1G Accidental Downshift. Oops.

[thejollyrancher]

(I'm posting this in the Newbie forum because I'm not sure where else it should go.)

Time to vent!

While fixing up my tune today I had the good old Talon going in third. Right at red-line I go to shift to fourth but of course I miss and pop it into second . I lunge towards my windshield and hear two loud BANG!s that seem to come from behind me. Next thing you know shes dead and I'm trying to roll home. I can crank the engine smoothly but it wont turn over. Sounds like bent valves to me so I'm going to check compression and timing tomorrow morning, might drop the oil pan as well.

Thoughts? Suggestions?

 

[mtf-DSM]

Hello... I'm no engine expert at all but in my opinion it may have caused the valves to float which could have a bad effect on your seats, and if severe enough, may even cause them to contact with the pistons which would bend them... And then that could have caused the two "bangs" due to severe misfiring. Definitely a smart place to start is the head, but never rule out spun bearings in the bottom. Hope this helps and good luck

 

[miliman13]

You described in detail the same situation I had once. Head will have to come off. Most likely require full over haul. Your block should be fine, but doesn't hurt to try and diagnose it, don't bother testing valves you know it has to come off. At least it was you, it happens to me when a dummy drove my car the 1st week I had it.- good luck.

 

[Talyn]

I would check the timing, belt and tension before I started tearing things apart.

 

[dennington95gst]

Sounds like bent valves to me. I would definitely to a compressions test before tearing into it.

 

[thejollyrancher]

Thanks for te replies guys. Ill check compression and timing today. Ill keep you updated!

 

[thejollyrancher]

Did a compression test and 0 compression in cylinder 2! The rest were well below 130 as well. Time for a rebuild!

 

[dennington95gst]

That sucks man! At least you know now. Time to build bigger and badder

 

[mtf-DSM]

Sorry about that, dude... But at least it happened early enough to still have it back on the road for the summer when the car scene is really wide open. Good luck on the rebuild.

 

[thejollyrancher]

Thanks guys! Its about time for a rebuild anyways. Perfect time to do a timing job, meth, and a holset for the summer !

 

[jimsgsx]

Man you must hate yourself. Not being disrespectful but i know how that feels.

 

[yhype]

Could just make a nice weekend job and put new valves in cyl #2 so you have the car back up and running....instead of turning one problem a lenghthy build which doesn't pan out like has happened to way to many DSMs over the years. Just my .02 anyways...Good luck with your car.

 

[SrKegler]

He's kind of like me. When I have the car apart, I fix everything it needs at one time. Especially when you already have the head off, might as well freshen up the bottom end, replace all the seals, timing components, water pump. That way you know you're good to go for another 60k.

 

[thejollyrancher]

Ya I do feel pretty shitty about it, but going forward I'll be a lot more careful with my shifting.

Could just make a nice weekend job and put new valves in cyl #2 so you have the car back up and running....instead of turning one problem a lenghthy build which doesn't pan out like has happened to way to many DSMs over the years. Just my .02 anyways...Good luck with your car.

I agree. But I already have the timing belt kit waiting to go in, I have a meth kit, and I have the holset waiting to go on too. Plus I have new valves and pistons waiting to go in... So Im pretty well prepared! Wouldnt make sense for me not to just do a whole rebuild at this point.

 

[HIGHPSI4]

With the other cylinders below 130 psi you don't just want to put valves in cylinder 2.

 

[thejollyrancher]

With the other cylinders below 130 psi you don't just want to put valves in cylinder 2.

Yup ill be swapping them all

 

[Talyn]

I actually did the same thing once, and immediately popped the clutch when it went into 2nd...I got lucky though, I'm extra careful going for 4th now...Best of luck with the rebuild, if you plan on stock valves I think I might still have mine from my build.

 

[thejollyrancher]

I actually did the same thing once, and immediately popped the clutch when it went into 2nd...I got lucky though, I'm extra careful going for 4th now...Best of luck with the rebuild, if you plan on stock valves I think I might still have mine from my build.

Thanks Talyn ! I'm glad your car survived, I'll be super careful now. Ill PM you if I end up needing some valves. I have a built engine someone was selling pretty cheap so hopefully there's some goodies inside. If those arent useable, youll hear from me.

 

[Spanky_DSM]

One question.
How do you miss 4th!?


I'm joking haha
Shit happens. Hope she's up and running soon..... (With some new shifter bushings)

 

[DSM1G90]

With the other cylinders below 130 psi you don't just want to put valves in cylinder 2.

I'd do a bottom end with that compression pressure.

If you're going to do the top, best do the bottom along with it.

Even then, that's just a quick fix, esp if doing the bottom, since you should check the bores for straightness and roundness for the new rings and bearings.