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TrojanMan
11-25-2005, 08:14 PM
So the stroker started making a noise after dad drove it without turning the cooling fan on. It's a clanking noise almost like if there was no piston on the rod and it's slapping around inside the cylinder. When you put it in gear it becomes more of a tapping/clicking noise. When you drive the sound varies with rpm, not speed. The funny thing is if I shifted to N (while driving) and gave it some throttle, the noise would temporarily go away. First I suspected lifter problems.. so I pulled the valve cover and checked. No play in the lifters at all. All bolts are tight. I then pull the oil (http://jeepsunlimited.com/forums/showthread.php?p=6005604#) pan to check out bearings. I isolated the noise to the back of the engine (http://jeepsunlimited.com/forums/showthread.php?p=6005604#) using a stethloscope. I pulled the number 6 rod cap and number 6 main cap, pictured below. What do you guys think about the wear pattern? When I rotated the crank around after the number 6 rod cap was removed (to get access to the number 5) it made the noise again, I couldn't tell if it was coming from the number 6 rod or not. It almost sounded like it was coming from the transmission. I'd like to think it isn't the torque converter (http://jeepsunlimited.com/forums/showthread.php?p=6005604#), it's a level 10 heavy duty converter with only 5K miles on it, give or take. I'm kind of leaning towards that being the problem, though, because this is the same noise the engine made back in april when I decided to scrap the 4.0 and stroke it. What do you guys think?

The scars in the rod bearing near the top are noticable by the fingernail.

http://www4.ncsu.edu/~djross/bearings.bmp

rob92xj
11-26-2005, 09:20 AM
T-man check your torque converter bolts, they often come loose. If they are loose use locktite on them when you retighten them. If they are tight look for cracks on your flexplate. The bearings look like normal break-in wear.

TrojanMan
11-26-2005, 08:26 PM
Pretty sure it was the torque converter bolts. They were loose enough to pull out by hand. Also, there was an indention in the flex plate where the bolts were hitting.. as well as very damaged threads on the top portion of the bolt where it hit the flex plate. Can anybody verify the pattern of the welded nut on the torque converter? I bought m8 1.00 pitch because that seemed to be the right fit, however it was a little tough to tell because only 1/4" of the thread was good enough to test fit. Had to cut the bolts I bought to length to fit right, i'm putting a lock washer and lock tite on them this time. Before I bolt these in and possibly damage threads or any other mistake - is m8 1.00 pitch the right thread and is there enough room in the access cover to put a lock washer on? Thanks for everything so far fellas.

rob92xj
11-26-2005, 08:59 PM
I'm not sure of the right size off the top of my head but I think it may be a standard size and not metric, as the original bolts are the same bolts used by Chrysler since the very first Torque Flight transmissions. Also the bolts are hardened bolts. I can look around at work to see if I can find you a set. I could try and drop them off in Charlotte next week while I'm at class.

TrojanMan
11-26-2005, 11:34 PM
If you could, i'd really appreciate it. Only trouble is.. i'm heading back to raleigh for school late tomorrow afternoon. You could stick them in an envelope and drop them in my mailbox if you like - my parents could bring it in with the mail. I guess if they're hardened the bolts I got wouldn't be as favorable - especially considering i'm cutting them down. If you don't have any let me know and I guess i'll bite the bullet and buy some. Give me a call and let me know. Thanks alot man, if there is ever anything I can do for you, let me know.

by the way, how do you feel about using grey RTV instead of a gasket for the valve cover? I accidentally tore the cork one and I don't feel like paying 50 bucks for a new one.