Bad misfire (cylinders 1 through 4), P0300
#11
I'll be pulling the valve cover off later this week to see what, precisely has happened. I'm not entirely sure what worst-case is for this, I imagine a crate motor is a few thousand bucks. Maybe a rocker arm just slipped off a stud or something, I'm not entirely sure how it looks under there.
#12
#13
How bad is "dropping a valve seat" and all that?
Last edited by keenerb; 07-28-2014 at 09:16 PM.
#14
It depends...
You'll be pulling the head. The valve seat may have cracked allowing it to come out but any overheat can do it as well.
There might be some piston damage but it may not be enough to worry about.
Replace the seat and the valve if necessary. Replace the cam follower, hopefully the cam is OK.
Take some pics if you can.
You'll be pulling the head. The valve seat may have cracked allowing it to come out but any overheat can do it as well.
There might be some piston damage but it may not be enough to worry about.
Replace the seat and the valve if necessary. Replace the cam follower, hopefully the cam is OK.
Take some pics if you can.
#15
Doesn't it always...
You'll be pulling the head. The valve seat may have cracked allowing it to come out but any overheat can do it as well.
There might be some piston damage but it may not be enough to worry about.
Replace the seat and the valve if necessary. Replace the cam follower, hopefully the cam is OK.
Take some pics if you can.
Here's the hole in the valve cover. I don't have much else to offer at the moment. I'll be removing the valve cover this evening or tomorrow evening, as time permits.
You'll be pulling the head. The valve seat may have cracked allowing it to come out but any overheat can do it as well.
There might be some piston damage but it may not be enough to worry about.
Replace the seat and the valve if necessary. Replace the cam follower, hopefully the cam is OK.
Take some pics if you can.
Last edited by keenerb; 07-29-2014 at 09:08 AM.
#17
Yeah, I'm actually not TOO worried. Even though we're expecting some downtime with the truck at this point, she's still got something to drive to work and back. I've never pulled a head, but I love working on cars, so I'm honestly looking forwards to it just a little bit.
My mechanic friend thinks it's the rocker arm, so we'll see.
My mechanic friend thinks it's the rocker arm, so we'll see.
#19
I assume you mean the radiator cap above? The thermostat sits underneath on the 4.7L. If you've replaced the cap and it still leaks at the neck, there may be a crack or wear, preventing a seal. JB weld can sometimes get you by but a replacement may be in order.
Edit... just remembered that the upper radiator hose is where the "neck" is located and not on the actual radiator. Not near my truck to see right now, but maybe you can just replace the T-junction/filler neck?
Last edited by Dodgevity; 07-29-2014 at 10:56 AM.
#20
Well, too bad it wasn't an easy fix but sounds like you'll have fun wrenching on it.
I assume you mean the radiator cap above? The thermostat sits underneath on the 4.7L. If you've replaced the cap and it still leaks at the neck, there may be a crack or wear, preventing a seal. JB weld can sometimes get you by but a replacement may be in order.
Edit... just remembered that the upper radiator hose is where the "neck" is located and not on the actual radiator. Not near my truck to see right now, but maybe you can just replace the T-junction/filler neck?
I assume you mean the radiator cap above? The thermostat sits underneath on the 4.7L. If you've replaced the cap and it still leaks at the neck, there may be a crack or wear, preventing a seal. JB weld can sometimes get you by but a replacement may be in order.
Edit... just remembered that the upper radiator hose is where the "neck" is located and not on the actual radiator. Not near my truck to see right now, but maybe you can just replace the T-junction/filler neck?