2007 Mack CV713, AMI 370 engine, unit pump came off

[Mack Snow Fighter]

Hello, 

Was loaded and running the truck hard when suddenly there was a loud ticking sound under the hood and fuel all over the road. Needed to pull off the road and get the truck towed. Turns out that a unit pump had come out of the block. The one bolt looks like someone would have cut the head off, the other one was broken off about flush.  Both studs came out very easily. 

Nothing seems to be wrong with the unit pump. What is the root cause.  Should I just put it back together and see what happens, or should I replace unit pump and injector? Thanks for your  help! 

[fjh]

25 minutes ago, Mack Snow Fighter said:

Hello, 

Was loaded and running the truck hard when suddenly there was a loud ticking sound under the hood and fuel all over the road. Needed to pull off the road and get the truck towed. Turns out that a unit pump had come out of the block. The one bolt looks like someone would have cut the head off, the other one was broken off about flush.  Both studs came out very easily. 

Nothing seems to be wrong with the unit pump. What is the root cause.  Should I just put it back together and see what happens, or should I replace unit pump and injector? Thanks for your  help! 

Pull up the roller from under the pump ! check it if it looks good check for the pin that the roller slides on in the block  if its still there and in good shape put it back together and drive it`! I would check the other pump bolts and if you can just replace them all this happens from time to time its not common or uncommon I believe it to be a bolt flaw non related to anything else! I have rescued a few of these from the road side over the years You should be fine!

[Mack Snow Fighter]

Cam roller looks good, so I will put it back together with new bolts and o rings.  And other quick question, On my older truck with an EM7 engine, I did a cam job recently. I didn't have the correct tool/feeler gauge to adjust the jake brake, so for now I just left the jake disconnected.  Would it hurt anything to run the jake?  I don't want to damage anything. Thank you for your quick response, I really appreciate it! 

[fjh]

On my older truck with an EM7 engine? HP? Jake or dynatard? I don't advise using it till its set! 15 thou feeler shouldn't be hard to come by? If its a newer style  jake! your valve set is 16 /24! If its the old yoke style 400 Hp its the special tool 85 thou i Beleive! that u need the tool for there were two diffrent settings for that  don't remember the settings 80 and 85 depending on HP Joey May remember He may chime in soon! Getting old and don't precisely remember!

[Mack Snow Fighter]

It is a jake, so the slave piston setting is 15 thousands, and just a regular feeler guage gage will do? 

[Mack Snow Fighter]

Engine is EM7-300 with jake brake. 

[Joey Mack]

what year is the engine? is the jake head a 680 or 690?  I have books with specs for the 680..  I know the 690 off the top of my head..  

[Mack Snow Fighter]

Its a 1995 engine, I think the Jake adjustment might be on the valve cover, I don't know what jake, I suppose I would need to pull valve cover to tell? 

[Joey Mack]

I forgot to comment on the unit pump.. fjh is right,,  I suggest you get 12 new bolts.  8mm allen headed, 10mmx1.50,  grade 10.9,,,  70mm long I believe,  Mack should still stock them.  yoou can replace the bolts one at a time so that you wont disturb the E.U.P. o-rings. final torque is 60 ftlb's

[Joey Mack]

ok 1995,,,   680 jake heads, yes there should be a spec on valve cover.  I am trying to post the jake brake specs, but this damn #200 code keeps popping up.  My mack book says: .080''

[fjh]

22 hours ago, Joey Mack said:

ok 1995,,,   680 jake heads, yes there should be a spec on valve cover.  I am trying to post the jake brake specs, but this damn #200 code keeps popping up.  My mack book says: .080''

Thanx Joey! I don't like putting out miss info if I can help it!

[Joey Mack]

all good buddy..  The 2 of us work well together here...  

[fjh]

42 minutes ago, Joey Mack said:

all good buddy..  The 2 of us work well together here...  

🙏

[Joey Mack]

now we just need an update..  I hope He got lucky with the E.U.P.'s..  

[terry]

1 hour ago, Joey Mack said:

now we just need an update..  I hope He got lucky with the E.U.P.'s..  

yeah nice to know how any tips worked out !  Terry

[fjh]

7 hours ago, Joey Mack said:

now we just need an update..  I hope He got lucky with the E.U.P.'s..  

👍

[Mack Snow Fighter]

Got the E.U.P. back on and truck is running fine.  Ordered 10 more bolts to do the rest. Correction:  The engine is an AMI-335. 

 Going to send the truck to the dealer to delete the  idle  auto shut down, and they think they might be able to give it more power via flashing the computer. I read completely through the post on how to get more power from these engines. Thought I might as well start with the computer. We have hills here in Maine and seem to never have enough power when plowing snow.  We usually run a 6 wheel truck, same engine, on the steeper hills, because it has less dead weight. My 96 mack with the EM7-300 has more guts than the AMI ! 

 I think I know  what I need for the turbo, 5 in. exhaust, and injectors, only thing I'm not sure on is the manifold. Will an exhaust manifold from an e7 engine fit?   You guys have been awesome.  Thanks a lot for the help. 

[Joey Mack]

all good news.. 

take the exh. maniifolf off the AMI,  and replace it with the E-7 manifold, those breathe better,  you can see the differnce in diameter, and when you seperate them the AMI has an oval port that is small in comparison..   

[Joey Mack]

the ASET-AI,  would be a great engine if they would just turn the clock back and Make it an E-Tech...    

Save the manifold...  the good ones are scarce.. 

[Mack Snow Fighter]

Thank you, can't wait to try it! 

[fjh]

13 hours ago, Mack Snow Fighter said:

Got the E.U.P. back on and truck is running fine.  Ordered 10 more bolts to do the rest. Correction:  The engine is an AMI-335. 

 Going to send the truck to the dealer to delete the  idle  auto shut down, and they think they might be able to give it more power via flashing the computer. I read completely through the post on how to get more power from these engines. Thought I might as well start with the computer. We have hills here in Maine and seem to never have enough power when plowing snow.  We usually run a 6 wheel truck, same engine, on the steeper hills, because it has less dead weight. My 96 mack with the EM7-300 has more guts than the AMI ! 

 I think I know  what I need for the turbo, 5 in. exhaust, and injectors, only thing I'm not sure on is the manifold. Will an exhaust manifold from an e7 engine fit?   You guys have been awesome.  Thanks a lot for the help. 

Yup thanks for posting the fix! Bro