Lehman 225 engine mounted fuel filter replacement?

Headed down to the boat to change the filters. Any tips or tricks? This will be my first time.

Thanks
Steve

roll of paper towels & HD trash bag

SoWhat said:

roll of paper towels & HD trash bag

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And beer...got it

Just make absolutely sure you put the correct gasket in the proper place. These are not O rings but square cross section gaskets. If I remember correctly the gaskets may be different sizes, or not, just check carefully. Mine take about 75 pumps on the plunger to prime after changing. It really isn’t too bad just go slow and check that the gaskets are in the correct place and that the old gasket came out with the filter. I had one stick and didn’t notice it right away, it sure leaks air in then...

Greetings,
Mr. S. Hold off on the beer until done. I'm assuming CAV type filters, Also have close at hand: diapers, trash bucket, small containers to drain filter housing once you loosen but NOT remove the filter housing, more diapers, more paper towels.


Wear safety glasses and protective gloves. Make doubly sure you have the old o-rings removed (sometimes they hide) and you put the new o-rings in the proper locations (I think they may be different diameters).


I have found it advantageous to fill the new filters with a weeny funnel through the bleed hole after snugging everything up. It lessens the amount of priming you have to do with the fuel lift pump lever. An alternative is use an oil can (filled with diesel) to fill through the bleed hole.







Aw snap!!! Mr. C beat me by three minutes...Yup, not really o-rings but you'll see what we mean.

Thanks guys for the help. I didn’t get to the boat until 8 tonight. Decided to tackle this another day. Doesn’t look like a lot of fun, especially the starboard engine.

Maybe later this week I’ll give it another shot.

It is intimidating the first time, but go ahead and give it whirl. Let us know how it goes.

Comodave said:

It is intimidating the first time, but go ahead and give it whirl. Let us know how it goes.

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Will do. I’m anxious to do it. We had the starboard engine quit on us leaving us on one engine during our last trip. I’m hoping those filters are to blame.

Sounds like a plan, just be careful not to inkect another problem into the equation. Double check everything you do during the filter change. Good luck!

And don't be afraid to let the engines idle for 15 to 20 minutes after the filter change to make sure all the air is out of the lines and filters.

I have the same set of engines in a much smaller boat (36'). It takes me 10-15 min per engine to change 2 micron secondary filters. I use ziplock large freezer bags to put under and over the filter while unscrewing. I use 90 deg pick to extract the upper gasket. DO NOT forget to replace the tiny O ring gasket on the long bolt. And then priming. 20-25 pumps per filter. This is the easiest part. Nothing to be afraid about. You may have to bleed the high pressure pump using the side valve (NEVER touch the cylinder supply fuel lines)

Thanks for the advice everyone.

What exactly is the process of getting the old filters out and new ones in? I don’t want to take apart more than I have to.

I’ll be going down to the boat early next week.

Greetings,
Mr. S.
-Put on your safety glasses and gloves if you want to wear gloves.
-Get everything ready and very close to hand. Paper towels, diapers, TRASH PAIL, mirror, wrenches, small pick to take out top gasket, small container to drain filters, small container of clean diesel & small funnel (or oil can as I suggested above) to fill filters.
-Assume a comfortable position.
-Put diaper(s) under filters.
-Drain filters, one at a time, into small container via the white spigot on the bottom of each housing.
-Change diaper when you make a mess.
-Loosen nut on the top in the middle of the housing.
-Change diaper
-Remove filter and make SURE you remove the o-ring/gasket that will be in the top of the housing (use mirror and small pick).
-At the same time you remove the first filter element and gasket take note of the sizes of the gaskets and which one goes where.
-Change diaper.
-Wipe housing (top and bottom) with paper towel to remove any oil or dirt.
-Reassembly is the reverse of the above minus the multiple diaper changes making SURE the upper gasket is properly seated in the square groove in the housing. Some put a light coating of oil on the gaskets before installing but I've done without.
-Snug up the bolts and fill the filters with clean diesel.
-Bleed the rest of the system.
-Wipe everything down with paper towels and check for leaks.
-Close sea cock and try to start engine making sure that IF it starts you immediately open the sea cock.
-Check for leaks again.



Have that beer now while the engine runs for 15 or 20 minutes just to make sure you've purged all the air.

Firefly's procedure is spot on.

The part I usually forget is to bleed the system all the way to the injector pump. That becomes obvious when I start the engine and it runs for about 10 seconds then dies. It is mentioned above but be sure the 2 large gaskets don't get twisted when installing them and there is a small round gasket in the center of the housing.

