TNBrett
Full Access Member
So, as you guys may have noticed in a couple other threads, I've pulled the engine and trans from my truck in order to address the leaking head gasket, and a few other issues. I figured I'd go over what I've done so far, talk about what I've found, And ask for some opinions on a few things.
I know there's lots of opinions on which way is easiest to remove these engines. This is how I chose to do it, turbo, and oil cooler still on, and core support removed. Also, the starter was removed. As you can also see, I unbolted the motor mounts and they stayed with the truck. I kept the engine level and basically just went up enough to let the oil pan clear the cross member. I also made sure to leave the ground strap on the back of the passenger side head attached to the firewall so I could stretch it out nice and tight.
So the primary mission is heads and studs. I had a set of heads from the original NA motor that was in my truck originally. About a month or two ago I took them to a local machine shop that had a pretty good reputation. They cleaned and inspected the heads and basically told me they were not worth the trouble. One head had been redone already, but not well. Instead of replacing the guides, the last shop reamed them out, and used valves w/ oversized stems. The guides in the other head were beyond just loose. In any event, both heads were so bad that the normal machine they use to cut out guides wouldn't work, and they would require several hours of machining on each head. They recommended a set of Reman heads from Allied cylinder head @ $350 each plus tax and shipping. So for a little over $800 I've got two heads ready to go. I managed to pick up one of the last sets of ARP studs that were available from Wes, and one of the last intake / valley pan gaskets from Napa. I also have a Fel-Pro head gasket set. My questions here are;
1) What should torque the studs to? Should I just use the factory spec? I've seen reference to 150 ft/lb.
2) What about the 6.9 cooling mod? I know a lot of you guys do it, but I wasn't having any issues cooling before. My question is, if the 6.9 design was better, why did Navistar (or maybe it was Ford) change it. what were they looking to achieve by blocking those passages? Basically I'm open to it, but I need to be sold on it a little bit.
The next big thing for me is the clutch. I've mentioned before that everything seemed normal when I would first get in the truck in the morning. The problem was that once everything got heat soaked, it was extremely "grabby" in 1st and reverse. It was a real pain trying to back up a trailer delicately. Shifting between gears was never an issue, and I never noticed any slipping or burning. Well, here's what my flywheel looks like.
There's obviously some hot spots on it. There's hot spots on the pressure plate as well, and the clutch disk is worn. The buffer springs are a little loose in it as well.
I'm going to go by the clutch shop tomorrow, and see about having the flywheel ground. I was also going to ask about having the flywheel drilled for a 13" PSD clutch. What do you guys think about that idea? Do you think the flywheel is too damaged to grind? I only see discoloration, no signs of heat cracks. The other thing I've noticed while looking at PSD clutch kits is that they all seem to have fewer buffer springs in the clutch disks that the IDI clutches do. Also on the subject of clutches, I'm planning on replacing the slave cylinder and using Russ's clutch hose. Mainly, this is because I broke the plastic retainer on my current slave cylinder and getting it back in without that is a real PITA.
Otherwise, everything else is pretty minor. I'm redoing the olives on the turbo feed line, and hard fuel lines. I'm also replacing the front and rear main seals, and I ordered new motor mounts. I may throw some spay paint at it too before I put her back in.
Oh, and one last thing. Does any one have a source for the inner shift boot for the ZF5? I found one on ebay, but it looks like the quality may not be so hot. Mine is torn and has made a minor mess.
TIA, I'm looking forward to everyone's input.
You must be registered for see images attach
I know there's lots of opinions on which way is easiest to remove these engines. This is how I chose to do it, turbo, and oil cooler still on, and core support removed. Also, the starter was removed. As you can also see, I unbolted the motor mounts and they stayed with the truck. I kept the engine level and basically just went up enough to let the oil pan clear the cross member. I also made sure to leave the ground strap on the back of the passenger side head attached to the firewall so I could stretch it out nice and tight.
You must be registered for see images attach
I figured I'd include this pic to show what I did to get the transmission out. With the front up as high as I could go on jacks, and the back tires just off the ground, I was able to sneak it out without taking it off of the transmission jack. Once I had the shifter out, I tilted the bellhousing down to clear the frame. So the primary mission is heads and studs. I had a set of heads from the original NA motor that was in my truck originally. About a month or two ago I took them to a local machine shop that had a pretty good reputation. They cleaned and inspected the heads and basically told me they were not worth the trouble. One head had been redone already, but not well. Instead of replacing the guides, the last shop reamed them out, and used valves w/ oversized stems. The guides in the other head were beyond just loose. In any event, both heads were so bad that the normal machine they use to cut out guides wouldn't work, and they would require several hours of machining on each head. They recommended a set of Reman heads from Allied cylinder head @ $350 each plus tax and shipping. So for a little over $800 I've got two heads ready to go. I managed to pick up one of the last sets of ARP studs that were available from Wes, and one of the last intake / valley pan gaskets from Napa. I also have a Fel-Pro head gasket set. My questions here are;
1) What should torque the studs to? Should I just use the factory spec? I've seen reference to 150 ft/lb.
2) What about the 6.9 cooling mod? I know a lot of you guys do it, but I wasn't having any issues cooling before. My question is, if the 6.9 design was better, why did Navistar (or maybe it was Ford) change it. what were they looking to achieve by blocking those passages? Basically I'm open to it, but I need to be sold on it a little bit.
The next big thing for me is the clutch. I've mentioned before that everything seemed normal when I would first get in the truck in the morning. The problem was that once everything got heat soaked, it was extremely "grabby" in 1st and reverse. It was a real pain trying to back up a trailer delicately. Shifting between gears was never an issue, and I never noticed any slipping or burning. Well, here's what my flywheel looks like.
You must be registered for see images attach
There's obviously some hot spots on it. There's hot spots on the pressure plate as well, and the clutch disk is worn. The buffer springs are a little loose in it as well.
You must be registered for see images attach
I'm going to go by the clutch shop tomorrow, and see about having the flywheel ground. I was also going to ask about having the flywheel drilled for a 13" PSD clutch. What do you guys think about that idea? Do you think the flywheel is too damaged to grind? I only see discoloration, no signs of heat cracks. The other thing I've noticed while looking at PSD clutch kits is that they all seem to have fewer buffer springs in the clutch disks that the IDI clutches do. Also on the subject of clutches, I'm planning on replacing the slave cylinder and using Russ's clutch hose. Mainly, this is because I broke the plastic retainer on my current slave cylinder and getting it back in without that is a real PITA.
Otherwise, everything else is pretty minor. I'm redoing the olives on the turbo feed line, and hard fuel lines. I'm also replacing the front and rear main seals, and I ordered new motor mounts. I may throw some spay paint at it too before I put her back in.
Oh, and one last thing. Does any one have a source for the inner shift boot for the ZF5? I found one on ebay, but it looks like the quality may not be so hot. Mine is torn and has made a minor mess.
TIA, I'm looking forward to everyone's input.