Cat 416 b engine died won't stay running now

[andy3882]

I have a cat 416B backhoe that the engine died on while roading to a new job site tonight. All fuel filters were Changed very recently and it ran fine until tonight. Of course when needed for an emergency water line repair it won't run. It will run with wd40 but sputters and dies quickly afterwards.

...... While priming the little hand pump on the side of the engine I noticed bubbles in the glass bowl consistent with each stroke of the little pump.

The glass bowl is full of fuel. I'm going to try and work on it in the morning just trying to get any suggestions or help I could get before I set out. The fuel priming pump looked wet with fuel like it was seeping after I pumped it about a thousand times trying to get it to start/ primed up. I didn't have time to break the bleeder at the top of the glass bowl to verify I was getting fuel. I ordered a new priming pump and it will be in in the morning.

The Air bubbles make me think I'm sucking air somewhere from the priming pump or somewhere before it back to the tank. I read that this pump has a small filter in it and if it does it's got 3000hrs on it .

Any suggestions would help me expedite this repair on the very busy road it's stranded off to the side on. I've been addicted to this site and have followed it daily for years but never posted very much on. The amount of knowledge, friendliness, and compassion to help others cannot be seen on any other site I've come across. Thank you for any advice in advance..

 

[Maurice Muenks]

While roading it you may have moved something over the inlet of the suction line in the tank. If you can maybe take air and blow back into the tank from the priming pump. I have seen where after a while sediment would build up.

 

[Delmer]

If you have a primer lever like the old Perkins (instead of a piston priming pump like a cat) then you can tell something from the pump itself. I copied this.

When you move that lever you're pulling the diaphragm back against spring pressure, release it and the spring pumps the fuel out, until the fuel pressure builds and holds the diaphragm back so there is no pressure on the lever because the spring is held back also (or there is pressure on half the stroke because the spring only pushed some of the fuel out).

There is more pressure on the lever when the inlet is plugged and the lever/diaphragm is pulling against a vacuum.

You can tell if the pump is pumping air and not full of fuel because it will have normal pressure pushing the lever, but it will spring back with the same pressure, no fuel to dampen the spring pressure.

If all else fails, and before I'd replace the transfer pump without testing it, I'd run the suction line from the transfer pump into a temporary tank and see if it will pump clean fuel, no bubbles.

 

[Dickjr.]

I bet the transfer pump took a dump. I actually got a pump from a massey ferguson dealer and took the top off the original pump , basically changed the guts and it works fine. 40$. One other problem I had , if it has the heater for the intake that you had the button in for 30 seconds the hold and turn the engine over , there is a line from the intake to the injector pump that runs behind the head , it can have a hole rubbed in it as well. I'm not sure but it might be as well just to delete the whole thing. Let us know what you find.

 

[JDfan500C]

Are you sure it didn't gell up on you?

 

[heymccall]

The rubber compression rings under the fuel supply lines can rot out.
Is there not a washable strainer screen in the top of the lift pump?
Are the upper and lower seal rings on the fuel filter still intact (and properly installed)?

To reseal the compression fitting on the fuel lines, you'll need:
5 @ 4H-2494 sleeve
2 @ 065-6380 sleeve

The return side is mostly copper ferrules. If you undo the line nut, and see a copper ferrule, reassemble and move to the next.

 

[andy3882]

Ok so i got a new lift pump from cat it appears they have revised the lift pump and made a few changes to it. It looks the same with one exception the lift pump bowel bolts appear to be installed from the bottom up instead of top down like the original one and i did not see any rubber bushings inside of where the the inlet and discharge metal lines thread in. I called cat and again they confirmed that the original part number i gave them from my parts breakdown book was changed and that only one lift pump was available......so it can't be the wrong pump. But why would they bolt the bowel from the bottom making it impossible to service without removing the lift pump? Removing and installing the lift pump was interesting to say the least very difficult to get my arms back into. The problem i have is the metal lines are not tightening up, the nut is tight but the line slides back and forth about a 1/4". Which leads me to think that the new pump needs these rubber bushings/sleeves that heymccall confirmed.

