ArdWrknTrk Posted July 31, 2019 Share Posted July 31, 2019 But, it may not be as bad as you think. I agree Gary. Also note that he rotated the crank CCW first until all the slack came out, and then rotated the crank CW. Even if everything is fine, there'd be a lot of slack to switch from CCW to CW. When I took my 302 apart, the factory chain was really loose, and that was with only 30k miles on it. Might be hard to tell in the picture below, but that chain was really loose. Ugh Plastic.... Link to comment Share on other sites More sharing options...
reamer Posted July 31, 2019 Author Share Posted July 31, 2019 Ugh Plastic.... So I did the test again, this time I cleaned off the harmonic balancer timing marks, rotated the crank Counterclockwise two complete rotations to ensure the rotor was under tension, then stopped rotating the crank with the pointer at the mark of 30 degrees BTDC. Then rotated with a breaker bar clockwise until the rotor just started to move, and looked at the harmonic balancer, it is now at 10 degrees BTDC. This took out any play in the breaker bar. So I have 20 degrees O' play. Enough for surgery? Always said to myself, if it needs repair, pull it and do a complete rebuild... But with 150 psi per cylinder, AND dealing with the falling apart cement foundation, I think just do a chain, front oil pan seal, water pump... Thoughts? Link to comment Share on other sites More sharing options...
Gary Lewis Posted July 31, 2019 Share Posted July 31, 2019 So I did the test again, this time I cleaned off the harmonic balancer timing marks, rotated the crank Counterclockwise two complete rotations to ensure the rotor was under tension, then stopped rotating the crank with the pointer at the mark of 30 degrees BTDC. Then rotated with a breaker bar clockwise until the rotor just started to move, and looked at the harmonic balancer, it is now at 10 degrees BTDC. This took out any play in the breaker bar. So I have 20 degrees O' play. Enough for surgery? Always said to myself, if it needs repair, pull it and do a complete rebuild... But with 150 psi per cylinder, AND dealing with the falling apart cement foundation, I think just do a chain, front oil pan seal, water pump... Thoughts? Yes, that's a problem. And yes, I'd do the "chain, front oil pan seal, water pump..." Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 31, 2019 Share Posted July 31, 2019 Yes, that's a problem. And yes, I'd do the "chain, front oil pan seal, water pump..." "front main seal" and a speedisleeve. The timing gasket set WITH is only $6 more (in my case) and I'd rather be looking at it than looking for it.... Link to comment Share on other sites More sharing options...
reamer Posted August 1, 2019 Author Share Posted August 1, 2019 "front main seal" and a speedisleeve. The timing gasket set WITH is only $6 more (in my case) and I'd rather be looking at it than looking for it.... Thinking of going with Jasper crate engine, the "Stock Performance Model." seems this would be a faster-cleaner way, and I may pull the ZF-42 for a rebuild too, The ZF shifts fine, stays in gear, (even in reverse) but a Idle is sounds like massive rod-knock, (push clutch in and all is quiet), and a crap load of chatter in the sweet spot between acceleration-load and deceleration-load.. Thoughts? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted August 1, 2019 Share Posted August 1, 2019 Thinking of going with Jasper crate engine, the "Stock Performance Model." seems this would be a faster-cleaner way, and I may pull the ZF-42 for a rebuild too, The ZF shifts fine, stays in gear, (even in reverse) but a Idle is sounds like massive rod-knock, (push clutch in and all is quiet), and a crap load of chatter in the sweet spot between acceleration-load and deceleration-load.. Thoughts? I think your engine has good compression and more miles to go before it's clapped out. Timing chains are a wear item, and need changing. I think all Zf's clatter at idle in neutral. "Rollover" is always there unless you run it over full or really heavy gear oil (which is no good for the synchro's) Knocking when lugging is excessive end play, and the helical gears banging the shaft into the thrust bearing. Not the end of the world. My truck has been doing it since I swapped the Zf in. All will do this. It's a matter of how loud. You have a truck gearbox.... In a truck. That's the way it's going to behave. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 1, 2019 Share Posted August 1, 2019 I think your engine has good compression and more miles to go before it's clapped out. Timing chains are a wear item, and need changing. I think all Zf's clatter at idle in neutral. "Rollover" is always there unless you run it over full or really heavy gear oil (which is no good for the synchro's) Knocking when lugging is excessive end play, and the helical gears banging the shaft into the thrust bearing. Not the end of the world. My truck has been doing it since I swapped the Zf in. All will do this. It's a matter of how loud. You have a truck gearbox.... In a truck. That's the way it's going to behave. I agree. A ZF5 is a noisy tranny. Mine worked pretty well with bad synchros and a broken reverse gear, which just meant that shifting had to be done slowly and there were times it would NOT go into Reverse w/o moving the truck forward. But a rebuild is expensive. I paid a pro ~$1000 for a complete rebuild on mine, inc parts. But he was moonlighting and using the shop's facilities, so I got a good deal. IOW, it would have been more had it been done "professionally". However, I would have then had a warranty, so I'm not sure which way would have been better. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted August 1, 2019 Share Posted August 1, 2019 I agree. A ZF5 is a noisy tranny. Mine worked pretty well with bad synchros and a broken reverse gear, which just meant that shifting had to be done slowly and there were times it would NOT go into Reverse w/o moving the truck forward. But a rebuild is expensive. I paid a pro ~$1000 for a complete rebuild on mine, inc parts. But he was moonlighting and using the shop's facilities, so I got a good deal. IOW, it would have been more had it been done "professionally". However, I would have then had a warranty, so I'm not sure which way would have been better. 9/10 not going into reverse is a clutch drag issue. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 1, 2019 Share Posted August 1, 2019 9/10 not going into reverse is a clutch drag issue. Yes, but this was the 1 out of 10. It wouldn't only do it every once in a while, and then it would NOT go w/o moving the truck. So I learned to never, ever park where you couldn't roll forward. Then when the guy took it apart he discovered the reverse gear was broken. According to him that would create those symptoms. Link to comment Share on other sites More sharing options...
reamer Posted August 1, 2019 Author Share Posted August 1, 2019 Yes, but this was the 1 out of 10. It wouldn't only do it every once in a while, and then it would NOT go w/o moving the truck. So I learned to never, ever park where you couldn't roll forward. Then when the guy took it apart he discovered the reverse gear was broken. According to him that would create those symptoms. The chattering with no load at highway speeds is Normal? Link to comment Share on other sites More sharing options...
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