Im trying to do timing chains on my 98 Xj8 been messing with it for two weeks off and on and its not working PLEASE HELP!!! I am doing one side at a time i have the left head off and the right head is on. (just got done rebuilding bottom end) and its still hitting when I try to put it in time.

Heres what im doing is this right?

1. Put crank plug in ( yes its in the right hole)

2. Bring the flats of cams up and lock them in with cam tool.

3. Slide on vvt, eXhaust spocket and secondary chain. ( made sure that the vvt and eXhaust spocket were a half a tooth off from each other)

4. Put on straight guide and rotate eXhaust spocket ccw to take up slack on drive side of primary chain.

5. Put on curved guide and tensioner and put wedge inbetween.

6. Used timing chain tensioner tool and put ccw pressure on drive side of chains and tightened down eXhaust spocket and then the vvt unit.

Took all the tools off and turned it over by hand it turn over a little then hits. Its the back two valves hitting on the eXhaust cam hitting the very back piston.

It has the right cams in each head and theres no bent valves and nothing has falling in the cylinders that would cause it to hit. what could be the problem THANK YOU IN ADVANCE FOR ANY HELP

 

Smitty:
Sorry to ask again, but I do not know - Can the ring gear assembly be put on the crank shaft out of phase? What parts besides the piston, rod and valves did you change? Other than these and what you mentioned, it is really hard to imagine what could screw up the timing. You do have the right length rod in that posiition, right?

 

One other idea- could the cams be on the wrong side? (Bank A exhaust cam on Bank B head) Don't know if they are identical...

If the flats lined up, the only thing left is the triangle mark being in the wrong place on the crankshaft (Although I would expect more than just two valves would hit) OR The cam is pressing down the valves at the wrong time- thus my hypothesis.

 

Is there any slack in the cam chains ? It sounds like your exhaust cam is retarded - I mean those exhaust valves should be closed before that piston comes up high enough in the cylinder to hit them on the exhaust stroke.

 

I thought the fleXplate only goes on one way. The cams are in the right sides of the head for sure. Theres no slack in the chains. I just put bearings in the bottom end and put a used crank and rods from the same year motor only differnence was my motor has steel liners and the motor I took the parts from was the nikasi liners (I dont think the rods were different I know the crank had the same numbers as mine) . Im out of ideas????

 

I assumed that your #3 reference to 'half a tooth off' was referring to the left/right bank primary chains on the crank. Is that true? That is how it should be.

Here is the JTIS primary chain alignment section:

https://www.jaguarforums.com/forum/j...prokets-54603/

 

Ok smitty-
Are you SURE the flexplate stepped pin was in the crank when you alighned the plate? I do not remember what it looks like, but the literature indicates that is the alignment method for the drive plate. Check your crank position relative to TDC when the pin is lined up- TDC is not the alignment point, but either someone can post the offset, or I will compare mine, if you like.

 

The half a tooth Im talking about relates to the vvt and the eXhaust spocket for the secondary timing chain I read that the vvt and the eXhaust spocket should be a 1/2 a tooth off is this correct? maybe I have this messed up? Also I thought the drive plate bolt pattern would only go on one way maybe theres more then one more does anyone know for sure? THANKS IN ADVANCE JEREMY

 

Yeah something else is wrong as those valves don't hit if a secondary timing chain fails. Something else is wrong.

 

yzedf:
Sir, I am afraid you are just plain wrong.

 

As far as I can see in the literature, the flex plate lines up with a stepped locating pin. If you don't remember the pin, I bet that is your problem. Why not post a question for motorcarman or one of the other jagtechs with flexplate alignment in the subject.

 

To be sure that the timing is set right, you can check cylinder 1 on the A bank, which should be 45 degrees ATDC when the plug is installed.

 

avos 45 degrees ATDc? TDc to me always meant the number 1 piston is up at its highest point in the cylinder. When you say 45 degrees what do you mean? Its half way up 3/4s way up? Thanks buddy

 

sparkenzap thanks for your input I will post something about the drive plate and see what they have to say about it

 

smitty:
The plugged crank position is where avos said so that the cams can turn without hitting any pistons. And if avos said it you can take it to the bank.

 

Banks can fail too


Once you have the cylinder 1 at TDC, turn the crank another 45 degrees, then the oblong hole should be alinged. If the pin was gone as Sparkenzap mentioned (which enables you to place the flywheel wrong) it could be at least 45 degrees of, so you should be able to confirm if the flywheel is fitted correctly the to the crankshaft.

 

Ok I brought the number cylinder on Bank A all the way to TDc and turned the crank another 45 degrees and sure enough its off. The way I had it the number 2 cylinder on Bank A was at the top of cylinder and number 1 was half way down. Now I just have to figure out how to align the drive plate. THANKS SO MUcH for your guys help and ideas.

 

Smitty
I uploaded the V8 engine coarse guide to this site.

Go to the General Tech forum and the 'sticky' section will have the
JAGUAR FORUMS LARGE FILE DOWNLOAD AREA.
Download the Engine coarse guide 168 and every question you could ever ask will be addressed in the guide.

bob gauff

 

bob:
Thanks once again for you generous contribution of your time to furnish us with accurate information not available to the enthusiast community from any other source.

 

You are welcome.

I also have the earlier V8 Engine Coarse Guide 180 but it is ONLY for the V8 and the later 168 has both the V8 and V6 so that is the guide I uploaded.

bob gauff