Looking for info on Cat 3406 SR4B Genset

[Mobiltech]

Yes the fine adjustment rod and nuts are missing as mentioned above. It wont lock in the way it is now but can still be run like a normal throttle.
It probably wouldnt hurt to get the pump inspected. The thrust washers and governor weights do get worn in one spot because it runs at 1800 all the time.
I usually rebuild the governors on a regular basis to prevent runaways.

 

[Mobiltech]

I think it should look like this.

 

[John C.]

I've got the parts for the throttle identified and will send the parts list to the owner in the morning for approval. I am nervous about starting the engine and having it misbehave. The strainer was full of bio jell but the filter was clean. Is it possible to pull a cover on the to make sure the fuel control rack is free to move?

 

[John C.]

Thanks for posting the parts list.

 

[Mobiltech]

Its got an oil pressure fed shutoff. Shuts off for lost oil pressure or over temp.

 

[Mobiltech]

Yes you can pull the small cover with 2 bolts up by where the pump mounts. You will see the rack in there with a notch in the top. Put a screwdriver in the notch and see if the rack moves. You will need it at full throttle and fuel shutoff in run position to freely move the rack. Number 10 is the cover.

 

[John C.]

Thank you!
That is a easy way for a go / no go test I can explain to the owner on what needs to be done.
I appreciate the info and will let you know what I find.

 

[grandpa]

If you do get to the point of firing it up my 3304 SR4 has a low oil pressure switch that when you shut it down will pop out do to low pressure. You have to push the button in every time to restart.

 

[John C.]

I'll look for it.

Thanks!

 

[John C.]

I pulled the cover off and see the rod in the back of the hole. I could not move it at all not matter where the throttle was set. The rod is also extended all the way to the left side of the hole. I also pulled the mechanism in the back with the black knob and see that it presses on the shutdown linkage in the governor. The external shutdown lever on the side of the governor works when the black knob is pulled out. I pulled the cover that is in front of the injector pumps and see some rust just at one end of the gallery. I'm wondering if one or more of the injector pumps could be stuck. With that rod froze I suppose that means the pump needs to get torn down.

I also got into the control box for the generator. It is covered in red dust and sticks to everything. The same dust is all through the generator windings. I pulled the side cover off and checked the big wires. They have metal tags on them. The three that look like the output leads have tags that say 1, 2, 3. There are two wires each and a small wire. I'm figuring these are likely the output wires because they are routed through the circular pick ups. I checked resistance to the generator frame on each with an ohmmeter on the 200K scale and they all start at 17 and gradually go up to 21. I know they need to be checked with a megohm meter but I don't have one at hand. My suspicion of the past history of this unit is that it was in a flood.

 

[Truck Shop]

If that injector pump has rust inside the owners will probably choke at the price to rebuild it. MO

 

[Mobiltech]

You would need the shutoff with the black knob removed to move the rack. The rack will be over to the left when you look in the hole.
The long side cover is the fuel supply gallery. If there is rust in there and no fuel I would bet the plungers and barrels are seized. That would keep the rack from moving.
I wonder if there is water in the oil side of the fuel injection pump too. If there is the rebuild would get pricey.
What’s the engine oil look like?
Is there a voltage regulator mounted inside the gen housing or just wires?

 

[John C.]

Thanks for the replies!
I removed the black knob and tried to move the rack. I moved the throttle control to all positions while trying to move the rack. The rod never moved. There was fuel in the gallery and just a spot of rust on the lowest side. I haven't checked the oil side of the fuel pump but will when I get back there. The engine oil looks like new. I've called the local Cat dealer about rebuilding the fuel pump. The generator people don't do that apparently and the guy I spoke to was pretty much uneducated about generators. He told me they don't rebuild them, only swap them out with rebuilds. I called the machine side of the company as I know they have a rebuild area and a competent wrench who knows all the Cat products. I'm waiting on a call back.

I don't see anything that looks like a voltage regulator in the control box that sits above the generator. What is there, is a control box that is the EMCPII style control box. Everything on the tags on the box show 24 volt which is the alternator and starter electric system. I've read in the O&M manual that some units don't have voltage regulators and are meant for oil field use. It does have a dial to fine adjust voltage next to the readout panel. I pulled some of the sheet metal yesterday when I was there and noticed that on the end of the generator is a smaller generator that I think is a field generator. It's kind of the same thing as found on old Lincoln DC welders.

 

[Birken Vogt]

There should be 2 wires from the little field generator going off somewhere, that is where you will find the voltage regulator. The voltage regulator feeds DC into the field generator which is rotating on the end of the shaft and then the field generator feeds power to the rotating main field which is the large bulky rotating part. If there is a voltage adjust knob those wires should lead to the voltage regulator as well.

 

[John C.]

Thanks, I remember seeing the two wires attached to the back of the field generator and I think two wires going into a loom. I'll look again when I get back up there.

 

[Mobiltech]

When I say remove black knob I mean take the 2 bolts out of the cap and remove the whole shutoff including the hose. There will be an oil filled plunger spring loaded to off position.

 

[John C.]

Update on the project:
The fuel pump was pulled and taken to the local Cat dealer. The mechanic there pulled the plunger and barrel assemblies and found number 1 to be stuck hard. All the rest of the P&Bs are damaged. All will be replaced with new. Since the engine condition is unknown, it was decided to make the pump operational and get the engine to run so we know what we have. We aren't doing anything with the oil side and governor at this time. We do know with the damage to the P&Bs that the nozzles are likely to be junk as well. The cost for an exchange fuel pump was just over $5,400. The current work and parts will run a little over $3,000 not counting the remove and replace. Asking prices for used gensets of this size are anywhere from $28,000 to around $40,000 depending on configuration. I should have the pump back next week to re-install.

 

[John C.]

I put the fuel system back on the engine last weekend. The owner bought new batteries and I built all new 2/0 battery cables and solder on ends. Got all that finished today along with a battery disconnect and a remote starter button. Bumped the engine over a little at a time after I primed the fuel system an noticed a bit of smoke. Turned the motor over regular and saw the oil pressure gauge go up and the darn thing took off running. No muss, no fuss. Ran smooth so I shut it down and decided to check the monitor panel and the manual start function on that. It has a barrel switch with markings for cool down, manual start and auto function. I put it in manual start and away the thing went. Again it was smooth as you please and the monitor panel worked. Show 485 volts when I adjusted the engine for 60 hertz. I shut it down as I saw a truck driving up. It turned out to the the owner and he didn't know that I had it running. I called him over and said watch this. The smile on his face was priceless when that engine kicked off so quick. He has been sweating the buyers remorse bit for about six weeks. There is a lot more work to do but the big issue appears to be passed us for now.

 

[Truck Shop]

That's great it took off without a hitch.

 

[Nige]