CAV Filter adapter

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That issue with the Simms pump only applies to the FL-120, not to the FL-135. The OP said he had a FL-135.

A much bigger problem than the final filtration is the 50 hour Simms pump oil change. A friend of mine who rebuilds Lehmans for a living says many owners neglect that maintenance and it has caused many Simms failures. Do yourself a favour, Simms owners, change the oil every 50 hours even if it is entirely a PITA.
 
Even then with 120s, the problem is with our dilution by fuel by a worn pump.

If you check the level of oil or can test for fuel in the oil (blotterl test), even American Diesel/Bomac said the 50 hrs is arbitrary. A number of posters have reported being told similar advice.

Yes, the simple thing is to just change it every 50.
 
The CAV filters are under pressure too and they are full of o-rings; I found the Racor 500 less fussy than the CAVs. My Racor mod was done in 2005 and its still going strong. There is no issue with water in the secondaries as it should have been dealt with in the primaries. Water getting past the primaries would screw up the CAVs too so that doesn't wash. At least with the clear bowl you can see any water, assuming you ever go down there.

I did not mount the Racor on the engine because there is no specs on the vibration-resistance of the Racor. I did not want the old clam-crusher to shake it apart. The little rattle-pump I installed in a valved loop next to the filter made it very easy to bleed.

The CAV filters have two O rings, a Racor turbine has 5. Still, if you mounted it off the engine that's good and both primary and secondary can be mounted before the pump, on the vacuum side, I've done this for folks who didn't want to deal with the on engine filter replacement, mostly spin ons, at sea.
 
What are the thoughts that the last bit of fuel reaching the injection pump should be through a filter ? Just in case.....

.....some even don't like rubber hoses between that last filter and the injection pump...
 
What are the thoughts that the last bit of fuel reaching the injection pump should be through a filter ? Just in case.....

.....some even don't like rubber hoses between that last filter and the injection pump...

Some rubber compounds will deteriorate over time, some not so much.
I would want that hose to be as short as possible...…..
 
My point about the Simms pump is that failures are much more prevalent with owner mis-use than the failure of the filtration. Racors are much easier to service and source filters for and make it possible to see the used elements. Seeing them and their condition can be used to judge the timing of filter changes and its very easy to install a pressure/flow gauge on the filter which, like a volt meter for battery condition :angel: is a simple gauge of filter replacement whereas the CAVs are hit-and-miss, change it because-it-feels-good or never change it because out-of-sight-out-of-mind.

How short does a fuel hose have to be? One foot or two? Is three feet too long? Four? The length of the fuel hose is immaterial and specious and I already suggested you have the lines made up.

I'm done with this discussion. I have provided an argument for the simplification of the fuel system. I had modded my Lehman by the filtration, venting, drains in the Simms, lift pump, rattle pump and injectors. All of this worked and has resulted in a Lehman that is still happily running since I did the mods in 2005. Some of this may make your life easier, some of you think I'm full of (boat word) which I might be: do whatever floats your boat.

I could be tricked into providing the name of the friend who rebuilds Lehmans. He blueprints them and rebuilds the injection pumps and he does it way cheaper than most rebuilders or block sales. He specializes in large commercial engines like tugs and coastal freighters and does the Lehmans in his shop. They run like a Rolex when he's done. He is near Vancouver.
 
As Steve D suggested, metal spin ons fill the bill. That said, I’ve changed many cartridge type filters over the years and quite frankly find changing out a Racor not that much easier.

Is there something so problematic with the poster’s OEM design that an alternative is required?
 
Is there something so problematic with the poster’s OEM design that an alternative is required?

I'm here..sitting in the background reading. Nothing so problematic that it absolutely requires a change. A couple of things combined cause me to see if there is something more convenient.

First is the location of the starboard CAV's. On the other side of the engine requiring me to crawl over and squeeze in a small space with not so comfortable seating. Would prefer not to have to do this. Irritating if I have to extricate myself to go get something I forgot or find I need. If I had spin-ons or Racors I could change them leaning over the engine from amidship. Much easier.

Second, I'm a relative newbie I don't have any experience with how long a secondary lasts on my boat. Uncomfortable with not seeing their condition. Primaries are 30 micron and on engine CAVs 4-7 or so. Would be nice to be able to visually check them. Could do that with Racors. If not then spin-on's which are more easily changed if in doubt. Which I am on my boat. All the time. About everything. :)

Had my starboard primary vacuum gauge start to increase. Small amount of debris in the bowl. How much got through to the CAV secondaries? You guys would know but I am clueless. I have to get back there, replace and then cut it open to see and learn.

I am rambling on about something that isn't that big a deal. Just curious about an easier setup is all. While I don't yet have the knowledge that experience brings like you folks I do have knowledge of and experience with ME. If something is a pain to do I will procrastinate and let it go. Anything I can do to make oil/fluid and filter changes easier on the boat is a good thing. To me they are too cheap to not change frequently, probably more frequently than really needed. Just trying to make it easy.
 
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What are the thoughts that the last bit of fuel reaching the injection pump should be through a filter ? Just in case.....

.....some even don't like rubber hoses between that last filter and the injection pump...

