Should I add bypass filter?

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Originally Posted By: Gary Allan
Fuel usage is a good indicator of oil fatigue. Being EFI is a great plus. Nice engine.

How well do you maintain coolant temp? Do you have an oil temp gauge?
I would rather have a carb.Carbs wearout efi can fail.
 
I'm trying to keep the OP's use in mind here.

He has a fishing boat. It's not a ski boat, nor a drag boat, nor an off-shore racer here.

His operating patterns are likely this: start up and idle while preparing for launch, idle out of zone, full throttle to get up on plane, back off to (around) 2/3 throttle to cruise to a fishing spot, idle down to not scare the fish when getting close, then stop. Repeat as necessary. I aksed him in another post if he's doing a lot of trolling and the answer was "no", so excessive idling (fuel dilution) is not an issue.

With this in mind, he's likely to treat his motor no different than the engine in my wife's minivan. Start up and wait for the kids to get in and buckeled up, idle down the long drive to the county road, pull out and hammer it until up to 60 mph, drive to school for drop off, then "city traffic" to work.

Sound familiar? Yes, a boat uses more fuel per distance traveled, but the useage pattern is VERY similar.

This boat engine needs a 195 deg T-stat, and some HDEO multi-weight, with an oil-temp conditioning device (block water to oil heat exchanger?) to bring the oil up to temp and then hold it there as soon as possible. Then multiple UOAs.

I'm beginning to understand why conventional vehicle engines that are converted to marine use are subject to high wear. They probably operate too cold, and use oil that's too thick. The outside ambient air temp has very little effect on the motor. Typically, a boat motor such as this uses the lake/river water as a direct cooling medium; there is no secondary cooling system. On a houseboat, with a diesel gen-set, the lake water is drawn in to cool a self contained system that cools the engine; a water-to-water system. But most boat motors, be they vehicle based engines or marine-specific two-stroke engines, use direct water exchange. Running a 351 Windsor engine at 165 deg F with a straight 40 weight is going to definitely produce some high wear metals.


It seems apparent to me that this motor is a glorified truck engine in both origin and useage pattern, and should be treated as such.
 
You guys have been working without me. I picked up the bt1305 filter head, so I am going to add the bypass oil filtration.

The engine is fresh water cooled using a water to water heat exchanger. It is what is called a 1/2 system meaning that the exhaust mamifolds and risers are still salt water cooled. The stock thermostat is 160 degrees. If this engine were raw water cooled ( no heat exchanger, salt water running through block)the stock thermostat would be 143 degrees. I believe the lower than normal temps are to prevent salt and mineral build up in the cooling passages. I have a call into the manufacturer to see what they say. I'll also ask about the straight weight oil recomendation.

By the way I will be lucky to get 3 MPG and it is not a big boat. 20' Shamrock with a full keel which adds drag.
 
"His operating patterns are likely this: start up and idle while preparing for launch, idle out of zone, full throttle to get up on plane, back off to (around) 2/3 throttle to cruise to a fishing spot, idle down to not scare the fish when getting close, then stop. Repeat as necessary. I aksed him in another post if he's doing a lot of trolling and the answer was "no", so excessive idling (fuel dilution) is not an issue."


Just about right. Boat planes easily at 1/2 throttle, no need for WOT. Plenty of power, maybe too much.
 
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I believe the lower than normal temps are to prevent salt and mineral build up in the cooling passages.


Scale build up surely is a consideration ..but in an exchanged situation... one would reason that they could surely trump any operating temp (engine loop) with massive over-flow capability to make the raw coolant side remain in a favorable range to inhibit particle precipitation. Tube velocity can be manipulated a few ways ..but you can surely be limited due to dimensional confines and I'm sure that hp requirements to provide cooling are in the mix too.
 
Stock thermostat at 160 deg, and 3 mpg? YIKES!

It's interesting that you have a split cooling system. I've heard of that, but I thought it was rare overall. My word, 143 deg F on a full exchange system? That's just plain cold for a engine that was never designed for marine service.

Perhaps tell me more about the origin of the motor itself. Is it a brand new block and engine, or is it a re-man? Further, was it built by a marine-specific builder, or some shop that does all differnt kinds of engines? Just curious; don't know that would matter one way or another, but wanting to know.

When you add the BP system, if at all possible, do yourself (and us) a favor: install an oil sample port within easy reach. At this point I must admit the application of this engine must be far outside it's original design intent. Perhaps 25 hour OCI's are warranted, at least until UOA's say otherwise. The upside is that your usage pattern isn't really "heavy"; no extreme idling or full throttle application for any length of time. If your plan is to run around 100 hours for the season, then 4 UOA's would be a great start for a knowledge base. If you'll post the info, (perhaps send me a PM when you do post), I'll offer to track your data in my UOA studies, so that I can give you statistical analysis along the way.
 
