My first MEP-003 start

[PaulbusMax]

Fuel at the delivery valve, but not making it to the injectors, hmmm. Have you had the pump off of the engine? Might be worth a look to see if the face gear is driving the plunger around. Sounds like the tappet is pumping, so perhaps if it's not rotating internally, the fuel never lines up with the ports to the injectors. I'm no expert, this was my first onan engine injector pump. At least timing the pump to the engine was easy. I had the high pressure lines off too, and flushed them.

 

[treeguy]

The return is putting fuel back into the tank but the IP won't send it to the injectors. It would sound right what you said about the internal rotation not lining up with the injector ports. I did time the pump to the engin, even if that was wrong shouldn't you still get fuel out of the ports? This is the 2nd IP, it is behaving the same as the original one. This one is one of the ones from Ebay. There was a little crud on the delievery needle that I cleaned off, there was no O ring on this valve like the TM shows. Do you have one on yours?

 

[treeguy]

Well I've got it figured out. I'm more screwed than I thought. I took apart the original IP down to the plunger (past the spring). The guts don't look like the TM at all, I have a plunger shaft that is 3 sided square and under the face gear is a flat cross looking piece of metal that engages the 3 sided square which turns it. The cross shape fits into a recessed area of the face gear. Of course because the unit sat all this gummed up so upon hitting the starter the face gear turned but the plunger was locked up an the cross piece of metal split into 2 pieces. So now the face gear turning does nothing. This is going to be some interesting sergical welding. I have a horrible feeling that the new IP I just bought bit the dust just like the original one. So the moral of the story I guess is don't let your precious green iron sit around without exercise!

 

[PaulbusMax]

I'd be surprised if the replacement IP failed the same way, and yeah, my IP was a little different internally than the TM showed too. You've got fuel returning to the tank, so supply sounds good. Double check the installation timing. Make sure the PC visible in the pointer window is when number one cylinder is near TDC. It would be easy to have the PC letters lined up, but with wrong cylinder. I took the valve cover off to make sure, and to just have a look inside. Open the "throttle" when cranking.

 

[treeguy]

Thanks for the timing info, I was just about to put the original pump back in. Is that the only way to know if its #1? I was able to weld the 2 pieces back together. I think the replacement IP was sitting on a shelf for who knows how long so it probably jammed up to and I snapped the same metal piece. It makes sense, no high press fuel output because the face gear wasn't turning the plunger shaft to alternate the output. This was the last thing I would have ever thought of, I hope that others can benifit from this info!

 

[treeguy]

The broken piece in the IP was totally the problem, I fired it up this morning and it SCREEMS! When I was calibrating the IP timing I looked into the crank case (thru the pump opening) an noticed that when the pointer is on PC only the #1 piston is up every time. So it seems that PC only indicates #1 TDC. Does anyone know if its ok for electrical use if the HZ fluxuates? When I set the RPM to read 60HZ it stays around there but does float up and down a little. I kind of think this is normal but don't want to ruin any devices plugged into the genny. The only down fall so far is that the cooling fan blows all the exhaust in your face when at the control panel. Thank you very much Paul for you input I'm not sure if I would have thought of the whole face gear spinning / plunger not turning idea.

 

[Carl_in_NH]

PC on the flywheel only indicates port closing on #1 - you have to remove the rocker cover to make certain it's the proper part of the cycle; remember, there's two turns of the crank for one turn of the cam . You might have timed your pump initially to the wrong phase of the crank. This information is in the TM.

Glad to hear you got it working.

If the frequency moves up and down a few Hz it's not going to bother anything you might power from the generator; you can get better control of this by adjusting the govenor; again, the TM has in information on how to accomplish this task and stop the RPM / Hz 'hunting'.

 

[Speddmon]

Thanks for the timing info, I was just about to put the original pump back in. Is that the only way to know if its #1? I was able to weld the 2 pieces back together. I think the replacement IP was sitting on a shelf for who knows how long so it probably jammed up to and I snapped the same metal piece. It makes sense, no high press fuel output because the face gear wasn't turning the plunger shaft to alternate the output. This was the last thing I would have ever thought of, I hope that others can benifit from this info!

I think everybody missed this one so I'll take a crack at it. Carl is right, the "PC" mark will line up on both the compression stroke and the exhaust stroke. You may have had it off the last time you installed the new pump. The only way to tell for sure is to pull the valve cover and make sure the valves are closed.

The reason your mark lines up every time the #1 cylinder is on top and only #1 is because you have the MEP-002a (2 cylinder). Paul, the OP, has an MEP-003a (4 cylinder). So, the PC mark should line up on #3 cylinder as well as #1 on Pauls machine.

The broken piece in the IP was totally the problem, I fired it up this morning and it SCREEMS! When I was calibrating the IP timing I looked into the crank case (thru the pump opening) an noticed that when the pointer is on PC only the #1 piston is up every time. So it seems that PC only indicates #1 TDC. Does anyone know if its ok for electrical use if the HZ fluxuates? When I set the RPM to read 60HZ it stays around there but does float up and down a little. I kind of think this is normal but don't want to ruin any devices plugged into the genny. The only down fall so far is that the cooling fan blows all the exhaust in your face when at the control panel. Thank you very much Paul for you input I'm not sure if I would have thought of the whole face gear spinning / plunger not turning idea.

Again, Carl is right, the frequency shouldn't be too big of a deal. Plus the meters on these generators aren't the most accurate or reliable things going. You really should check and verify the reading and fluctuation with a good multimeter that has a frequency setting. As long as you are within a range of Hz you should be fine to run anything you want to. I would venture to say that if you were between 57 and 63 Hz you should be just fine. But that's only my opinion. Try going through the TM and adjusting the governor and see how that does for your problem.

