szafram Posted March 6, 2012 Share Posted March 6, 2012 Hello all,I have a 1976 CF685 pumper, and my fuel injector pump shutoff valve has frozen...I have been advised how much it would cost to have the thing rebuilt, but I want to explore my other options. The one I am considering is forcing the valve to the open position, then locking it in place, then putting a new manual (or electric) shutoff valve at the fuel entrance into the injector pump (still on the low pressure side). Does anyone have experience with this, or an reasons for or against doing it? Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/ Share on other sites More sharing options...
b61mack Posted March 6, 2012 Share Posted March 6, 2012 Hello all,I have a 1976 CF685 pumper, and my fuel injector pump shutoff valve has frozen...I have been advised how much it would cost to have the thing rebuilt, but I want to explore my other options. The one I am considering is forcing the valve to the open position, then locking it in place, then putting a new manual (or electric) shutoff valve at the fuel entrance into the injector pump (still on the low pressure side). Does anyone have experience with this, or an reasons for or against doing it? Thanks Have you had it running lately or has it been sitting for a few years, if it has the rack is stuck you going to have to take the side cover off and spray PB blaster on the barrels and work them back & forth untill they loosen up. if it wont start dont try any more until you get it free up, it will run wide open and damage your engine. did you disconnect the shutoff cable to see if you can move it. Ron Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-105796 Share on other sites More sharing options...
b61mack Posted March 6, 2012 Share Posted March 6, 2012 Hello all,I have a 1976 CF685 pumper, and my fuel injector pump shutoff valve has frozen...I have been advised how much it would cost to have the thing rebuilt, but I want to explore my other options. The one I am considering is forcing the valve to the open position, then locking it in place, then putting a new manual (or electric) shutoff valve at the fuel entrance into the injector pump (still on the low pressure side). Does anyone have experience with this, or an reasons for or against doing it? Thanks I forgot to ask what part if Indiana are you from. Ron Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-105798 Share on other sites More sharing options...
szafram Posted March 6, 2012 Author Share Posted March 6, 2012 Yea, it has been running recently. I ran it in late October/early November, than on Christmas again, and that is when it froze, while it was still running, and I had to forcefully shut off the valve from inside the engine bay. I will pull the cover off tomorrow and spray some PB blaster on it. I did disconnect the cable (as I had hoped that was all that was stuck), but as soon as I did, the cable moved fine and the valve was still stuck. And I am in Lake County, about and hour/hour and a half from Delphi. Thanks for the response! -Matt Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-105830 Share on other sites More sharing options...
szafram Posted March 7, 2012 Author Share Posted March 7, 2012 Ron, pulled the side panel off, but didn't have a lot of time to move the barrels and such, but I think they should be free as the truck was recently driven. I will try that more tomorrow though, and hopefully that frees it up. In the meantime, here is a link to a picture of the exact pump that I have (http://www.oldengine.org/members/diesel/Injection/AmbacManual13.htm), and #3 is the component that is frozen and won't turn. Should I still keep working the barrels when I get a little more time to try and free that up, or is there a different, possibly more effiecient way to do it? Thanks! Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-105979 Share on other sites More sharing options...
b61mack Posted March 7, 2012 Share Posted March 7, 2012 Ron, pulled the side panel off, but didn't have a lot of time to move the barrels and such, but I think they should be free as the truck was recently driven. I will try that more tomorrow though, and hopefully that frees it up. In the meantime, here is a link to a picture of the exact pump that I have (http://www.oldengine...bacManual13.htm), and #3 is the component that is frozen and won't turn. Should I still keep working the barrels when I get a little more time to try and free that up, or is there a different, possibly more effiecient way to do it? Thanks! There is a little air cylinder on the front of the pump take it out and slip a long bolt i think 1/4" in the hole and tap on in, soak it good with blaster. if it has only 2 or 3 barrels stuck you should free it up easy, maybe you wont have to take the pump off. Ron Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106016 Share on other sites More sharing options...
szafram Posted March 9, 2012 Author Share Posted March 9, 2012 Ron, I had a little more time to play with it, and all the barrels seem to move freely with little or no resistance. I can't find the air cylinder you are talking about on the front of the pump, but I did find this owners manual (http://www.ambac.net/images/model_ape_6bb.pdf) of the one that I have. From the exploded view, part number 56 and number 57 are the ones that are frozen. The front side of the pump (assuming front is the side farthest away from the governor) is completely covered and looks to be hooked into the engine at that point. Any other thoughs on what I can do, or which number on the exploded view is the air cylinder you were refering to? Thanks again for all your help! Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106229 Share on other sites More sharing options...
b61mack Posted March 9, 2012 Share Posted March 9, 2012 Ron, I had a little more time to play with it, and all the barrels seem to move freely with little or no resistance. I can't find the air cylinder you are talking about on the front of the pump, but I did find this owners manual (http://www.ambac.net...del_ape_6bb.pdf) of the one that I have. From the exploded view, part number 56 and number 57 are the ones that are frozen. The front side of the pump (assuming front is the side farthest away from the governor) is completely covered and looks to be hooked into the engine at that point. Any other thoughs on what I can do, or which number on the exploded view is the air cylinder you were refering to? Thanks again for all your help! It should be screwed into #71 it is a pufflimiter, someone might have taken it off or it never came with one. are you sure you govoner is not woreout. Ron Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106265 Share on other sites More sharing options...
