tick, tick, tick......

Jff24Gordn

Jff24Gordn

FIRE
Joined
Jun 9, 2006
Messages
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After the last time I did a speed exhibition of going 4x the speed limit, I noticed a tick in the motor. I fixed it with the radio volume knob.
That didnt work, so I popped off the valve covers to see if anything looked odd. Well #1 exhaust rocker broke the snap ring, and the rocker moved as far sideways as it could till the pushrod was in the head. At least the rocker was still just touching the valve when it pushed down. There is 0.006" or so missing off of the pushrod, and just enough of a scuff to see on the inside of the rocker and the shaft. The snap ring halves were still on the head. The thrust washer was there, too.
Anybody ever break one of these before, because I cant recall hearing about it.
 

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I've seen the pushrod cup separate from the pushrod on the dmax before, but nothing like that on the cummins. I would guess valve float caused the failure?

brandon.
 
Jff24Gordn said:
After the last time I did a speed exhibition of going 4x the speed limit, I noticed a tick in the motor. I fixed it with the radio volume knob.
That didnt work, so I popped off the valve covers to see if anything looked odd. Well #1 exhaust rocker broke the snap ring, and the rocker moved as far sideways as it could till the pushrod was in the head. At least the rocker was still just touching the valve when it pushed down. There is 0.006" or so missing off of the pushrod, and just enough of a scuff to see on the inside of the rocker and the shaft. The snap ring halves were still on the head. The thrust washer was there, too.
Anybody ever break one of these before, because I cant recall hearing about it.
Click to expand...

I like your tick, tick, tick WAAAYYYYY more than the one I found. Good save though.
 
Timbeaux38 said:
What did you find man?
Click to expand...

A lump of metal resembling a piston? :hehe:

Seriously, I don't know exactly "for sure" what happened. I've got it straightened out and as soon as I get a new piston all should be good. I pulled up some vids I took of it when I first got it and I could hear the tick in it then. So it was the prior owner who should have the answer. It was a 1 owner truck when I bought it. I gave him a call, but he wasn't admitting anything. Stuck injector? It's where I leaning towards. But honestly, I don't know... I'll just make sure when I put her back together, everything is right.

Mr. Jff24Gordn, I'm siding with Joe on this, I think you had some valve float, taking a look at your valve springs, are those the 60lbs springs? Those sure look little to me, I see you have a 4GSK installed, if you didn't get the springs, now's the time.
 
Well, the box had a PDR part number on it. Gov and valve springs. If anybody has their valve covers off, whats the diameter of a 60# spring.
I'm sure I floated the valves, I was just surprised I broke a snapring instead of bent a pushrod.
 
If no one else has, I'll check the diameter once I get home tonight.

brnadon.
 
joefarmer said:
If no one else has, I'll check the diameter once I get home tonight.

brnadon.
Click to expand...

I would, but my head is still being worked so no measuring for me...
 
Outside diameter appears to be 1.445". My battery was low on the caliper so I'm only half sure if that's right.

brandon.
 
Thats the same OD of the spring I have, whats the diameter of the wire its self? I have around 0.19 or so, I cant get the jaws of my caliper in there to measure it.
 
THe OD of the stock is visibly less, I'd say in the 1.2-1.3 range. Here's a picture:
spring_xy.jpg


brandon.
 
I went through and changed all of the snap rings and thrust washers. Most of them were just fine, but there was one that was loose on the shaft.
 
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