Changing the Fuel Filter on a Yanmar 4JH2-TE

[DennisL]

I have now changed the fuel filter on my engine twice. Both times I filled the filter with diesel and pumped the little handle on the fuel pump until no more bubbles appear at the bleed screw/bolt. Both times the engine started and died.

It hasn't been that difficult to open the nuts on the injectors and crank the engine to get it started, but by that time my back and chest hurt so much from all the bending and contorting I'd just as soon be drinking beer.

So my question is this: how do you avoid bleeding the engine when changing the fuel filter?

 

[Sailgunner]

On my 4JH2E I never have to bleed it. Turn fuel lines off at primary filter. Fill new filters with fuel. Open fuel line valves and start engine.

 

[sailorskier]

I installed a dual racor system recently and added a priming bulb before the filters. I can change either filter primary or secondary an pump out any air.

 

[Rick486]

On my 4JH2E I never have to bleed it. Turn fuel lines off at primary filter. Fill new filters with fuel. Open fuel line valves and start engine.

Same here except I shut fuel off at tank 4jh4e. Starts right away with no bleeding. The Yanmars are self-priming.

 

[DennisL]

I appreciate the replies.

So Rick, can you explain a bit more about self priming. The manual I read said to stop cranking the engine when it dies. Is that incorrect? Do you just keep cranking until the engine starts?

I also have dual Racors, mounted next to the fuel tank, and a small 12 volt pump before them. It fills the bowls after replacing the Racor filters, but doesn't seem to have enough juice to push fuel from near the tank to the engine. I've also closed the valves at the Racors before changing the engine filter.

I'm clearly doing something different than what you guys do, but I'm not sure what.

 

[Rick486]

I appreciate the replies.

So Rick, can you explain a bit more about self priming. The manual I read said to stop cranking the engine when it dies. Is that incorrect? Do you just keep cranking until the engine starts?

I also have dual Racors, mounted next to the fuel tank, and a small 12 volt pump before them. It fills the bowls after replacing the Racor filters, but doesn't seem to have enough juice to push fuel from near the tank to the engine. I've also closed the valves at the Racors before changing the engine filter.

I'm clearly doing something different than what you guys do, but I'm not sure what.

So where does the air go from the 2 racors when the pump fills the filters? Maybe all that air is ending up downstream at the injection pump. That will definitely stop the engine.

My experience with Racors is to fill the filter with fresh fuel before installing the filter, as per the instructions on the filter.

My procedure for changing filters on my 4jh4e goes like this:
1. On engine filter. I do this one first.
-Shut off fuel cock on tank.
-Remove filter into a freezer bag.
-fill new filter with fresh fuel as close to the top as I can get it.
-rub fuel on filter gasket
-screw on filter and tighten per instructions
-open fuel cock on tank
-start engine and run for 5 minutes or so to ensure any trapped air is cleared.
I have been doing this for 9 years with this engine and it starts after the filter replacement instantly, as it always does. Never had a problem and never bled anything.
2. Racor primary filter
-shut of fuel cock on tank
-unscrew Racor filter into freezer bag and remove bowl on bottom.
-place bowl on new filter and fill with fresh fuel as close to the top as possible.
-rub fuel on gasket as per instructions
-install and tighten as per instructions.
-open fuel cock on tank and start engine. Run for five minutes or so. Same result as above. Engine starts immediately and runs as always.

I should mention the elevation of the top of the fuel tank is maybe 6 inches below the on engine filter and maybe 18 inches below the Racor filter.

I don't know how to answer your question on cranking the engine. I have no experience with the engine not starting.

After thinking this over your problem may be with the entrapped air in your racors.
-

 

[Charles Erwin]

Maybe this will help

Dual Racors are plumbed to allow one to be used and the other isolated in reserve. Each filter has two valves. If one filter becomes fouled you open both valves on the reserve, close both valves on the fouled filter. The fouled filter is now isolated so you can change the filter element and do it while the motor is running.

