One problem after the next

[JNM240]

So i drove my CA coupe from New Orleans are to Athens, Ga for Christmas, about an 8 hour drive each way. No problem. A week later, i notice an exhaust noise from the engine bay: the tubular exhaust manifold had lost a weld. Great. Ordered a new one ($89 off eBay), put that on, drove it around the block (ran great!) and as i pull back into the driveway, she dies and wont start back up. Just keeps cranking and cranking.

Turns out the keyway that hold the crank timing belt sprocket sheared sideways, allowing the sprocket to move roughly 2 teeth in either direction.

So now ive a new tensioner, idler, Greddy Extreme belt, keyway and sprocket on the way. Hopefully by the end of the week, she'll be running like new again!!

[sjbsuperman1425]

its always good to vent lol. Im in the same situation kind of, the head is off my engine and I have to wait another month or so to bring the car home from storage to work on it and get it running, hoping the hot tank didn't destroy my valve seals. Its terrible!

btw, what was the original manifold and who is the new one from?

[JNM240]

They we both just those cheap bottom mount manifolds off of ebay. This is actually my FOURTH manifold, but i replaced the first 2 while changing turbos out because i broke a stud off and didnt feel like it was worth it to drill and tap it out, just spend another $89 and get a new one. This is the first one that actually came apart on me.

[float_6969]

Wow, I've never heard of anybody shearing the keyway on a CA18. Are you sure you don't have a problem somewhere else?

[mbmbmb23]

They we both just those cheap bottom mount manifolds off of ebay. This is actually my FOURTH manifold, but i replaced the first 2 while changing turbos out because i broke a stud off and didnt feel like it was worth it to drill and tap it out, just spend another $89 and get a new one. This is the first one that actually came apart on me.

Does your downpipe have a brace that hooks to the transmission mount? If not the entire weight of the exhaust is bouncing up and down on those welds when you hit a pothole. Just curious cause I will be using one of those manifolds (with DP support).

-m

[bentvalves]

yea a properly hung exhaust with a transmission brace on the downpipe, and a catback that isnt hitting the ground, or bouncing around is a solid idea. Even Tomei and HKS stainless manifolds crack, and HKS cost roughly 13 times as much as an xspower

[JNM240]

Wow, I've never heard of anybody shearing the keyway on a CA18. Are you sure you don't have a problem somewhere else?

It didnt completely shear, just mal-deform it sideways a bit. Talking to two of the techs i work with, they say that if i didnt tighten the crank pulley bolt down enough, that could cause this problem. They also said i should feel lucky the crank wasnt damaged.

Does your downpipe have a brace that hooks to the transmission mount? If not the entire weight of the exhaust is bouncing up and down on those welds when you hit a pothole. Just curious cause I will be using one of those manifolds (with DP support).

-m

Yup, i have a Meagan downpipe with the brace attached to the transmission mount, and my HKS exhaust is mounted at all the factory locations. I would like to get some stiffer engine mounts (transmission mount is a Nismo). Im pretty sure the welds came off due to cruising 8 hours a time at 15:1 AFRs with an EGT (read just behind the turbo) of around 1400 degrees. That and crappy welds, because the steel didnt crack.

Jason