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Thread: Jensens follow up issue thread

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Posts: 21-27 of 27
2010-07-05 19:25:39
#21
Wouldn't it be a good time to start with a fresh motor. How many times have you split this thing open? JDM DE.
2010-07-05 20:50:11
#22
I bet it skip time and thats what caused the exhaust rockers to throw as the valves contacted the pistons and bent, the valves no longer came all the way back up and threw the rockers off the next cam revolution around.

Hopefully the pistons are alright. Make sure to replace that tensioner with an updated one. As thats the only reason it would skip time to begin with.
2010-07-06 00:34:11
#23
Originally Posted by Benito
Wouldn't it be a good time to start with a fresh motor. How many times have you split this thing open? JDM DE.


The build is fresh, with the bottom end. The only thing that wasn't touched was the head. Should have just done the head when it was off. Hopefully there's no damage to the face of the piston. If they're good, then we move forward with a fresh head, after we verify nothing in the rotating assembly was damaged.

Originally Posted by ashtonsser
I bet it skip time and thats what caused the exhaust rockers to throw as the valves contacted the pistons and bent, the valves no longer came all the way back up and threw the rockers off the next cam revolution around.

Hopefully the pistons are alright. Make sure to replace that tensioner with an updated one. As thats the only reason it would skip time to begin with.


High probability that it skipped timing somehow. One thing he noticed today was that the exhaust cam gear wasn't even torqued. He could spin the cam bolt with his hand I'm thinking that there was too much movement/play with the cam gear. He will need cam gears for sure, and may have to replace his BC STG 2 cam. I think he's getting S4's though.
2010-07-06 00:47:48
#24
Yeah, that will do it thats for sure. Rockers dont just fly off for no reason like that. The only time ive had them fly off is from an over rev.

On my first se-r with a jdm motor i put in, I abused that thing like crazy and one time during a highway pull with when the newest body tiberon's came out i went from 7750 in third into second for several seconds before punching the clutch back in. Needless to say the engine died and later popped the valve cover and it was horrible. I threw every single rocker arm but 1 and all the others were shattered into bits. Lucky my s3 cams were not too dinged. I cleaned up all the pieces inside the head, got a new set of rocker arms from the dealer and took a file to the dings on the cams to smoothen them out and whalla, fired right back up and went to the track that weekend and was running the same 14.3-4 at 96-97mph. No damage done to the motor at all. Put 55k miles on that motor of absolute torture.

I hope you guys can get it all squared away with no issues after throwing a new head on there. Did the cam gear seat on the cam get all chewed up, is that why your saying he needs to replace it or is it because of dings on the lobes.
2010-07-06 01:00:20
#25
I bent valves once with over revving and once just idle. On the later it was cause I forgot to torque the cam gears. Suck to hear as I have been here. Put the head on and was gonna take my cousin for a ride before he went back to TX. Lets just say he didn't get his ride
2010-07-06 01:04:17
#26
Its something that is easy to forget too. You throw the cams in and snug the gears by hand and then rotate it over to check and make sure everything remains in time after releasing the tensioner and throw the valve cover back on and oops.

Ive done it one time to where i questioned myself if i forgot to torque the cam gear bolts so i popped the valve cover to double check. They were definetly torqued but its something you just dont want to chance. Cuz if something happens your done for.
2010-07-06 01:40:13
#27
You might want to change the head stud. Will this be #2 or 3?
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