Hi everyone,
Trying to find out if a 1999 AJ27 block is compatible with a 1997 AJ26 engine?
Thanks,
JAY111

 

Hi Jay,
When I was looking for an engine for my '97 I was told only an AJ26 engine would work.

 

you can build any 20 series engine with any 20 series block.

to convert a 27 block you need to swap the flex plate. heads and cams have to come off the 26

 

Thanks

 

So the answer is as long as I use the components from my AJ26 the AJ27 block will work?
Thanks,
JAY111

 

The BASIC 4.0 blocks (AJ26,AJ27,AJ28) are ALL THE SAME EXCEPT the late ones with the MORSE STYLE PRIMARY chains.

The UPPER SUMP, HEADS, front timing covers as well as the sensors and some minor bolt on parts can be swapped around to create whatever configuration you need.

I have a 2000MY XJ8 with a 2002 AJ28 4.0 block.(S-Type) I just used all the other parts off the AJ27 engine because the crank was seized.

Put both engines side-by-side and make a 'good-one' from the parts to get the one you need.

ETA....... SUPERCHARGED was not addressed but the pistons are different. (also no VVT)

 

Thank You for the information, so I could use an AJ28 with steel sleeves if I want if I also change the rings to go with those cylinders?
Thanks,
JAY111

 

27s after august 2000 are steel also

less time wasted

 

Thanks,
2002 block will work correct?
Jay111

 

The UPPER oil sump from a later engine WITH 'MORSE-STYLE' primary chains use a different oil pump and pick-up tube assy!!!!!!!!!!!!!!

The 'old-style' upper sump will NOT bolt on to the bed plate due to the different oil passages.
The upper sumps are all different between XJ26,27 and AJ28. That is what you swap as well as the heads and other parts.

I'm pretty sure the crankshaft bed plate will not 'line-up' with oil pump inlet/outlet if they are swapped around?

Just stay with LIKE-FOR-LIKE as far as primary chain style and you won't have issues.

 

OK so here's what I've got. 1997 XK8, dropped a valve put a hole in the piston and scored the cylinder. I understand that you can't hone a Nikasil cylinder so if I have to replace the block I would rather have the steel liners. I ordered a 2001 block with the steel liners complete down to the sump. Here's my question, with the 1997 engine and the 2001 block can I build an engine?
Thanks,
Jay111

 

Also the newer block had the old style primary timing chains if that helps.
Jay111

 

Your problem is that the AJ26 heads are not serviceable to swap to the replacement block.
You will at least need to swap the bank 2 intake cam.

PLENTY of threads on the swap if you search the forum. (this subject has been 'beaten-to-death)

 

Why will my AJ26 heads not work?
Jay111

 

BECAUSE you dropped a valve?

 

I have purchased a replacement head. Sorry to be such a pain but I would like to get this right before I start. I have all the parts for the 1997 AJ26 (bad Block) I have located and purchased a 2001 VDP block ,it had old style timing chains and tensioners. The chains and tensioners on the AJ26 were replaced 5000 miles ago and are still in great shape. My Question is can I use the 2001 block and transfer everything from the AJ26 to the new block? if not what are the issues?
Thanks,
Jay111

 

YES.
Transfer all the good parts to the replacement engine.
Put them side-by-side and pick the BEST correct parts to assemble the AJ26 engine.

The AJ26 upper sump ONLY has the OIL PRESSURE switch and the AJ27 has a TEMP SENDER as well.

You can leave the AJ27 upper sump on the block and just don't plug anything into the temp sender. (no wire on the AJ26)

The BANK 2 CMPS will need the intake cam for the AJ26 engine management (single lobe reluctor) but if you install AJ26 heads, that will be taken care of.
Don't forget the Torque Conv Drive Plate. (they ARE different)