A typical motor mounted fuel pump will provide enough pressure to fill any racor filter and the guard filter - the one the manufacturer puts on the motor. So will an electric if it is between the tank and the racors.

A nearly fool proof method is: Make sure both valves at one of the the racors are open. Fill the racor(s) completely - you will need to slack the tee handle for air to escape on your 500's - then tighten the lid. Both need to be full of fuel - no air allowed. Next crack open the bleed screw at the guard filter, allow the air to escape, then tighten that screw. The bleed screw on the top of the guard filter is at the highest point of them all. It is very rare that you will need to open any other fittings. The last of the air will be at the top of the guard filter - that is why the bleed screw is located there and that is also why this bleed screw gets done last.

This method assumes the racor height is lower than the guard filter if not then you need to go back and verify the racor canisters have no air.

Charles

Edit: Your dual racor setup may have only one valve but it does the same thing as the two valve setup.

 

[DennisL]

Thanks a lot for the reply Rick. The back and forth is how I think things get clarified.

I know air is getting in there, just not sure how. I don't think it's through the Racors. I've done the reverse of what you do and change the Racors first. There are isolation valves back there so I can close one or both, and that's what I've done as opposed to closing the valve on the tank. I've changed just the Racors and not the engine filter before and not had to bleed, so I'm pretty sure the problem lies with the engine filter.

I had the engine fuel filter full of fuel when I screwed it on, and fuel ran down the sides, so I think things were good there. I opened the bleed screw which maybe is where I'm going wrong, but my Seloc Yanmar manual says you have to bleed when you change the fuel filter. Sounds as though you don't mess with the bleed screw?

 

[Rick486]

Thanks a lot for the reply Rick. The back and forth is how I think things get clarified.

I know air is getting in there, just not sure how. I don't think it's through the Racors. I've done the reverse of what you do and change the Racors first. There are isolation valves back there so I can close one or both, and that's what I've done as opposed to closing the valve on the tank. I've changed just the Racors and not the engine filter before and not had to bleed, so I'm pretty sure the problem lies with the engine filter.

I had the engine fuel filter full of fuel when I screwed it on, and fuel ran down the sides, so I think things were good there. I opened the bleed screw which maybe is where I'm going wrong, but my Seloc Yanmar manual says you have to bleed when you change the fuel filter. Sounds as though you don't mess with the bleed screw?

Nope. Never need to. Engine starts right up.

 

[DennisL]

Well that explains what I'm doing different. Hopefully I can remember not to open that screw next time I change the filter. Naw, I'll forget. I'll write on the box the filter comes in, "Don't Open Bleed Screw." Thanks.

 

[Terry Cox]

Hi Dennis, not sure why you have had to change your fuel filter twice now. Here is what I have experienced with our 1991 4JH2-TE. The engine had 647 hours on it when we purchased Belle-Vie in 2002. It now has 1932. The engine fuel feed has a primary Racor 10 micron cartridge filter between the tank and the engine. I have replaced it twice since taking ownership. The engine has a Dana brand ten micron canister filter that I have never changed. I do, however, have a spare NAPA ten micron canister filter.

I periodically check the Racor for water contamination, but it always comes out absent water. When I have replaced the Racor I top off the canister container with fuel and the engine starts right up and runs without a sputter. The first time I replaced the Racor the membrane was black from stuff. Doing its job, I guess.

 

[DennisL]

