I just replaced the 4.0 engine in my 99 XK8 with a remanufactured motor after having major problems with junk yard engines. I have everything back together but the car will not start. there are no codes but the intake is getting hot and the exhaust is not. Im at my wits end and don't know what to check next. this is not a Nikasil engine and Im getting good oil pressure. does anyone have any suggestions?

 

I don't understand why the intake manifold is getting hot. Have you checked for fuel pressure at the schrader valve on the fuel rail?

 

+1


Need to see if you're getting fuel air & spark, figure out which one you're not getting.

 

Getting fuel at the Schrader valve and have dang near ripped my arm off getting shocked by each coil pack while checking them old school. I have also verified that the cams are lined up proper using the jag timing tool. Coming from working on more ancient cars I would think the timing is 180 degrees off but I cant see how that is possible. I also tried the Nikasil trick of putting a little oil down the cylinders to help with compression nut nothing other than some fouled plugs. I have brand new plugs in again after that. Im completly stumped.

 

The flat spots of the cams might be facing up to indicate they are in time, but where is the flexplate in relation to the cams? Is the hole where you insert the flex plate lock pin in the correct position, with the cam flat spots facing up??

 

I have double checked the flex plate alignment pin but that makes me wonder what would happen if the flex plate got flipped around? if it is possible and the crank sensor is offset by 45 degrees that could explain my issue. I have another flex plate in my shop I will check it in . few hours thanks for the thought.

 

Looking at pick and the alignment would not change if it flipped and I know that it did not as the alignment tool would not work if it did. what about if the cam sensors got flipped or the crank sensor was not sending signal I would think you would get error codes in those cases.

 

Will the bolt holes line up if the flex plate is flipped? Your best bet is to start from step1:
Check compression (over 140 I believe?)
Check spark
Check fuel pressure
If all three line up then we can look at more complicated things..

The ole' suck squish bang blow is true for old and new.

 

I no nothing about this area of the engine / transmission, but I think I read somewhere there are two different flexplates depending on engine number.
Is the one you are using the "old" one or the "new" one - could they be different ?

 

AZ26 has one kind and AJ27 has another kind of flex plate. Slightly different. I would look at that as a last resort UNLESS he for sure is using a different AJ.

 

air+fuel+timing+spark is what I checked on my first start of a new motor last year.

My experience with timing 180 reversed is at least a choke-bang (different type of V8)

Only way I see the intake getting hot without any ignition of gasoline is it's shorted electrically. That would be weird.

 

I dug into and it looks like the timing was off 90 degrees so yuck. shortly after that my wife took the car away due to health so its next trip is to someone else. Hopefully they can get it running as soon as possible.

 

That stinks!