bwdozerman Posted June 5, 2023 Share Posted June 5, 2023 1987 Superliner w/e9. Engine was running fine. It sat for a couple of years and the clutch was stuck. I pulled it into gear and it moved forward and stalled. Now, it won't start. Acts just like the fuel shut off is closed. Could the injector pump be damaged? Any ideas are appreciated. Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/ Share on other sites More sharing options...
JoeH Posted June 5, 2023 Share Posted June 5, 2023 On the inline mechanical engines I've heard the fuel rack can get sticky from sitting. If you disconnect the fuel shutoff linkage from the lever, does it have any resistance? I'm just guessing, I've never worked on an e9 nor do I know how the fuel pumps function compared to inlines. Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532493 Share on other sites More sharing options...
JoeH Posted June 5, 2023 Share Posted June 5, 2023 That it was running fine until you stuck it in gear tells me engine should be fine, unless you broke a crankshaft getting it in gear with a stuck clutch. Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532494 Share on other sites More sharing options...
bwdozerman Posted June 5, 2023 Author Share Posted June 5, 2023 Mine has the "V" injector pump. I did stroke the fuel shut-off lever, and it is normal. The motor cranks normally. It just acts like it's not getting any fuel, which it isn't. I was thinking the drive gear to the injector pump may be damaged, or something else inside the pump shifted. The starter can move the truck easily, which makes me think there's no mechanical damage. The hand primer pump doesn't seem to circulate back to the tank freely now. Any thoughts? I thank you for your reply. Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532514 Share on other sites More sharing options...
Freightrain Posted June 5, 2023 Share Posted June 5, 2023 Crack a line and see if the transfer pump is moving any fuel? 1 Quote Larry 1959 B61 Liv'n Large...................... Charter member of the "MACK PACK" Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532518 Share on other sites More sharing options...
JoeH Posted June 5, 2023 Share Posted June 5, 2023 Modern biodiesel grows algae, so your tank suction line could be clogged with that. Or you're outa fuel? Sucking air in somewhere? Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532522 Share on other sites More sharing options...
bwdozerman Posted June 5, 2023 Author Share Posted June 5, 2023 Is there any kind of electrical shut-off for the fuel transfer pump? I'll check out all y'alls tips. When the motor lugged down to stall, could it have turned the injector pump backwards? There may be a check valve right at the pump. It's a little wet with fuel now. Maybe forced shut to hard. I'll look it over Friday. Thanks again! Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532524 Share on other sites More sharing options...
Vladislav Posted June 5, 2023 Share Posted June 5, 2023 Get a nut at any injection line loose. Crank the engine. You you should see fuel pulsating from under the nut. If it's there the plunger in the pump operates. You may check all 8 of them. If no fuel pressure in the injection line there may be a boquette of issues including prime or air or rack locked in the shut-off position or others. Quote Никогда не бывает слишком много грузовиков! leversole 11.2012 Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532527 Share on other sites More sharing options...
bwdozerman Posted June 5, 2023 Author Share Posted June 5, 2023 I'd love to hear the '59! Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532528 Share on other sites More sharing options...
bwdozerman Posted June 5, 2023 Author Share Posted June 5, 2023 The throttle shaft turns OK. Maybe it can disengage from the rack. I'll loosen a few injector line nuts, but, don't expect to see fuel. Everything seems fine, except no fuel into engine. Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532529 Share on other sites More sharing options...
Back In Black Pulling Posted June 5, 2023 Share Posted June 5, 2023 little 2 bolt plate where pump mounts see if gear is turning when cranking pull top of governor or one of the 2 screw caps on front of pump to see if rack moves freely if rack is stuck the throttle n shut of will still move heres good video on setting the timing 2 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532545 Share on other sites More sharing options...
bwdozerman Posted June 6, 2023 Author Share Posted June 6, 2023 Excellent! I'll check this out on Friday. Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532553 Share on other sites More sharing options...
fjh Posted June 6, 2023 Share Posted June 6, 2023 19 hours ago, bwdozerman said: The throttle shaft turns OK. Maybe it can disengage from the rack. I'll loosen a few injector line nuts, but, don't expect to see fuel. Everything seems fine, except no fuel into engine. Take the fuel line off at the inlet to the pump crank the engine and see if fuel is coming to the pump! if there is no fuel you have a supply issue ! Also check out my post in odds and ends V8 Therapy! just an odd ball failure ! The engine just up and quit ! It can happen ! If you got fuel to the pump and the rack is ok! U may need to check the timing ! If you eliminate all the other options posted here post and I can walk you thru the steps to check this failure It is quite simple! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532571 Share on other sites More sharing options...
bwdozerman Posted June 15, 2023 Author Share Posted June 15, 2023 Are the screw caps that expose the fuel rack on either side of the timing cover? The tachometer is connected to one of them. The throttle lever pivots freely, but, doesn't appear to be moving anything internal. Stopped by the Mack store to try and get an exploded parts view, but, they couldn't get anything off their system. I haven't actually opened anything, just took the photos below. The fuel inlet has the silver fitting, mabe a check valve. Let me know what to open to expose the fuel rack. Thanks, Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-532999 Share on other sites More sharing options...
