Hi All, it’s been a long time between posts. I have a derelict 5.3 v12 xjs that I’m thinking of using in the “shitbox challenge”
The whole point is to raise money for cancer in a low value shitbox. Thus I’m trying to make this car usable, not fixed properly.
Anyway it ran when it was parked 5 years ago.
It would not turn over. It’s not seized in the bores.
It was seized in the cams and valves.
I have freed up all but 1 valve which is all the way down. But the engine turns over freely.
Question is, is this an interference engine?
I figure the valves are vertical, so the timing being correct at worst if it hit it should close the valve.
Not bend it.
I’m not sure if I just have one more stuck valve or if I have to pull the head to replace a bent valve.
I have 195 psi on the other cylinders, so although this engine is crappy it’s perfect for this event.
A second hand engine is locally double the cost of the car’s value limit so it’s not an option.
Any advice is greatly appreciated
Good news is the valve has freed up.
Soaking in penetrating oil mix for 3 days it was still stuck.
So I heated the cam carrier with a hair dryer. After approximately 10 mins it popped back up.
I now have good compression on all cylinders, which answers the question of interference. In the very least, the exhaust valves are not interference.
I strongly suspect all valves are non interference as they are set up the same way.
You MIGHT be lucky and get away with no damage but it’s not certain. If you’ve ran it, there’s nothing to lose. You could try the old “ rope trick” through the plug hole,turn it over by hand, with the plugs out? See if that closes the valve. Before trying this I’d attempt to fill the combustion ( as much as you can with a good penetrating fluid, leave it to soak for a day or two.
Thanks Nigelplug, It seems I have been lucky.
I mixed clean oil and thinner 50:50 and poured down all bores and over the cam followers that were stuck. As mentioned in previous post a hair dryer was able to free the last valve.
Now with good compression on all cylinders I can start to reassemble.
Thankyou for your input
.[quote=“Nigelplug, post:3, topic:440418, full:true”]
You MIGHT be lucky and get away with no damage but it’s not certain. If you’ve ran it, there’s nothing to lose. You could try the old “ rope trick” through the plug hole,turn it over by hand, with the plugs out? See if that closes the valve. Before trying this I’d attempt to fill the combustion ( as much as you can with a good penetrating fluid, leave it to soak for a day or two.
[/quote]