Oh I wouldn't ditch the CAV sandwich or spin on secondary filters, or metallic piping, as I said, best not to modify the on engine parts, I'm simply saying that having primary 30 or 10 micron Racor and secondary 2 micron Racor filters before the pump, and on engine filter, means the likelihood of the on engine filter needing replacement is far less likely. You could do it at your leisure rather than being forced to do so. As an aside, the primary filter should absolutely be equipped with a vacuum gauge, it's the only accurate means of knowing when it's time to change the filter. More on the vacuum gauge here https://www.proboat.com/2012/04/the-vacuum-gauge-tool/
 
For Ford Lehman Owners

I just spoke to Brian Smith, who says the adapter for the CAV-to-spin-on replacements likely won’t work for most Ford-Lehman engines because the heat exchanger directly below the filter elements is in the way. So they’re a no-go for my SP135s. (The exception is the FL120, where the heat exchanger isn’t in the way.)

If somebody has successfully installed a spin-on adapter on a 135, please post.

I explained that I’d like to move to an on-engine filter with a smaller than 10 micron rating, if possible. Brian says the FLs spec a 2-10 micron CAV filter and that the OEM Delphi 296 elements have denser filter media and are below 10 microns. (I’ve seen them rated at 5 to 7 microns; no idea what the efficiency is supposed to be.)

So to keep things “simple,” I’ll be using a Fleetguard 20 micron “mud” filter on the fuel transfer system, pumping fuel to the day tank. Next, the primary filters will be 10 micron (either the existing Racors or Fleetguard upgrades) and the on-engine CAVs will be the Delphis at 5-7 microns.

This should provide the graduated filtering that Tony Athens recommends.

Additionally, my fuel transfer system (I’m not calling it a polishing system) draws from the very bottom of the saddle tanks. So whenever I shift fuel to the day tank, I should get any water and crud that might be lurking out. Anyway, that’s the plan.
 
I just spoke to Brian Smith, who says the adapter for the CAV-to-spin-on replacements likely won’t work for most Ford-Lehman engines because the heat exchanger directly below the filter elements is in the way. So they’re a no-go for my SP135s. (The exception is the FL120, where the heat exchanger isn’t in the way.)

If somebody has successfully installed a spin-on adapter on a 135, please post.

Here is a pic of my port FL 135. Yes the HE is directly below the CAV's. I have no idea how long the replacement filters would be or if they would interfere. I'm willing to bet that Brian knows for sure but sure looks like a good bit of space.
 

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Here is a pic of my port FL 135. Yes the HE is directly below the CAV's. I have no idea how long the replacement filters would be or if they would interfere. I'm willing to bet that Brian knows for sure.

This is silly. Most people with FL135's, myself included have the spin on adapters with no fitment problem. In fact there's probably enough space to stack two filters in there.

Ken
 

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Ken,

Could you measure down from the original bracket on the engine to the bottom of the new spin on fuel filter and let me know how long it is? I would like to convert my SP 225s to spin on filters but don’t know if they will fit or not. Also what is the part number on the filters you are using?
 
This is silly. Most people with FL135's, myself included have the spin on adapters with no fitment problem. In fact there's probably enough space to stack two filters in there.

Ken

Sorry if my post proved wrong. I was passing along what I was told by a normally extremely reliable source. I’m not near my boat or I’d have measured before posting. Nice to see that some sort of spin-on fits and thanks for the pix.
 
Sorry if my post proved wrong. I was passing along what I was told by a normally extremely reliable source. I’m not near my boat or I’d have measured before posting. Nice to see that some sort of spin-on fits and thanks for the pix.

I will try to get to my boat this evening, time to go give her a hug, and will measure the space on my 135's and let you know.

RTF mentioned checking out the filter specs/ratings. Which filters that fit the adapter fall into the 2-10 micron category?

I'm going to touch on something that is fairly blasphemous around here but over the last 18 months I have found that the extremely reliable source mentioned to be somewhat... off base at times. Different/opposite answers on different days, flat out incorrect info..... I know, blasphemous.
 
Not at all, I have posted the same with no giant backlash.

No one source is perfect....hashing out the inputs from "experts" and weighing the source here on TF hopefully gives us all the best solution for each of us.

Just like talking to 2 different people at any company may get you 2 different answers.... Sometimes one person may give the same "answer" but toss in their dissenting opinion. :)

Also be suspect of posters who have owned and run EXACTLY one type of boat or system being talked about and swear that is the best way or that it works great. Easy to figure out where that one goes. Nothing wrong with that input, but it does need perspective.

Like when people here say it may not be the "proper" fix, but they did it temporarily and it's worked great for thousands of engine hours.... :) That one can be looked at 2 ways if you find the explanation plausible.
 
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Throw the filters away and remote-mount a Racor. Commonality, ease of maintenance, all the good things.

How long is your fuel line from the remote mounted Racor to the engine? I believe you mentioned having the lines made up for this application?
 
Not at all, I have posted the same with no giant backlash.

No one source is perfect....hashing out the inputs from "experts" and weighing the source here on TF hopefully gives us all the best solution for each of us.

