MT YOTA

Hey guys.

I thought I would share a recent 3.0 experience I have had. I bought my truck last year with a motor that was rebuilt about 40,000 miles ago. About a week and a half ago I started hearing a clicking sound in the engine. The clicking was really fairly loud starting at 3000rpm. I ran Seafoam through it in hopes it might be a sticky injector or something. No luck with the Seafoam so I decided to take it to a shop I trust knowing something was definitely wrong. When they went to pull it into the bay the sound got really loud and then it suddenly could barely run. When they dug in to investigate the problem they found that the 5th valve spring had broke in half. I'm not sure how common that is?? Shes all fixed up as good as used again. Any who I just thought someone out there may find this experience helpful in some way if their 3.0 has similar symptoms... This could be a very weird wacky deal.

-Sean-

MudHippy

That's a new one. Never heard of that happening before. Must be an extremely rare occurance.

I assume by "5th" you mean the #5 cylinder. And by "valve spring" you mean the exhaust valve spring. Are these assumptions correct?

Just curious...

MT YOTA

You are correct with those assumptions. I assume over tightening occurred during the rebuild. Which says a lot for the Toyota dealer that rebuilt the motor... On a random note, the censorship on this forum is over the top IMO. My sincere apologies to everyone for my absent mindedly "trying to bypass the censor". ? That was not my intention. Sorry.

MudHippy

I'm not sure what you mean by that. But if you mean they shimmed the valve spring(s) to increase install height tension, I highly doubt it. That's not standard practice on this engine. And, in fact, Toyota doesn't even provide the parts(valve spring shims, and/or different sized valve spring seats) necessary to accomplish it. Instead, the FSM instructs one to replace any valve springs that don't meet the install height tension specifications. No adjustment required/recommended.

So, maybe they re-installed a valve spring that they should have replaced. It's possible that they may have even checked the install height tension, found it unsatisfactory, and decided to re-install it anyway. Or perhaps they didn't even bother checking the install height tension on it/them before re-installing it/them. Or they might have done some other stupid, careless, irresponsible thing they shouldn't have to/with the valve spring(s). Who knows? But, whatever they did, it's extremely unlikely that they "overtightened"/shimmed/used thicker spring seats on any of the valve springs.

On the censorship thing...welcome to KINDERGARTENTECH!

MT YOTA

Its very possible that they did reuse a spring or all of them. I wish that I had bought it from the original owner who had the rebuild done so that I knew more of the trucks history. Thank you for your input MudHippy you are knowledgeable and helpful. Kindergartentech is spot on. lol