so easy and quick I've never had any motivation to explore changing ours other than to know that it can be done.

lostviking wrote:
Every 50 hours seems good. It is only every 6th day or so if only doing long legs in daylight.

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The reason for the 50 hour oil change requirement is that it's the nature of a jerk-injection fuel pump-- which is what the CAV/SIMMS/Minimec inline injection pump on an FL120 is--- to over time wear its injection plungers and the bores they run in.* As the bores and plungers-- which have a very tight clearance because this is what provides the pressure for each injector "shot"--- wear they allow a bit of fuel to leak down past them on every stroke.* This fuel leaks down into the lube oil in the sump below the injection bores and dilutes the lube oil.* The more diluted the lube oil, the less lubrication it provides, and the more wear can occur in the pump's drive mechanism.

The more the engine is used the more the plungers and bores wear and the greater the volume of fuel leaking down becomes.* This, by the way, is why lubricity in the fuel is so critical to older diesels with these types of injection pumps, plus the fuel also lubes the moving parts in the injectors themselves.

Eventually the wear and subsequent leakage become severe enough that they begin to affect the ability of the plungers to produce the right injection pressure and the engine's efficiency and smooth running starts to suffer.* At that point, it's time to have the pump overhauled, a not-inexpensive proposition.

But up to this point, fuel has been getting down into the lube oil in gradually increasing quantities and diluting it.* A newly ovrhauled pump will not leak at all, and one that is nearing the need for an overhaul will leak a lot, with everything else somewhere in between.* The 50 hour oil change interval was selected to make sure that no matter how much oil dilution may be occuring with a pump that is still operating within the acceptable injection pressure range, the oil will not become so diluted as to start posing a threat to the pump's drive mechanism.

Wow. This was insightful.
Now I will not mess with the service interval or do any thing funny to the oil filter.

On the used boat there is a huge different on the photos of the engine bays. Some look like brand new after 40 years and others look like they come from a salvaged ship.

How thoroughly is it possible to damage the engine with 40 years of misuse?
What should I look for when I am going to select a boat. (before i call engine survey guy).

You can damage an engine with fifteen minutes of misuse. I believe it is a mistake to try to equate engine condition with age. Our engines were apparently operated and maintained correctly by the four or five previous owners of the boat because today, 39 years after they were installed by the factory in Singapore, they use less than a quart of oil every 100-150 hours, they smoke only on startup (which if they don't there's something wrong ), and they fire right up with no hesitation on the first turn of the starter assuming the ambient temperatures are not super-cold. They're not going to run like this forever but they're running like this now.

And we all know people who have had problems, maybe major ones, with engines that are relatively new.

I would say that if someone is operating a boat's engine in an abusive way, it may not make five years before needing major work let alone forty.

Low hours is not a guaranteed indication of an engine in good shape. A thirty year old engine with only a couple thousand hours or less on it can mean one of two things. One, the boat was used fairly frequently but only for pretty short trips. This was the case with our boat which spent its whole life on San Francisco Bay before we bought it. The boat was used frequently enough but distances are relatively short on the bay and up the river. So lots of short trips, low time on the engines.

Versus number two, which is the boat sat around a lot without being used. Unless the engine is properly pickled, this can be much worse for an engine's condition than being used. Given the choice between an engine with 8,000 hours of proper operation and maintenance in a boat that was used regularly and the same type and age of engine with 1,500 hours on it in a boat that was used very infrequently, I'd take the boat with the 8,000 hour engine all else being equal.

You speak words of wisdom Marin.

I guess I just need to look at factors like how clean it is. If it is any visible rust, corrugation, oil spots ect. Obvious things.

I have some hobby mechanic skills for landrover engines, but that is not so voluntarily, haha!
I guess I will learn the engine after a while anyway. I still want to though.

Is there a kind of "haynes manual" for those kind of engines?

Haynes is ingenious!

Greetings,
Mr. lostviking, I fully agree with Mr. Marin. To me, a clean boat/engine/engine room is an indication that at least SOME maintenance has been done in a timely fashion*but that does not avoid the necessity for good surveys.

** You say you have "hobby mechanic skills".* Well, those will serve you well.* A fan belt is still a fan belt and an oil change is still an oil change.* Before I "adopted" the current vessel, I had NEVER worked on a diesel engine but short of getting into the "insides" of one, have been able to fix everything that's come up so far.


-- Edited by RT Firefly on Tuesday 28th of February 2012 05:19:59 PM

Great!
I can change oil and fan belts.

Trouble arises when I hear funny sounds, hehe!

On a single engine at sea that might be a bad thing, so I want to prepare as good as I can.
Do any of you have a list on filters, oil quality, tools ect. who is recommended to have at all times by trawlers?

In a car I can manage to have engine troubles I cant sort out at the spot, but at sea I want to be able.

On the Ford Lehaman 120, you have to remove the water hoses to replace the belt,I have two extras that I have allready inside the hoses ,zip tied to here and there,so I dont have to Loose any hoses. Losen the alternator, Slip the new belt on, off you go. BB

Greeting,
Mr. lost viking...For those "awkward" times you're caught short...********* http://www.boatus.com/Towing/


-- Edited by RT Firefly on Tuesday 28th of February 2012 06:25:49 PM

lostviking wrote:Is there a kind of "haynes manual" for those kind of engines?

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Not that I'm aware of.* However most engines will have had a service and parts manual available as well as an operators manual.* We have both the parts and Ford service manual for the FL120 on our boat.

One thing to be aware of, however.* A diesel engine is not like a car engine of the same vintage.* A 1950s-1960s automotive gas engine is a very simple piece of equipment with a carburetor and sloppy tolerances (relatively speaking).* Any shade-tree mechanic can work on them successfully.

But a diesel like the FL120 is a somewhat different animal.* Water pumps, the belt, setting valve clearances, oil and coolant changes, and things like that are well within the ability of a mildly experienced auto guy.

But--- and this is just my advice, some may not agree--- don't even think about messing wit the injection pump or the injectors.* The in-line injection pump on the FL120 is amazingly complex piece of equipment with very precise settings and even more precise tolerances.* And unless you know what you are doing, it's the sort of thing that your screwing with it can result in "I adjusted that but now that doesn't work right."* It is a very "inter-related" device and everything has to be set exactly right in order for it all to work properly.

So in my opinon, unless one actually happens to be a qualified diesel mechanic, the injection pump and injectors should be left to the shop to deal with if they develop a problem.

Fortunately, if the engine is operated the way it was intended to be operated when they designed and built it, the injection pump is a very reliable unit outside of the plunger/bore wear I mentioned earlier which is just something that happens with this kind of pump.*

This was not the case when the engine was used for its original purpose which was to power heavy duty (by late '50s standards), over-the-road trucks.* The constantly changing rpm, the constantly varying load on the engine, and the higher rpm that was often needed to climb hills and maintain highway speeds were simply too much for the design, and failures were frequent according to the people I've talked to who had experience with this engine in the UK "back in the day."* The injection pump in particular was an Achilles' heel in this kind of service.* So in this regard, the engine was considered a failure and Ford quickly stopped using it as a truck engine.

But in the lower power, constant load, constant and conservative rpm range typical of industrial and agricultural engines, the Ford Dorset did just great.


-- Edited by Marin on Wednesday 29th of February 2012 01:09:43 PM