Gary, Your right, the raw water loop runs cooler than the engine loop. I do not know the differential though. I did take a temp on the stainless thin wall exhaust tube and if I remember correctly it was in the range of 120F at cruise.

Dnewton, The half cooling system is the more common system. The exchanger may have to be twice the size to cool the exhaust manifolds, and most manifold are not designed to be in the closed loop. The 143 F thermostat was stock in the non exchanged engine( sea water running through the block).

The engine is new with 25 hrs, not a rebuild. It is a PCM/ Crusader marine conversion. PCM has used this block for many years both carb and EFI mainly targeting the Ski boat market. Crusader is their true marine line and I believe they offer a full closed loop cooling system.

Would the oil sample port just be a T and a valve or plug down stream of the bypass filter?

PCM has not returned my call yet.
 
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Gary, Your right, the raw water loop runs cooler than the engine loop. I do not know the differential though. I did take a temp on the stainless thin wall exhaust tube and if I remember correctly it was in the range of 120F at cruise.


Just out of my ignorance and curiosity, how is the secondary (raw) loop flow driven? Belt? Direct coupling?

I'm just figuring how I couldn't manage to leave this thing alone in the OEM state with such low an op temp. I'm a prisoner of my paradigms
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As far as the oil sample port goes, you can get "fancy" and get a nice design-specific valve like a Fumotor valve, or you can just get a plain old WOG valve at the hardware store. Either way, you'll have to come up with a few small pipe fittings to get "tee-d" from the filter base to the valve.

Gary could probably suggest the "best" approach. I'd be able to do it in my garage with parts from all my left over projects, in 10 minutes or less, and it would work perfectly, but it'd also likely resembly a Frankenstien project (a little of this, a little of that ...).

The question many would debate, but I don't really think it worthy of all that much argument, is to sample "pre" or "post" filter. My gut feeling is either "post" FF filter, or "pre" BP filter; this represents the bulk of the oil that the engine experiences. But, what would matter most to the UOA is the consistiency of the approach. I, like most BITOGERS, am willing to live vicariously through others. But as I've stated before, if you're going to do UOAs and you want results that mean something, you must apply a steady series of inputs to get quality from your outputs. Choose one brand/grade of oil for the entire season. I'm not saying that you should not change oil, I'm saying use the same brand/grade oil for each OCI. Specifically, if you can pony up the money, buy ALL the oil for the whole season at once, to assure it's from the same lot of manufacture. Then use the same principle with the filters. Take your samples after engine is (as much as this boat motor can muster) warmed up. Try to opertate it with consistent patterns. Post up the UOA's and we'll delight in the progress.

The downside to this initial project is that your motor is new, and no matter what you do, it's going to shed some extra metals just due to the break-in effect. And as cold as these apparently seem to run, there's no telling just how good/bad those first reports might be. They could be shocking to most of us, but "normal" for a converted marine engine; we won't know until you post!
 
Gary, The raw water pump is a belt driven rubber impeller pump. Some manufacturers direct drive the pump off of the crank.

PCM called back. The 160 thermostat is a trade off between power/economy and scale buildup. The owners manual I received with the engine in 2007, was printed in 2000. It recomended straight weight oil. They now say multi viscosity is OK, Synthetic OK but continue 50 hr OCI. Thanks PCM for upgrading the manual.

The new recomendition is 15W40-GF-4/SM

What oil should I use? The Amsoil Marine is $$$ and hard to get.
Any full flow filter recomendations?
 
15w/40 are HDEOS like Delo 400 ,Rotella Delvac 1300 ,they cost around $10.00 a gallon at Walmart and a few dollars more at auto parts stores . They are great oils.
 
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Gary, The raw water pump is a belt driven rubber impeller pump. //The 160 thermostat is a trade off between power/economy and scale buildup.


Then I'd be surely tempted into manipulating the sheave/pulley size to allow a 195F thermostat and still maintain the lower raw water working temp. There should be no scale on the engine loop side. Much you don't know, however. If it's a turbulent flow, then I'd say it should work out to an equivalency of effective temp. If it's a laminar flow, then the boundary shears will be seeing the higher temp.

What's the normal fatigue/replacement rate for your exchanger? One would reason the exchanger replacement is far cheaper than engine overhaul/refit/replacement. If this engine could be pushed into a passenger car/truck level of longevity, then the (potential) trade off in exchanger replacement would be worth it. You would be way on the + side of things ..even if the moisture element of the environment meant continuing with short OCIs.

Is this a speed density EFI or an MAF (mass airflow) setup?

With your hours of service, assuming you intend to replace the filter with every oil change, any decent full flow will do the job. Your attacking agents are probably a result of enriched fuel charge/fuel dilution due to the overcooled state. I can't really see a better filter doing much here. If you want to leave it on for 100 hours or more, then it will work out in some small corner of some economic view in this very big picture of $$$ ..if you see what I mean
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Originally Posted By: Steve S
The 160*f thermostat is fine.