szafram Posted March 12, 2012 Author Share Posted March 12, 2012 After today I am positive it isn't the governor. I pulled it off the side to access the shut off shaft, and it moved like butter once I took it off. The shaft however still will not move at all. I can manually move the rack no problem as well, but that shut off shaft is still frozen. I took the snap ring off that holds it in place, hoping I would be able to take the shaft out and clean everything up and regrease it. Not only will the shaft not turn, it is frozen in place and will not come out either. All of the pieces are there and appear to be in good shape, its just stuck and wont move. Ive soaked it in PB blaster a few times, but still no luck. Any thoughts/ideas? Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106777 Share on other sites More sharing options...
Rob Posted March 12, 2012 Share Posted March 12, 2012 After today I am positive it isn't the governor. I pulled it off the side to access the shut off shaft, and it moved like butter once I took it off. The shaft however still will not move at all. I can manually move the rack no problem as well, but that shut off shaft is still frozen. I took the snap ring off that holds it in place, hoping I would be able to take the shaft out and clean everything up and regrease it. Not only will the shaft not turn, it is frozen in place and will not come out either. All of the pieces are there and appear to be in good shape, its just stuck and wont move. Ive soaked it in PB blaster a few times, but still no luck. Any thoughts/ideas?I have had a couple act like you explain. the seal shown as number 55 in the exploded diagram has probably allowed moisture to creep onto the shaft binding against the aluminum housing. You can take a propane torch and heat the aluminum housing around the shaft till warm, then spray either water, or electronic circuit cooler onto the steel shaft to free it up. You can also submerge the whole governor assembly in fuel and slightly work the shaft back and forth while applying pressure to extract it from the housing. Use crocus cloth to clean and polish both the shaft, and the bore before putting it back together with a new seal.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106779 Share on other sites More sharing options...
szafram Posted March 12, 2012 Author Share Posted March 12, 2012 Ah, that makes perfrect sense, thanks! I'm probably going to try the fuel method since the whole pump is still on the truck, and I really dont want to take it all off if I can avoid it. Is it just a rubber seal thats holding it in place then? Mines painted over, so I'll have to get past that part first...Do you know where I can get a replacement seal for one at? Thanks again!! Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106796 Share on other sites More sharing options...
Rob Posted March 12, 2012 Share Posted March 12, 2012 Ah, that makes perfrect sense, thanks! I'm probably going to try the fuel method since the whole pump is still on the truck, and I really dont want to take it all off if I can avoid it. Is it just a rubber seal thats holding it in place then? Mines painted over, so I'll have to get past that part first...Do you know where I can get a replacement seal for one at? Thanks again!!Any fuel injection shop will be able to get the seal, or a good bearing supply house can do the same by measurements. Don't be afraid to submerge the governor housing in fuel as everything in there is submerged in engine oil as the engine is running. I'm assuming you have the rear governor off of the pump? It just bolts on if you do have it off already.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106797 Share on other sites More sharing options...
szafram Posted March 13, 2012 Author Share Posted March 13, 2012 Yea, I picked up the seal today, and Im hoping to change it tomorrow. And yes, I have the governor off already, but the pump is still on the truck. Thanks again for the help! Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-106957 Share on other sites More sharing options...
szafram Posted March 14, 2012 Author Share Posted March 14, 2012 Rob, I dont have the regular radial seal shown in that drawing, mine is an o-ring. Will applying heat to the spot where the shaft enters the housing still work? Or is there something I can spray on that joint to free it up? Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-107165 Share on other sites More sharing options...
Rob Posted March 14, 2012 Share Posted March 14, 2012 Rob, I dont have the regular radial seal shown in that drawing, mine is an o-ring. Will applying heat to the spot where the shaft enters the housing still work? Or is there something I can spray on that joint to free it up?You can still use heat as you are replacing that seal no matter what it is. You need to soften the suspected corrosion between the shaft and the housing. Heat will expand the housing, cold will shrink the shaft without shriveling it........Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-107186 Share on other sites More sharing options...
szafram Posted March 15, 2012 Author Share Posted March 15, 2012 I tried the heat method, but I didnt have any luck with it. Im not sure if it just wasnt hot enough, but it was weeping out moisture from the aluminum housing every time I tried. Do I just need a more pwerful torch then, or am I out of luck with that method? Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-107441 Share on other sites More sharing options...
szafram Posted March 16, 2012 Author Share Posted March 16, 2012 Yep, higher heat is what it needed. It's now cleaned and back in place. Thanks for the help!! Quote Link to comment https://www.bigmacktrucks.com/topic/23648-mack-cf-600-fuel-pump-problem/#findComment-107655 Share on other sites More sharing options...
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