I ordered sleeves for the old pump and from the metal fuel line diagram of the lines going into the lift pump. Oddly they were different part numbers but hope that one set will work. Just surprised that the pump didn't come with them installed. Or how do you install them ? Do you place them on the line itself or put into the pump threads? ?????????

i replaced all the rubber fuel lines from the lift pump to the water separator and from the water separator to the hard line running back to the tank.They had a few rub spots on them so just to be safe i replaced them. I took and air compressor and blew a little air back to the tank to make sure there were no obstructions it was clear. Changed the primary fuel filter and cleaned the glass bowel and gaskets on the water separator.

Once i get the lift pump line figure out i will need to bleed the system. The book is very vague and states to turn key on and pump lift pump for two minutes slowly ....repeat until it starts and stays running. No mention of bleeding the injector pump or injectors. Any advice on bleeding would be appreciated!!!!!!

On a side note a young guy stopped and said that he had drove by and saw that i was working on the engine and that i had the bucket all the way in the air. He drove for a few miles thinking of his father and decided to turn around and warn me of the dangers. His father had been killed while working on a backhoe engine with the bucket in the air when the arm came down onto him unexpectedly. He was relieved to see that i had dropped the prop on the cylinder and pinned it securely. I used wd40 and the starter to get it to turn over enough to raise the bucket. SAFETY FIRST!!!! Makes you think that the unthinkable can happen.........

 

[andy3882]

Anyone

 

[Delmer]

I guess I'm anyone, but I'm no Cat expert, and the only Perkins I know are older than me.

It sounds like the pump will bleed itself with their procedure, wouldn't hurt to try that procedure then loosen the fuel return line somewhere and verify that the injection pump was returning fuel mostly free of air, you might even be able to see by looking in the tank? Loosening one injector line while cranking has always helped a lot to bleed air to the injectors (no experience with this engine though).

I'd put the rubber sleeves on the line and make sure you tighten the nuts finger tight so you don't get the threads crossed, and don't overtighten them.

 

[thepumpguysc]

AHH.. the old PERKAPILLER.. I worked on 1 that did the exact same thing. right down to the missing "grommets" in the NEW lift pump..
Follow the line to the H2O seperator.. clean and change the orings. change the big filter by the injection pump and BE SURE to fill it up before installing.
If I remember correctly, you cant remove the return line without plugging it.. it runs back to the inlet filter head and will suck air to the inlet of the pump.
They are self bleeding BUT if you loosen the lines going to the injectors.. AT THE PUMP.. it bleeds faster.. Once it starts to pump, tighten the lines back up.
Once my unit started and ran it would slow/surge after several hours.. found the tank was completely rusted and sucking rust into the new supply pump.. give it a look.

 

[gusbratz]

I have a 1987 426 cat with the Perkins engine; mine has a new lift pump that the previous owner put on it and new filters. Every once and a while it gets an air bubble in it and takes a fit. It is hard to reach the pump since its right between the frame and the engine. I put a stick of welding rod with a hook on it in the lever on the lift pump. That way I can reach it better, sort of like a pull chain on an old light. If it’s like mine then the sediment bowl is actually on the suction side so you can’t bleed that out. It will be under vacuum. If you are seeing air bubbles in that it is coming from an air leak in the line going to the tank or in the pick up tube inside the tank. I just loosen the banjo fitting up on the inlet to the injection pump and lay there pulling on the welding rod till I see fuel dripping off the other side of the engine. Then she fires right up. Sometimes moving sloshes the fuel around and it picks up and air bubble, sometimes if I am in a weird spot on a hill not level with ½ tank of fuel it will get and air bubble in it. Once I have fuel up to my inj pump it always fires right back up. I bet there is something goofy cat did inside the tank pickup line but I have not had the ambition to take it apart and look yet.

 

[doebranch]

I once had the same experience with my 1993 416B. After doing all kinds of stuff I read about the tiny filter inside the fuel pump. Once we got it off and inspected it, the filter was full of rust. We cleaned the filter, put new o rings in the lines. I had to disconnect the lines going to the injectors and have someone pump the butterfly lever on the fuel pump until we got all the air out of the line. That took some time but it finally cranked and ran. Later it started doing the same thing so we eventually had to take the gas tank off, pressure wash it, and start all over. To help resolve the rust issue that persisted in the tank, we added a small in-line cartridge filter before the fuel pump. When I see the cartridge turning red, I just put another one in it's place. Hope this helps.