I have spare valves from my other engine if one is bent.
I assure youā¦ from experienceā¦ you have a problem in the top end of your engine that can be fixed.
The amount of work you need to do to fix the top end is considerably less than the removal and replacement with another used engine.
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OK, folks, a little help hereā¦how do you determine whether a valve is bent?
I appreciate everyoneās encouragement! I really want this XJ40 back on the road havenāt been able to work on it since itās still too hot right now
Chuck them up in a mill, or drill press, and spin them: it will be pretty obvious.
Check for compression or fill the combustion chambers with kerosene and see if it seeps out on the bench. Roll the valves on a glass plate or spin in the drill press. Look for witness marks on the pistons and valves.
Without some more video evidence its hard for the rest of us to advise you. IMO your timing the first time was significantly off. Did you document and confirm lining everything up right the second time?
I also recall that you were planning to use JB weld to address some corrosion issues on the head? What was the outcome, there?
As much as you probably donāt want to hear this, I think you need some outside local help to advise you. Do you have a machine shop locally that can help you figure this out?
Okay had time to tinker with the car again today, the camshafts and crankshafts are lined up correctly. Changing the position of the distributor around a couple times I was able to find a couple spots that would make the car fire up on first crank, the car would stall out still though. I reved the engine to around 3k rpm and the engine would smooth out with no strange noises, so I have some new hope that it is my timing that is off?? Still, I donāt understand where the timing is off though because I did everything according to the Haynes manual.
My JB weld job seems to be working from what I could tell, I had a similar issue to yours where the rear was leaking oil but after tightening a couple more turns, I donāt see anymore oil leaking from the head gasket. I do think my freeze plug is leaking coolant from behind the exhaust manifold but I want to get the car running first before I tackle that issue.
Any one in Arizona that can help me out? I will pay you
OK, after running it a bit do you have a check engine light on? If so, what code(s) are you seeing when you check the VCM ?
You earlier stated the car was running fine albeit consuming coolant weekly before the head work was done so this may be a long shot - maybe you have a faulty EGR system. Easy check - pull the vacuum hose off the EGR valve and plug the end of the hose then start the car. A faulty EGR system can cause low speed / idle stumbling or stalling. More info here:
[xj40] Engine Stumbling When Decelerating At Low Speeds. EGR Issues??
Iāve only ran the engine for 1-2 minutes, no check engine lights. I will check the my EGR
I do have a fuel fail 22 engine code actually. I deleted my air pump
Here is a video of me revving at a constant 3k
Have you looked at the idle speed motor and the hoses around that area? Did you clean the tip of the motor and the whole housing inside? Easy job.
As Veekay noted in the āMechanic neededā¦ā cross-posting in the Classifieds section āI would look in the direction of air. Either you have unmetered air coming in through some disconnected, or ruptured line,ā
I would check the connection of the air bellows to the throttle body (#5 to #1 in this diagram):
as this is fiddly to fit snd has been prone to a mis-fit on the lower (not visible from above) side.
Also check that the hoses connected to the air intake elbow (#7 in the diagram) are intact as this can also.be a show-stopper. - the engine will fire up but not run at idle. Been there and done that!
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Purchased a engine which I was told was a 4.0 1990 engine but turns out from the vin it came from a 1988 3.6 xj6. Which I believe is not swapppable? Engine looks good but is otherwise useless to me? Bummer