Fuel Separator

[jpaflag]

2002 Alfa see-ya with cat 3126E 330hp

Hello forum. It is nice to have a place where other owners can share their experiences.

I bought this coach over a year ago and had the fluids changed engine,tranny.

 

Recently I had the radiator flushed.  

Today after reading a maintenance schedule It said to drain the water from the bowl of the fuel separator. As I was draining I couldn't tell if there was water draining from the bowl so I tried to close the drain but it wouldn't close tightly and was still draining until I got a wrench to tighten it close.

Now it won't start   Tried to start it many times with no luck   Am I missing something simple to get the engine to start

Any suggestions anyone ever had this problem?  Where can I call for help?

Thanks in advanced

 

 

 

 

 

[wolfe10]

jpaflag,

Welcome to the FMCA Forum.

Do you have a Caterpillar secondary fuel filter?  Does it have a manual primer pump?  If so, use it to prime the fuel system.

[obedb]

Can you post a pic of the separator? The ones that I have used over the years on tractor trailers were Racors with  a removable lid and a secondary filter upstream. To prime the system it took about 50 strokes on the pump that Brett mentioned, and there was a bleeder nut that you had to open to force the air out before pumping. In my case you had to make sure that the separator was full of fuel before you start with the primer pump.When the bleeder quits blowing bubbles and fuel comes out close the bleeder nut. Of course the engines I used were 15 liters.  I don't know if the HEUI pump has a bleeder valve. Brett may know. 

[obedb]

Another thought. Make sure that the separator is full of clean fuel. Tighten it and then remove the secondary filter. If it is down , top it off with clean fuel by pouring it down the small holes until the filter is full. Replace it. By leaving the drain open on the separator, you no doubt have air in the system. The primer pump would be best idea but I don't have one on my 3126E. Hope you do.

[jleamont]

No need to bleed the HEUI pump, it will build it on its own (self priming pump) once there is sufficient oil in the system to do so, assuming everything is working properly.

Sounds like he is air bound on the fuel side (not the HEUI side), hopefully he has a hand pump primer option.

[obedb]

Making sure both filters are topped off will be the trick then. If it starts it will rough for a bit and then hopefully smooth out. Might have to fill the filters a second time if it runs and then shuts off. My series 60 had a manually operated check valve to prevent back flow when the filters were changed. If it was not closed when changing the filters  the engine would run for a short time and shutdown. Then out came the ether while I cranked it. After a time or two I was annoying when telling the guys at Speedco about the valve. When I made them my primary service point they got it. I know that you are not supposed to use ether on the small diesels because of the heater in the intake manifold, but had to on bigger engines from time to time.

[wolfe10]

With the Caterpillar manual primer pump, no need to open a bleed screw.  It primes through the engine, check valve and back the return line to the tank.  It will go from easy (air is compressible) to very hard in a couple of strokes (fuel pushing against the check valve is not compressible).  But it may take 50-75 strokes to get rid of the air.

Also, be aware that if the level of fuel in the tank is lower than the filter head, when you remove the filter, fuel will flow all the way back to the tank, leaving you with 25+ feet of AIR.  If this is the case, it may no prime with "normal methods". The solution if this is the case is to either loosen the bleed valve on the primary fuel filter or just loosen the filter element a little.  Use compressed air in the fuel tank fill-- just put your hand over the opening with the air nozzle between thumb and index finger.  All you need is 1-2 PSI-- enough to drive fuel through the line.  Of course the best long-term solution is a ball valve on the inlet side of the secondary fuel filter.  When changing fuel filters, just shut it off.  Also, makes a heck of a good theft proofing!

[jpaflag]

Thanks for the replies.

There is no secondary filter and no manual pump.

I've tried to start about 10 times and it seems to want to but I don't want to wear the battery out.

Ill keep trying.

[obedb]

Was not uncommon back in the day to observe a reefer tank ( refrigerated trailer ) with a metal air valve welded onto a metal cap for the fuel tank. They commonly ran out of fuel especially when the driver was running hard to the destination and was careless about stopping. Used that feature myself a time or two😎. It does work but the refrigeration unit on the front of the trailer still had a primer pump. They worked together. Tank pressure and primer pump. You gotta get fuel upstream of your separator and close enough to the HEUI pump to self prime. Did not know the HEUI did that. Thanks Joe. Please let us know how you make out?

[jleamont]

Obedb, the HEUI pump pumps oil, not fuel.

This explains how it operates.

http://www.dieselhub.com/tech/heui.html

[wolfe10]

1 hour ago, jleamont said:

Obedb, the HEUI pump pumps oil, not fuel.