Just like talking to 2 different people at any company may get you 2 different answers.... Sometimes one person may give the same "answer" but toss in their dissenting opinion. :)

Also be suspect of posters who have owned and run EXACTLY one type of boat or system being talked about and swear that is the best way or that it works great. Easy to figure out where that one goes. Nothing wrong with that input, but it does need perspective.

Like when people here say it may not be the "proper" fix, but they did it temporarily and it's worked great for thousands of engine hours.... :) That one can be looked at 2 ways if you find the explanation plausible.

Thanks PS. I like talking about these things, learning from others during the discussion. Somehow I always get back to the fact that the boat knows more than I do. Whatever my idea or upgrade, the original setup is something that was designed by the builder that the boat has used for 31 years and 4,300 hours and has been perfectly fine. And now here comes Mr. Newbie who wants to change it? I am pretty cautious (code word for scared to death) in the engine room, maybe overly so. There is a fine line between a real upgrade and pi$$ing on it to make it mine so to speak. That being said, the number of people who seem to have done this particular upgrade tells me it's a worthy and reasonable endeavor.
 
These are on a 135

Sorry only pictures that I have. This is a 135. Purchased this way.
 

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Thanks Easting. How do you fill them with fuel when you install? Pour through the top after or fill them up before spin on?
 
Thanks Easting. How do you fill them with fuel when you install? Pour through the top after or fill them up before spin on?

Haven’t changed them yet. :) Boat purchased in August. Will do in the spring. It does not have any type of auxiliary pump to prime so not sure what the best option will be.
 
Thanks PS. I like talking about these things, learning from others during the discussion. Somehow I always get back to the fact that the boat knows more than I do. Whatever my idea or upgrade, the original setup is something that was designed by the builder that the boat has used for 31 years and 4,300 hours and has been perfectly fine. And now here comes Mr. Newbie who wants to change it? I am pretty cautious (code word for scared to death) in the engine room, maybe overly so. There is a fine line between a real upgrade and pi$$ing on it to make it mine so to speak. That being said, the number of people who seem to have done this particular upgrade tells me it's a worthy and reasonable endeavor.

Some boats and engines can use the help though, especially older tech ones.

This was my solution to my crumbling CAVs.

Even sold them to pay for a lot of the new filter.
 

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Ken,

Could you measure down from the original bracket on the engine to the bottom of the new spin on fuel filter and let me know how long it is? I would like to convert my SP 225s to spin on filters but don’t know if they will fit or not. Also what is the part number on the filters you are using?


I probably won't be back to the boat for a couple of weeks, but I'll try to get you the measurements then. There's really quite a bit of space.



The filter is a WIx 33361 which has a nominal 6 micron rating.


As far as prefilling the filters goes I've read its better if you can fill them with a pump after install due to the fact that pouring fuel into the filter means you get a slug of totally unfiltered fuel to the injector pump. This sounds logical to me, but considering the thousands of gallons of fuel that go through the pump, one small quantity of unfiltered (as long as its clean fuel) shouldn't really be a problem. My boat happened to come with electric pumps for priming which work very well.



Ken
 
Blasphemous, I’ll tiptoe in—-

How does one know the micron rating or beta ratio of your last chance fuel filter if you stray from OEM? The danger of a thread like this is that because something can be done doesn’t mean it should be done.

Personally, if concerned about changing the CAVs annually, I’d add a good SB marine fleet guard setup in advance of the last chance. Then the last chance will move out to several year cycle. Surely one can take the time to change the last chance every few years with an OEM filter and not screw up your injection system. :hide:
 
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Greetings,
I have, in the past, very seriously considered a spin on(s) as a CAV replacement on our 120's due to the PIA factor of changing the CAV's. Fortunately or unfortunately, the last time I did do a filter change it went swimmingly. No problem what-so-ever. So now, I'm torn. Replace with spin-on adapters or leave as is...


200w.gif



Edit: No clearance problems on the 120.
 
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I had once considered spin on adapters for the dual CAV filters on my Perkins T6.3544 engine, but realized as you did I didn't have enough clearance under the filters as the adapters add an inch or two in height. I'll stay with what I have.
 
Here's another rock to drop in your pond, nothing to do with fuel, but why are you Lehman owners leaving your oil filters mounted upside down so that they drain when you shut down? I'll bet dollars to doughnuts those filters are partially or totally empty when you start and it takes a few seconds to get oil pressure after a cold start? I'll also bet that removing that filter makes a huge mess when its time to change it out? You are relying on a check valve mounted on the filter, if you are lucky it is in the filter mount body but don't hold your breath; many filters do not even have that simple thing. Make your bearings happy and keep your engine room cleaner and mount the filter "upside down" like a mug of coffee.

Why not invert it? There appears to be plenty of room in that photo. That's another mod I made, the oil pressure was nearly instant on a cold start with inverting and all you need to do is use a ziplock bag over it to change it out. Remember to fill it before installation. All the Cummins I am familiar with mount the oil filter that way.
 
Greetings,
Mr. X. I never noticed that on the 135's. I thought ours were bad being sideways (Only 1/2 the mess I suppose). Yup, one of these days, longer oil lines and like a coffee mug.
 
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