Starting Issues (Timing? AEM CAL file issues?)

[Lowell Foo]

Scored cam bearings on a brand new build sounds like the wrong caps were installed on the head.  Even a bent cam won't cause enough drag to skip the timing belt.

[Ryan Coft]

I think your right Lowell, they don't look right to be honest, the gaps on the side don't match up. Unfortunately I didn't verify the caps when I bought the head (core).

If the caps don't fit properly, ie: they are from another head because they don't line up, the head is pretty much hooped eh? Not something that can be machines.

[John Hartman]

I have a bare, clean, pressure checked G6 head that I have started to port.  It needs guides and your hardware, but its a head that has matching caps on it.  You are welcome to have it for what I have in it money wize should you need it.  I didn't have time for that one, so I just built the head off'n my Talon, and its done.

[Ryan Coft]

I have a bare, clean, pressure checked G6 head that I have started to port.  It needs guides and your hardware, but its a head that has matching caps on it.  You are welcome to have it for what I have in it money wize should you need it.  I didn't have time for that one, so I just built the head off'n my Talon, and its done.

If this one doesn't work out I may take you up on that.

[Mike Schmid]

I've come across bent cams before that screwed me in a similar fashion. Now before I reassemble the head with lifters I install the cams and torque the caps then spin them to ensure everythings rotating smoothly

I started second guessing myself when I put my motor together on whether or not I got the caps back in the right orientation and order so I did the same because it was apart for so long.  For future reference they do spin real easy and smooth with no lifters in. 

Bummer though.  Might be able to line hone it back into shape or something but I don't know how much material you can remove before you need to put some back and I also don't know if there's any bearings available to fix that if you need that.  That's one area an old V8 is nicer than these, at least if you wipe out a cam you can put in new bearings and you don't wreck the casting. 

[Jason Gilbert]

I'm glad you found it Ryan. The worst part is not knowing!

[Ryan Coft]

So the Damage is:  1 set of bent, brand new Ferrea SS valves and dings on my pistons. Not to mention the cam which was ground to hell and the cam channel and cap that were ground up. Good news is the cam polished out and the head is at the machine shop, should be getting fixed, provided they don't find any other problems.

Here's the pictures of the pistons, iphone camera isn't that great...









So i'll have the head back tommorow or next week, seeing as i can't find an intake set of Ferrea valves I decided to just upgrade to 1mm oversized Nitrided valves. Valves should be getting seated early next week and hopefully should have it back by next weekend to go back together. It's no big deal, just throw more money and better parts at it, right?

[John Hartman]

just gonna clean up the divots in the pistons? I would.

[Matt Mann]

just gonna clean up the divots in the pistons? I would.

When I bent some valves *cough* twice   all I did was took a dremel and flatten/grinded off any protruding metal bits. No issues after that was done


PS Nice shiny pitons you have lol

[Brett Haviland]

So did the shop/guy that did the machining/building own up to being at fault?

Or is it your fault for not having the right caps to start with?  Hopefully you dont have to pay for all this out of your own pocket.  Either way it sucks ass to have a blown engine and not even see it run.

Did you do the assembly of the engine?  If not whoever did should have noticed the cam caps did not match up properly and that the cam was seizing before he sent it off to you as complete.

Good luck on getting it all back together working properly again!

[Ryan Coft]

So, after the first machine shop not being able to figure out what's wrong, they sent it to heads unlimited for repair, who also can't figure out whats wrong. Worse is that the head isn't repairable, heads unlimited won't even touch it.

Worser (not english i know, but roll with it) is that the intake cam was also scored just as bad as the exhaust side. I didn't notice because i didnt bother to pull it out after i took the exhaust cam out. Both shops say it's the head that's the problem, but don't know why. Cam caps are correctly done, cams don't appear to be bent, and i spun both cams in the head myself before i put the motor together, so i know they were spinning fine.

I'm quite confused at this point, but it's clear i'll need a new head. Which means all the port work has to be done again, valve seating, need new seals and valves. I've got valves on the way, hopefully here today.

To say i'm confused, worried and annoyed would be an accurate statement.

[John Hartman]

ballsack suckage to be sure 

Can the cams be saved?

[Ryan Coft]

Looks like it, cross my fingers

[Ryan Lore]

Wait, you never said you had spun the cams when you assembled the head.

Tell me you bled down the lifters so they were all compressed before you bolted the cam caps down.

Lifters at full extension could cause piston contact and the timing belt to skip. As for the scored cams maybe that happened after everything bent up?

[Ryan Coft]

I did spin them, with the machine shop guy.

I did bleed the lifters, i remember you telling me that many moons ago, but the more i think about it, the more i think i didn't bleed them properly. I think i bled fluid out, but possibly not the air, i don't remember (this WAS a year ago) compressing the lifters, I just remember hitting the internal valve. Maybe i didn't bleed them properly, would explain why the cams are ground down on the cam caps, the lifters weren't letting the cam lobe depress the lifter i suppose?