Well, Steve ..is that all you're going to give us? I mean ..there's plenty of references that temps below 180F increase ring wear substantially. Given that this has a 50 hour OCI and uses about 6-8X the fuel that a passenger/truck application would in comparative mileage/hours ..and that the refresh rate for the engine is probably in some proportion to this rate of consumption/depletion of petroleum passing through it ...can you give us a little more here?
 
Gary, The EFI system is a stock setup used on the Ford GT40 engines. The copper exchanger costs around $400 and has a fairly long life span. I believe you can also boil them clean or use a mild acid to remove scale. The cast iron exhaust manifolds usually corrode up over time and restrict the raw water flow and raise the opperating temp. The manifolds should be inspected after 4-5 years and replaced if necessary.If the manifolds develope leaks, which they do, it allows raw water to enter the exhaust and either rusting the valve stems or hydro-locking the engine. The raw water pump seems to have sufficient water flow. After it leaves the exchanger it cools the exhaust manifolds and they run about 120 F.

If running a hotter engine would give better efficiency and longevity I would be all for it. Are there any studies out there?
 
Originally Posted By: Gary Allan
Originally Posted By: Steve S
The 160*f thermostat is fine.


Well, Steve ..is that all you're going to give us? I mean ..there's plenty of references that temps below 180F increase ring wear substantially. Given that this has a 50 hour OCI and uses about 6-8X the fuel that a passenger/truck application would in comparative mileage/hours ..and that the refresh rate for the engine is probably in some proportion to this rate of consumption/depletion of petroleum passing through it ...can you give us a little more here?
Yes that is it a 160*f thermostat is the choice for the engine and its intended use. Why do the mfgs use this temp? Crusader is the nicer of marine setups.I would guess they do not have any idea on what works best. Who pays to warranty the engine? Marine use and auto use can't be considered the same.
 
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The EFI system is a stock setup used on the Ford GT40 engines.
It seems to be a speed-density system by most web references..but you can tell a MAF system by the MAF sensor above the throttle body. These were the preferred systems for hopping up on the 89-93 Mustangs. The system could handle up to 7 liters with other than stock cams and remain well mannered.



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The raw water pump seems to have sufficient water flow. After it leaves the exchanger it cools the exhaust manifolds and they run about 120 F.


I'm sure that it has. My only thought was that the OEM may have 120F as a target temp for max longevity. If that was a mandated or preferred temp, pulley manipulation would be one option to (perhaps) maintain it.

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Are there any studies out there?


Well, yes ..but in marine usage they appear to be limited mostly to diesels. I can't seem to find the SAE (like) paper that shows the substantial upramp in wear below the 180F threshold. I'll keep looking for the study that I'm thinking of. There are others, but the sources, although sharing this view, aren't the most authoritative/accredited. Not bad sources, just not backing the assertions with study numbers and such.

..and Steve:

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Yes that is it a 160*f thermostat is the choice for the engine and its intended use. Why do the mfgs use this temp? Crusader is the nicer of marine setups.I would guess they do not have any idea on what works best. Who pays to warranty the engine? Marine use and auto use can't be considered the same.


Well, I tend to agree with you in that they should know best ..and probably do. But we have no bearing on what they are trying to prevent or facilitate with the use of cooler operating temps and we can easily see that whatever that reason is, it tends to coincide with a much shorter life for the engine. Outside of manageable environmental influences, the installation should be transparent with a like load curve on a dyno test bench. Properly setup, it should last just as long as a non-marine installation. If this is not possible .. I'd surely like to know why ..or rather ...why not(?). We see all kinds of compensatory measures taken by the OEM's to account for consumer ignorance/convenience. They compensate for habits in typical usage. I imagine that Crusader works under the same paradigm that they can't educate every end user and that their clientèle are more into performance than they are longevity ..and probably don't know the difference ..or do not care. The ownership does tend to imply a more distinctive level of ownership ..much like the personal aircraft market.

..but..I'd surely like a peek into the rationale~ behind it.
 
As Waterskier has stated, seems like the OEM is a little lax on the info sharing. A 2000 manual for a 2007 engine? That's a bit outdated, to say the least. Now they state a multi-weight is acceptable! That was my prediction from the start; 15w-40 HDEO, or possibly a 10w-30 HDEO as cold as it runs.

I still say raising the block temp will produce better UOA's. Since this is a split cooling system, raising the block temp should be no problem, right?

I fully agree with Gary on the topic of (what I'll call) "selective longevity". I'd rather replace some exhaust manifolds and a water pump at 5 years, than the whole engine at 7 years. It's cost effective to have some sacraficial components, to save the life of the engine as a whole.

UOA's are going to be the key to long engine life. I don't believe this engine manufacturer can tell you any more than a UOA. While I do agree fully that a UOA is an INdirect statement of engine health, it still points to a general direction of aptitude. A particle count would help as well, but that starts to get expensive to say the least. Blackstone has marine UOA averages in their database.
 
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