 

[Speddmon]

The broken piece in the IP was totally the problem, I fired it up this morning and it SCREEMS! When I was calibrating the IP timing I looked into the crank case (thru the pump opening) an noticed that when the pointer is on PC only the #1 piston is up every time. So it seems that PC only indicates #1 TDC. Does anyone know if its ok for electrical use if the HZ fluxuates? When I set the RPM to read 60HZ it stays around there but does float up and down a little. I kind of think this is normal but don't want to ruin any devices plugged into the genny. The only down fall so far is that the cooling fan blows all the exhaust in your face when at the control panel. Thank you very much Paul for you input I'm not sure if I would have thought of the whole face gear spinning / plunger not turning idea.

I almost forgot...the exhaust issue. Are you missing any sheet metal on the set?? The exhaust should exit straight out over the batteries with a 45 degree pipe bend on the exhaust pipe. The blower should circulate all the air inside the sheet metal parts and blow it out through the "shutter" box around the muffler, again over the batteries and nowhere toward the control panel. If you are missing any sheet metal, I would recommend finding the missing metal parts as they are an integral part of the cooling system being that this is an air cooled engine. Also, if missing any parts, it goes without saying don't run the set for any long periods of time as it can easily overheat.

 

[PaulbusMax]

Really glad you got it running !!! Good job.

 

[treeguy]

Thanks, this website is such a resource. The exhaust blows back because someone had put on a 18" muffler on a 45 deg. angle back so the fumes go up and then the fan air blows it down depending on the wind. I suppose I'll take it off, the natural downward output makes sense that the shutter vent will blow it tward the batteries. Luckily my unit is not missing any of the sheet metal, the only thing missing are the ground rods (which should be readily available comercially). I also don't have the ASK kit which seems like gold. Has anyone tried to fab one themselves? Regarding the IP timing, the genny runs, could I still have it timed for the wrong stroke or would it not run at all if that was the case?

 

[Carl_in_NH]

Careful of a long muffler hanging off the unit; people have reported cracks in the manifold when hanging stuff off there. If you want a muffler, it's best to mount it solidly somewhere, and use a piece of flex between the generator output and the muffler.

No, it's not possible for it to run if you've got the IP timed on the wrong TDC; my initial though was that this was a possible cause for it not running once you had replaced the pump, since you seemed to have not been aware of the requirement to be certain the valves were closed when approaching the PC mark on the flywheel. Since it's running, you're all set - but the comment might help someone in the future looking at the thread.

As for fabbing the ASK, I suspect it's just too much work (at least it is for me). The chances of finding a kit by itself are just about zero - since anyone with a kit or a parts unit that had the ASK installed would transfer it to another genset.

They are loud, but once inside the house - provided the house is closed up - it's not too bad. There's a lot of noise from the engine itself and the blowers for the engine and generator head - and that's what the ASK helps with. The exhaust really isn't all that loud even without a muffler.

 

[treeguy]

Thanks Carl, I took the muffler off and the noise isn't that bad.

 

[Speddmon]

you're not going to hear much difference in the noise output without that added muffler. Most of the noise you are hearing is engine noise and the fans like Carl mentioned, and not exhaust noise. There is already a muffler on the set. It's inside the shutter box behind the louvers. I don't know of anybody who has the ASK for the 002a, but I might have a source for the ASK for a 003a 10KW.

 

[treeguy]

I just disassembled my replacement IP and couldn't find anything wrong with it until I was putting it back together - NO BUTTON ! IT CAME WITH NO BUTTON! Who woulda thought? Oh well, one more to tack up to the School of Hard Knocks. At least I could use the new delievery spring and valve.

 

[Carl_in_NH]

They all come with no button; the button must be selected from the standard sizes to time the pump correctly to your engine. Again, the TM has all the data on how you do this - and the AMBAC web site has even more detailed information on the pump and timing it to the engine.

The price on the silly little button from AMBAC? More than $75 once you get it shipped. If the thing were not such a complex shape (and hardened, to boot) I would have made my own in the shop - but it's more than $75 worth of time and work to make the darn thing.

 

[LuckyDog]

If you are getting nothing from the return line, I would be checking fuel lines before I pull the IP off. I think the return line should return as much fuel to the tank as you are pumping no matter the position of the stopper rod inside of the IP (someone please correct me if I am wrong). There have been members who have had some of the 90 degree fittings in the fuel system clogged up with crud and not allowing the fuel to flow. Before you undertake the pulling of the IP, make sure you are getting as much fuel back from the IP to the tank as you are putting to the IP.

I am having a similar problem with trying to start my -002 for the first time.

Speddmon,
Do the fuel pumps stop when the pressure is 6-9psi? or just run a little slow? I have hardly any fuel flow out the return line. The pumps run up the pressure ok, then stop and only cycle every few seconds.

 

[treeguy]

LuckyDog, when you turn the control switch to run/prime the fuel pumps do a sort of prime/purge (and I believe return fuel back to the tank ?) anyway the pump clicking will slow down once primed so what you said sounds normal. Having hardly any fuel flow from the return line, I don't know, this may be normal because the system is presurizing and collecting in the Injection Pump and only a little is forced back in to the tank. I'm not an expert but I think mine does what you are saying. What is the problem with your Genny, does it crank but not start? Mine was the same way, check out my post #24 above. I reviewed the TM and opened up my IP and found the problem. Good luck!

 

[treeguy]

You can check if its the IP if you crack (slightly loosen) one of the high pressure lines at one of the injectors and crank the engine and see if you get any fuel from it. If not, its the IP, if fuel then I'd say dirty/stuck injectors. You can get parts from a company called Delks, I also have an extra new IP but it doesn't have a timing button as you can read from a post above.