This explains how it operates.

http://www.dieselhub.com/tech/heui.html

Yes and no.  The HEUI pump does use oil to substantially increase fuel pressure for injection.  But, it has to have diesel, not air, to allow the engine to start and run.

[obedb]

Joe/ Good article on the HEUI pump. The transfer or lift pump that supplies the HEUI pump with diesel is mechanically driven I guess.  How long would the engine have to be turned over to pull fuel from a front mounted tank? I have always observed the thirty second crank rule on hard to start situations with a rest period of at least 2 minutes or more to not burn the starter up. If there is no check valve between the OP's Filter/Separator some fuel could flow back into the tank?

You put an electric pump next to your tank, and that would be a real benefit in a situation like this!

 

[jleamont]

ObedB, that's an incredible distance to cover for a mechanical lift pump mounted so far away from the fuel source. I'm not sure it could handle that task at the RPM its spinning with the starter. I can speak from experience (you also) on a truck its a tough task and the tank isn't but 3-4' from the pump. An electric pump close would be a huge help but a serious modification. My electric pump will not pull fuel into my primary housing and its only 34" on hose between. I believe its due to the Davco design and so much of an air cavity to overcome, thus the reason it has a fill cap on top to prime it.

If it were me I would add the factory CAT hand pump primer to the engine. I'm not a fan of prefilling filters unless you plug the center so its all filtered fuel entering the engine, 20+ years ago it probably wouldn't have mattered much, we filled them back then with Automatic transmission fluid, spun them on and started them up, smoke a little but never lost prime . That's what you did in a shop with no fuel available and no trucks in there with saddle tanks.

[obedb]

CAT prefers that the filter be installed dry and then filled with the primer pump. You know that, I am sure, but with the toys that most now drive, no primer pump is the norm. When I decided to rejoin the class A  community, I thought a DP would solve the problems we often had with our 460 Ford powered Georgie Boy II. Not the case🤔. To me, diesel  trucks were very dependable. DPs would surely be the same.🙄.

[obedb]

By the way/ you and Brett are experts. I know what I know and it has gotten me by over the years, but I am not an expert. I would like to know what both of you would tell the OP to do to get his 3126E started in the mess he finds himself. Even if we never hear from him again, it will probably help people that read this website. I know what I would do but I want to hear from you guys.  Please!!

[wolfe10]

1 hour ago, obedb said:

By the way/ you and Brett are experts. I know what I know and it has gotten me by over the years, but I am not an expert. I would like to know what both of you would tell the OP to do to get his 3126E started in the mess he finds himself. Even if we never hear from him again, it will probably help people that read this website. I know what I would do but I want to hear from you guys.  Please!!

From my post above:

Also, be aware that if the level of fuel in the tank is lower than the filter head, when you remove the filter, fuel will flow all the way back to the tank, leaving you with 25+ feet of AIR.  If this is the case, it may no prime with "normal methods". The solution if this is the case is to either loosen the bleed valve on the primary fuel filter or just loosen the filter element a little.  Use compressed air in the fuel tank fill-- just put your hand over the opening with the air nozzle between thumb and index finger.  All you need is 1-2 PSI-- enough to drive fuel through the line.  Of course the best long-term solution is a ball valve on the inlet side of the secondary fuel filter.  When changing fuel filters, just shut it off.  Also, makes a heck of a good theft proofing!

[obedb]

I am not doing this to embarrass anybody. I want to know what to do if prime is lost. I estimate that the lift pump is probably  32 or more feet from the tank of our DP. It starts easily,  even after a fuel filter change and ours is one of those with only one filter. I have crawled around under the coach and I can find no evidence of an auxiallry pump. Anticipating cold starts, I always have the block heater turned on well in advance. There has gotta be a check valve somewhere , but the lift pump is all we have to get the fuel from front to rear and it is working fine. Sign me a worry wort.

[wolfe10]

As long as there is no air leak (hose, filter removal, etc) fuel will not drain back to the tank.

As I mentioned, one of the very best additions to any diesel fuel system is a ball valve on the inlet to the primary/only fuel filter.  Close it and fuel will NOT drain back to the tank when the filter is removed.

And, I am a firm believer in two fuel filters, the primary between tank and lift pump and secondary between lift pump and injection pump/engine. And, if a Caterpillar, their manual primer pump which puts an absolute end to this problem.  In fact, in writing, if your coach has the manual primer pump, Caterpillar recommends installing BOTH filters dry and using the manual pump to prime.  IT WORKS (had this system on two DP's).