Back In Black Pulling Posted June 16, 2023 Share Posted June 16, 2023 (edited) Long cap is puff limiter which limits rack travel until certain amount of boost from intake Tack is down in front between air comp n steering pump that fitting is return check valve is in pump or should be if it was me i would give it a good wash before taking anything apart Edited June 16, 2023 by Back In Black Pulling 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533045 Share on other sites More sharing options...
fjh Posted June 16, 2023 Share Posted June 16, 2023 Pull the cap two screws right front that will expose the rack clean it first as mentioned! Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533092 Share on other sites More sharing options...
bwdozerman Posted June 19, 2023 Author Share Posted June 19, 2023 I cleaned up the area and remove both screw caps and the timing cover. Rack moves freely. Pulls all the way in when fuel shutoff lever is rotated to shutoff position, and pushes out when throttle lever is rotated. The hand primer lifts fuel easily through the filters. After cranking to start, it seems like the hand primer pressure is lower. There is no external lift pump on my truck, that I can see. Is there a way to check the low pressure lift pump section of the Ambac pump? Maybe it's something else. Thanks, Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533288 Share on other sites More sharing options...
bwdozerman Posted June 19, 2023 Author Share Posted June 19, 2023 Pump drive gear turns when cranking. Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533289 Share on other sites More sharing options...
Back In Black Pulling Posted June 19, 2023 Share Posted June 19, 2023 (edited) do you get fuel out of return maybe stuck open not making pressure try a little ether maybe air bound or lift pump might be shot Edited June 19, 2023 by Back In Black Pulling Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533312 Share on other sites More sharing options...
bwdozerman Posted June 20, 2023 Author Share Posted June 20, 2023 I removed the fuel return check valve. It shuts off good and has appropriate spring back pressure. I will try the ether like you suggested. There is no smoke at all when cranking, making the fuel supply issue likely. Please say exactly where the fuel lift pump is located. I was thinking it was inside the injector pump, like a farm tractor. Thanks, Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533349 Share on other sites More sharing options...
terry Posted June 20, 2023 Share Posted June 20, 2023 3 hours ago, bwdozerman said: I removed the fuel return check valve. It shuts off good and has appropriate spring back pressure. I will try the ether like you suggested. There is no smoke at all when cranking, making the fuel supply issue likely. Please say exactly where the fuel lift pump is located. I was thinking it was inside the injector pump, like a farm tractor. Thanks, Should be able to follow fuel lines to see where lift pump is, terry 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533365 Share on other sites More sharing options...
Back In Black Pulling Posted June 21, 2023 Share Posted June 21, 2023 Should be what hand primer is screwed into in center of v of pump 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533372 Share on other sites More sharing options...
fjh Posted June 21, 2023 Share Posted June 21, 2023 On 6/19/2023 at 6:31 AM, bwdozerman said: I cleaned up the area and remove both screw caps and the timing cover. Rack moves freely. Pulls all the way in when fuel shutoff lever is rotated to shutoff position, and pushes out when throttle lever is rotated. The hand primer lifts fuel easily through the filters. After cranking to start, it seems like the hand primer pressure is lower. There is no external lift pump on my truck, that I can see. Is there a way to check the low pressure lift pump section of the Ambac pump? Maybe it's something else. Thanks, bar the engine over till you see the hole in the adjustment hub in front of the gear on the pump dead center in that opening and then check to see if the timing marks are any where close to the pointer! if the timing is within the numbers on the damper your timing is close enough to run 17 -24 ish! if the timing marks arn't close pull the compressor and and check the gear same with the power steering pump! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533382 Share on other sites More sharing options...
bwdozerman Posted June 26, 2023 Author Share Posted June 26, 2023 Timing checked out to be ~19 to 20. Hand primer pumped up tight, but, no return flow to the tank. No return flow to the tank while cranking either. Removed lines to lift pump. Very obvious that no fuel at all is passing through the pump. I don't have any idea of how the passage from inlet to outlet works. Most likely springs set to control precise pressures. Something must be seized to prevent all flow. I turned the motor with a bar and the pump gears do turn. What's the best repair strategy? If I go to the Mack store, they'll most likely not be able to look up or supply a replacement. Thanks again, Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533596 Share on other sites More sharing options...
fjh Posted June 26, 2023 Share Posted June 26, 2023 The Mack store will give you a blank stair unless you happen to run across a parts man in a wheel chair and hearing aids ! 🤣 Appears to me someone has put in an extra check valve on the fuel return under the stop lever there ? remove that number 6 line fuel should flow when you pump the primer up! The other thing is stick your finger in the hole where the pump came from and feel around in there I have seen this idler gear fall off ! it is held on by a c clip! it runs off the governor drive! I have also seen this gears idler shaft so worn the gear flops around a lot I would usually check this if I have a pump off as you have there! I really sounds to me like you got a restriction on the inlet side from the tank! By what your describing! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72921-injector-pump-damage/#findComment-533597 Share on other sites More sharing options...
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