Cobra issues... Any thoughts?

[slow ride]

Hard to say, but even if the spring was weak it wouldn't cause a problem when cranking the engine over of a compression test I'd think. Just seems like there is a valve stem to guide issue going on. I'm guessing the head will have to come off, but I hope it doesn't. Good luck with it.

[Phish]

Yeah, we should know saturday. The valve is where we will dive to first. I will try and keep everyone posted, but this seems to be the only theory that we can come up with at the moment.

[Phish]

So, Yesterday I head to Jordans to attack this car a little more. Our plan of action before heading to the garage was to remove the head and check the valve in the valve guide along with the spring. We head to the garage and just for grins we check the compression. Cylinder seven has perfect compression and cylinder 5 has NONE. So instantly we know that the last time we worked on the car, we swapped the rockers and lash adjusters between those two cylinders. Now we know it has to be one of those two things.

We run and steal an adjuster and rocker off of another motor Jordan has laying around and p0p them on cyl. 5. No compression. At this time, we are starting to get a little mind fucked. "Theologicly" we had eliminated all components that could be the issue. After a little bit of playing around with different ideas. I realize we are really retarded. We never Bled the new lash adjuster before installing it. We pull it out I bleed it and drop it back in. Turn the car over and WHAM compression.


To sum it up. The rocker came off CYl. seven. When we first found the issue and re installed it. it still did not hold compression because when driving the car with this issue the lash adjuster adjusted itself fully outward. Thus when re-installing the rocker it held the valve open the slightest amount causing the loss of compression. Once bleeding The adjuster and re-installing the rocker the problem was fixed.

That being said. Jordan, Matt and I re-installed the Valve cover, the blower, and everything else to get this trurd back together in around 45 minutes. Car fired up and ran like a champ.

We ended up taking the car to a Car meet in town and calling the owner to come to the meet. He had no clue that we had it fixed and was still thinking it was a pretty major issue. It was a pretty cool setup. He was quite surprised to see it sitting there and definitely had to do a double take on that one.

Now giving credit were credit is due, It was quite the group effort doing the work between Jordan, Matt and I. Also a few suggestions from people gave us a good direction to go in. So thanks for the help all. Glad to get it fixed, up and running and all for the price of $0.

[c_mart_28]

Well done guys.

Glad to hear it was nothing major!

[snickerlicker]

Did you blow anyone away in it??

[slow ride]

Is there any chance of piston to valve contact when the lash adjuster is fully extended? Should let them sit installed or turn the engine over by hand a few times to make sure they are not pumped up. Either way it runs now so good deal.

[Phish]

I really dont think that there was any contact in that manner. When we looked at the piston with the borescope we could not see any marks atop the piston. It all looked really good actually. When all re assembled compression was excellent. I really do think there was alot of luck involved with this not causing some major damage though.

[Batwood]

Sounds like it could have been a nightmare! Glad to see it was easily resolved. Pulling the heads on these don't appear to be much fun.

[Phish]

Yeah we were talking about pulling the head. It woudl have been a major pain. We were lucky it was on the passenger side. I dont believe the drive side valve cover can be removed with the motor in the car. So same issue on the driver side would have required pulling the motor.

[BGjohnson]

popping out the finger followers is a known issue with these things. Usually an over rev by downshifting. Glad you guys remembered to bleed the lash adjuster before tearing every apart. It was going to be my suggestion.