[kaypsmith]

I also have the single filter, it is a two stage filter, the fuel enters at the bottom instead of the top, the bottom is the separation stage, fuel then travels upward to the canister which is the final filter. There is a ball valve immediately before the filter which I have to turn off before removing the spin off canister, with a drain **** at the bottom of the filter. I have a clear jar that I drain all of the fuel into, thus inspecting for water and any contaminants through the glass jar. After draining all fuel, I spin off the clear canister that houses the throw away filter, by the way there is a screw on cap on top of this clear canister which must be removed at the beginning of the procedure so that the fuel will evacuate the filter, there is a solenoid valve at the top of this type filter to shut down the system between the filter and fuel rail, it also is what stops bleeding between the filter and fuel rail, unless someone switches the system on with the filter removed, and in that case, you will have to bleed this part of the system also. After replacing the filter with a new one and installing new O-rings then replacing the canister, I then pour clean fuel into the canister up to the fill line, then replace the cap, then open the ball valve, if temperature is 60 degrees or above, my engine will crank with less than a half a turn. The fuel line between the tank and the lift pump if allowed to go dry does require priming, best method is as Brett suggested with air pressure, and as he stated, if the fuel in the tank is below the lift pump without shutting down at the engine end will allow backflow and cause a big problem. Not all systems are alike, but the principal is basically the same, no diesel engine can run with air in the fuel delivery system period..

[jleamont]

Obedb, the only "piece of mind" in YOUR situation would be to install the hand primer pump from CAT, if it were me I would also install the ball valve as Brett mentioned above as a 2nd line of defense. Should you ever have to change a filter on the road you don't want to be stuck, especially with your experience i.e. you know you can fix it but are missing one that one item that is stopping you.

Both projects are pretty minor assuming Tiffin gave you ample space to access the engine. I don't blame you for being a worry wart, I carry this gadget to refill my Davco if I have to change the filter on the road and I have the Davco spanner wrench to do it hanging right next to the housing. Oh, almost forgot spare filters are a must in my opinion in any situation even if your plan is to call road service. If its late in the day they might not be able to get your specific filter. I carry 6 Primary and 2 secondary.

http://www.northerntool.com/shop/tools/product_200422210_200422210

Mine looks slightly different but the same principal, its a hand siphon pump, you pump the handle and it primes itself, since my one tank fill is right next to the Davco I can fill it easily, plus the Monaco tank is like a saddle tank on a road tractor, I remove the cap and can look inside (no fuel fill tubes between the cap and the tank). I keep this in a small tote under the fuel pump in the front bay. The #2 filter is simple now, turn the key on and wait for the gauge on the dash to stop bouncing. I always think of this kind of stuff and try to plan ahead. I even went as far as replacing the filters this year using only the tools in the coach. Especially since I am still removing gunk from the fuel tank after last years bad fuel episode.

[obedb]

I have several filters with me at all times. As far as the modifications, none of you would believe where Freightliner put our one and only filter. It is doable but difficult to change the filter, and keep crud out of the replacement when positioning it to spin on. Especially lying on my back in gravel. Would love to have two filters with the first one a separator, and a primer pump. My only filter is down low, so as long as the tank fuel level is up, I will be ok there.

Sounds like you guys are set up properly. I have seen your rig Joe so I know changing filters  for you is easy.

[wildebill308]

If you have a place to install it Here is the Cat style pump.

http://www.amtequipmentparts.com/fuel-injection-system/lift-pumps/1052508-pump-priming/?_vsrefdom=adwords&gclid=CjwKEAjwjunJBRDzl6iCpoKS4G0SJACJAx-VLsUy5MZAggCZuV2aTFyjOqYJRI09xsLUN4cvdi2PoRoCEkTw_wcB

You might look at finding a hand pump you coud use by modifying a spare fuel cap to add preshure to the tank. 

In the long run I think the answer is to add a new lift pump like Joe did.

Bill

[wolfe10]

Yes, that manual primer pump mounts on a Caterpillar fuel filter head. No Caterpillar fuel filter, no place to mount it.

BTW, there are other manual primer pumps made by Racor and others.

[jleamont]

Obedb, can you snap a photo of your setup? Or does your fuel filter set up look like this (obviously without the hand primer)? Some just have a block off plate where the primer goes.

[wildebill308]

3 hours ago, wolfe10 said:

Yes, that manual primer pump mounts on a Caterpillar fuel filter head. No Caterpillar fuel filter, no place to mount it.

BTW, there are other manual primer pumps made by Racor and others.

Yes but the OP jpaflag, has a Cat and should be able to install a pump.

Bill