I like the oil can idea. I always use a funnel and end up spilling more diesel to clean up.

Greetings,
Mr. NW. Aw snap! I forgot about the bolt gasket-Thanks. Hear that Mr. S?

RT Firefly said:

Greetings,
Mr. NW. Aw snap! I forgot about the bolt gasket-Thanks. Hear that Mr. S?

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Yes. That’s a perfect write up. Exactly what I was looking for. Thank you! I owe you one.

Make sure you know how to bleed the system after the change over.

Just did the port engine filters in about 30 minutes. Really not hard, just messy. Starboard engine isn’t going to be as much fun.

But now I can’t get this port engine started. I pumped that plunger about 60-80 times and had my electric priming pump going. Felt resistance with the plunger. Engine started and ran for About 10 seconds then dying. Now I just absolutely cannot get it to start. These pants are supposed to be self priming, so I don’t get it. I even cracked the return line off the pump and made sure fuel was coming out of it, which it was. This happened a couple months to me when I ran I tank dry. The port engine just took me hours and hours to finally get to start.

I’m gonna work on the starboard engine now and see how it goes

Change the filter. Then crack a vent on the top housing. Then pump lever. Stop when fuel starts coming out, then snug the vent. Pump a few more times, start engine. Both filters need to be vented of air as above.

With filter all closed up as you did it, pumping the lever only pushed air into the inj pump. If you open a vent, air comes out there and inj pump stays full of fuel.

Greetings,
Mr. S. See post #14. You must prime the injection pump as well.


"These pants are supposed to be self priming..." Ah, yes. Self priming pants. There's a fix for that...

Like Ski said, you have to crack the screw on the first filter when pumping. When solid fuel comes out close screw and open screw on second filter and repeat, then start the engine at fast idle. It may stumble a bit but should run. Good luck. You should start the priming process all over if you did it differently.

Ski in NC said:

Change the filter. Then crack a vent on the top housing. Then pump lever. Stop when fuel starts coming out, then snug the vent. Pump a few more times, start engine. Both filters need to be vented of air as above.

With filter all closed up as you did it, pumping the lever only pushed air into the inj pump. If you open a vent, air comes out there and inj pump stays full of fuel.

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Crap I forgot to crack that bleeder screws. Sure enough a ton of air came out. But still no start even after pumping the plunger another two dozen times.

Your symptom is exactly the same as mine when I forget to bleed (prime) the injector pump. On my pump you need to loosen the aft bleed screw and pump until you get clear diesel out of it. Not a mix of air and diesel. Then close that screw and open the forward bleed screw and pump again until diesel with no air comes out. Tighten the screw and give it a start.

Here is a picture of my pump and the locations of the bleed screws.

Try the bleeding process again. I would not mess with the injector pump until the correct bleeding has been done. On my 225s I have never had to bleed the pump, just the filters. Maybe you will have to bleed the pump since you got nore air into the system. Just try rebleeding the filters first.

Alight I’ll give it a shot tomorrow morning.

"But still no start even after pumping the plunger another two dozen times."

When hand pumping does fuel squirt out of the bleeding screw on the injection pump?

IF it does not , turning the engine a bit may allow the hand pump to be in a better position and move far enough to pump.

With the injection pump fully primed , you still might have to bleed the injectors.

FF said:

"But still no start even after pumping the plunger another two dozen times."

When hand pumping does fuel squirt out of the bleeding screw on the injection pump?

IF it does not , turning the engine a bit may allow the hand pump to be in a better position and move far enough to pump.

With the injection pump fully primed , you still might have to bleed the injectors.

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I believe you’re talking about the 135. The 225’s have a self bleeding pump.

Self bleeding or not, you don't want to work your lift pump with the starter. Work the lift pump by hand and verify both filters are solid with fuel (silly term, just means all fuel, no air) and the injection pump too.

Then try a start. If no go, crack injection lines at nuts up at cylinder head and crank til they spit. Note that priming pump will have no effect downstream at the injection lines, to pump fuel through that part of the inj pump it must be rotating.

Greetings,
Mr. S. "The 225’s have a self bleeding pump." They're SUPPOSED to be self bleeding. Maybe you've got a weak pump. You're unable to start your engine for a reason and the only reason appears to be lack of fuel.
As others have said. Start bleeding again from square one and buy yourself an oil can for the other engine (post #5) to aid in filling up the new filters from the bleed hole. I can see that outboard priming lever to be a tad awkward.