saving4one

windhund, thanks for the clarification, I thought that was kind of light for head bolts. Slowcrash, I was thinking of taking it to the machine shop if for nothing else than to de-carbonize the head and valves.

ATLRoAcH

I have an F24 stroker engine with 2000 miles on it built by Inlinepro. Bottom end sleeved and fully rebuilt stage 1 head rebuild and new gaskets and everything. I started getting misfire codes. I got P0300, P0302 and P0303. Just those 3 codes. The car drove fine but I could tell it had a slight misfire at idle sometimes on the last day I drove it.

The other day I started to try to diagnose it. I pulled the plugs and did a compression test and got nearly perfect results. All cylinders were between 205 and 210 PSI. The low PSI is attributed to the 9.0:1 compression pistons I have. There's little variance which is most important. My plugs also looked good. After I got done putting everything back I cleared the code and started the engine up and let it idle to charge the small PC680 battery I have back up. The car had a little misfire until it warmed up some but no code.

So the other day I go to start the car after putting some sea foam(was thinking bad gas or dirty injectors or something) in my tank to see if I could get the code to pop up again on a drive(swapped plugs and coils around to see if codes would change) and now the car won't start. I have fuel pressure because I can hear my loud Walbro and I can see fuel pressure hitting the rail on the fuel pressure gauge while the pump is running. I bought new coils packs but I haven't received them to try them out yet(will update if it fixes it). My engine has 2000 miles on it but most of everything else has 140K miles on it.

Anybody have an ideas about what my problem could be? Whatever was causing the misfire has to be what's causing it not to start now.

saving4one

I dropped my head off at the machine shop last Thursday, with instructions to disassemble measure and replace anything that needs it, and I asked that the head not be milled. I told the machinist what I had found through compression and leak-down tests, and that the #1 cyl. ex. valves were burnt. I did not take any pictures (why?) but I could not see anything visually wrong with the #1 ex. valve faces, so I'm leaving it up to the machine shop to find out the exact culprit(s). The machinist asked if I just wanted the #1 ex. valves checked and replaced if necessary, but I asked him to do them all, figuring I might as well have them all checked while the head is out. Hopefully it will be finished sometime this week, I will update when I get more info.

saving4one

Is this clean enough to put the head back on? All smooth to the touch but with some gasket staining? or something. Sorry cell pic.

Slowcrash_101

Looks good, use a lint free microfiber towel and clean with rubbing alcohol if you really want to be anal about it. The head gasket will fill in any micro imperfections. Make sure you use the correct amount of gasket maker in the correct places. Did you inspect your head bolts? If any of the upper 2" of the threads are thinner than 11.5mm you'll need new ones. It's not likely but it's good to check just in case, plus it'll give you something to do while you wait for the head repair.

By the way what was the damage to the head? Did they have to replace anything or did they just re-cut the valves?

saving4one

I cleaned and inspected my head bolts, nothing less than 11.8mm. No word from the machine shop yet, I've called, but they haven't started it, very busy there and I told them I wasn't in a big hurry. Of course I said that when I thought their regular turnaround was 3 days. This Thursday will make it 3 weeks since I dropped it off. So for now I'm just cleaning valve train parts, the block deck, bagging and labeling. I still have almost a whole can of the gasket maker listed in the shop manual that I bought to use on the block plug from my 10 year interval coolant change. Never expected to be using it again so soon!

Slowcrash_101

Normal Lucas oil stabilizer is a great assembly lube, useless as an additive but it sticks to metal so it's good at keeping stuff lubed and rust free.

saving4one

Just got off the phone with the machine shop. Only one ex. valve seat on #1 cyl. needs to be re-cut. Valve might not need to be replaced. They have disassembled everything, will lap all valves and clean everything up and install all new valve stem seals. I will know more after I pick it up, I'm at work right now.

Slowcrash_101

Cool, I figured the damage wasn't bad, still sucks you had to go though all that for one valve seat. The valve seat needs a 4 angle cut, I hope the machine shop knows this.

saving4one

I called the machine shop yesterday to find out what was up with my head, only to be informed that I should have them replace all of my exhaust valve guides! After more investigation (I thought they had already completed their assessment of the damage) they found that #1 guide was shot along with it's egg shaped seat, and several other exhaust guides are messed up also. I drove the 50 miles to the shop to see for myself and talk face to face with the shop owner about my options. I'm going with all new exhaust guides and seals (this means a full "valve job")but I don't need to replace any valves. Any thoughts?