Hi Terry,
In my book, you're the old man in the sea with regards to Hunter 42's so I appreciate your input.
On our shake down cruise, a 40 mile trip from San Diego to Oceanside, the engine died. I went down thinking we were out of fuel and opened the access port on the fuel tank. It looked like pieces of toilet paper floating with a bunch of black stuff washing back and forth on the bottom. I changed the Racor and made it the final few miles to Oceanside, and even back to San Diego. But I knew the guy who "polished" the fuel hadn't really polished the fuel.
So upon our return, I sucked out all the dirty fuel, paid the fuel dock $1/gallon to take back the dirty fuel, and scrubbed the welds, bottoms, sides, tops and baffles of the tank. This was about 20 hours after originally replacing the engine fuel filter.
So we're about to do a trip to Catalina with my son and his girlfriend before he deploys and I wanted to make extra certain there were no problems. (He's a Marine so it's more for my wife than him.) So while the engine fuel filter only had about 55 hours, I decided safe is better than sorry and changed it. I'm glad I did because it had some of the granular black stuff I scrubbed out of the tank.
In any case, I feel as though I have the filter change/bleed problem solved by not opening the bleed screw. But you mentioned using 10 micron Racors and 10 micron engine filters. I bought the Yanmar filter and don't really know what micron size it is, but the mechanic told me to use 30 micron filters in the Racors because Yanmar fuel systems are so high pressure, returning a lot of fuel. I have 30's in there now based on his recommendation. I guess time will tell whether this is problematic.

 

[Terry Cox]

Thanks Dennis for the kind words. It sounds like you have the fix on your fuel situation. Nicely done.

Unsure about the mechanic's rationale for 30 micron. And I've never had the need to polish our fuel. I have checked the inside of our tank with a flash light and was unable to detect anything but nice clean red diesel. I do use a biocide treatment to help keep green stuff from forming.

Otherwise, the 4J starts and purrs like a kitten regardless of weather, temperature or sea state conditions. At this point I see no reason to change from what we have. Also, our boat came with an Onan 8kw Genset that draws fuel from the same tank using a dedicated ten micron Racor. The only difference was that the original Onan cartridge fuel filter was two micron. Two years ago, when the Onan stopped running due to a clogged original 1991 filter I replaced it with a six micron NAPA canister. When we purchased Belle-Vie in 2002, the Onan had 280 hours and now has 456. When I filled the new canister with fuel and installed it, the engine (three cylinder Kubota) fired right up.

I've talked with a number of industrial diesel mechanics and they tell me that ten micron is sufficient protection.

P.S. Would you please, for me, thank your son for his service to our country?

 

[DennisL]

We had an Ericson 39 when we were in Silverdale docked at Brownsville, behind Bainbridge Island. I spent much of each year away, but when we went to the boat, she fired right up. Maybe it was blind luck. Maybe I should have never looked in my Hunter 42's fuel tank. I don't know. But... the 42 did have terrible fuel, and I do now religiously use biocide.
I did use 10 micron filters before on the 42. I've even tried 2 micron, 10 and 30. I guess if you keep the fuel as clean as possible you're good with any of them.

I've read all the stuff about condensation and growth forming in the tanks. With the temperature variations in your part of the world I would think that would enhance it, but I didn't seem to have problems and neither do you.

I'm pretty sure the PO sold the boat because of fuel problems. He had 8 or 10 spare Racor filters by the fuel tank, and someone signed his name and the date stating the fuel had been polished. But if you don't get the stuff on the bottom and walls of the tank, it's useless. Anyway, I think and hope we're past all that.

We don't have a generator on our 42. But as long as the inverter can make my wife's coffee in the morning, everyone is happy. So far so good.

I will pass on your gratitude to my son. Thank you for recognizing him.

 

[Terry Cox]

You are most welcome, Dennis. Enlisted in the Navy and ended up on the aviation side with VF-114, the Aardvarks (Phantom F4H). Did two Kitty Hawk cruises, the second one we were the first to enter the beginning stages of the Vietnam War in late 63 early 64. Eery feeling observing planes returning to the ship shot up from shrapnel, etc. Then watching artillery on shore at night from a safe 26 miles off the coast of Vietnam.

 

[DennisL]

Thank you for your service Terry. That was a tough time. I'm probably a few years younger than you so it was different for me. I ended up a merchant marine. But my wife was Navy. Navy medicine. In fact they would invite me to their dining in's so they could have a "real" sailor. We had a lot of fun. Also had neighbors off the boomers. My daughter was born at Bremerton Naval Hospital. And what a GREAT place to sail. But the rain bothered my wife so we never went back. I'm sure there are a lot of Washingtonians grateful for that.