Anonymous

So back in the summer you guys were great help with me diagnosing my E7 for low hp after overhaul. I have 1990 E7-400 that had a series of issues after the rebuild. I got most of the kinks worked out and the biggest problem I found was that someone had installed the incorrect rack plug and the pump couldn't get full fuel. Truck is running pretty good now but I can't help but wonder if someone possibly could have put the wrong fuel plate in the pump too. the numbers on mine are 2 372 on the top and 2 071 on the bottom.

Back at it!! So after some use with the new turbo I still fell like I'm short on power. For reference I hooked my lowboy to a friends freight liner with a wore out M11 in it and it ran much better than my truck. I have decided to send the pump back to the pump shop. So I pulled it off this morning and noticed the rack plug is stamped 2000. And from my younger days we used to take the "Mack rack plug" stamped 2095 and put them in our dodges so the pumps would go full rack. My question is did Mack use any other rack plugs other than the 2095 plug? I did talk to the previous owner of the truck and he had the pump rebuilt at some point and said it never ran as good as it did before they had it rebuilt. Im wondering if someone put the wrong plug back in the pump.

That was the trick!! Now if we weren't in a drought I would be able to use them lol.

Can anyone guide me on replacing the wiper pivots on my CH613? I can't really tell how to get at them.

What a difference a new turbo makes. Got 25psi boost just driving not hooked to anything. Going to tweak the pump a little and try and get a little more out of it.

I feel like an idiot for it catching it earlier. And I also thought it should be smoking more. Guess it was getting just enough air to keep smoke down. Now I have to try and get the pump set back to where it was when I started. Will give a full report all is done. Thanks for all the help.

Well curiosity got the best of me this morning. I decided to take one more look at the turbo before I send the pump off. I removed it this time and really wanted to get a better look at the exhaust side. At first glance everything looked fine. But as I was on a phone call I was fidgeting spinning the compressor side when I noticed it had a drag for a split second then it released and spun freely. Kept on messing with it and it kept doing the same thing. I put some shop air to the exhaust side and it didn’t spin as free as it should. Would come to a stop as if it had a break applied to it. Then I removed the exhaust housing and found the carnage. New turbo should be here later this week.

Had some time to tinker today. Here's what all I did. Loosened the afc all the way up. No difference. Tightened the "smoke screw" all the way in to push the afc to wide open and kinda bypass the afc was my thinking. No difference. Even pulled the pipe off the muffler elbow to make sure it wasn't plugged up somehow. No difference. Double checked the turbo for shaft play and to see if it had any oil in it only to find it clean and free of play. Guess I will make sure the timing is correct and if so I believe I need to send the pump back off and have it rechecked.

Are you talking about the star wheel or what some people call the “smoke screw” on the backside? I have the star wheel set pretty lightly but the I found the smoke screw was backed all the way out. I turned it in and started driving and adjusting until I ran out of time l. Seemed to have a little improvement.

Not much.

Got the afc rubber replaced, shimmed the fuel return spring, slid the fuel plate just a smidge (its maybe at the half way point, drained the fuel tank and found a washer in the tank, replaced fuel line from tank to filter housing and found that the air compressor intake line had a small leak and replaced it also. Now we have 30psi fuel pressure and no boost leaks. Moved my excavator this evening and the truck runs much better but still not where I believe it should be. Could only get maybe 20psi boost pulling a hill. Has no low end power. Will spool quickly if it at higher rpm tho. going to get a guy I know that is pretty good with the Bosch pumps to come look at it and make sure I'm not missing something or doing something wrong.

I pulled the housing off. It moved freely with shop air but I just felt like something was still wrong so I pulled it all the way down. There’s actually two cuts in it. I think I can find one at my dads. I’ll let y’all know how it goes once I get it sorted.

Found this today hoping it’s going to fix it

No mine doesn’t have that.

I did check the afc for by sucking and blowing into it. I’m going to pull it off and check it out and make sure that it’s working properly. And not set for too high of boost to get full rack. If all that checks out I’m going to recheck timing.