Yes, the valves are not aligned symmetrically about the cam, so chain tension will increase and decrease relative to the cam's rotation position.

 

Thanks for the info. I will now button up the timing chain cover and start doing the other things I am planning to do to get 'er running.

Mick

 

Hi Brake Buster,

You have posted a great deal of information about replacing the tensioners. I'm unable to view the pictures that you posted and was hoping that you wouldn't mind emailing them to me. My address is Stephens_Ant@yahoo.com. Any and all help is greatly appreciated from all.

Thanks

 

I plan on chaging mine this weekend with the kit I purchased from Chris on Ebay. Wish me luck.

 

Nice to see the dealer sharks trying to cash in as usual, I made my own camlocking tools , cost around £10 for the 2 , thats materials, labour ... obviously not the dreaded VAT.
Dealer price $120 plus! come on! ....... how do you leeches sleep at night? Any small machine shop with even basic equipment would make 2 in 15 mins

 

That's the only statement you made with any real value.

Let me pass along something that my mom used to say to me. "If you don't have anything nice to say, don't say it at all."

 

Looks like you should go into business.

 

How are you sure the crank is in sync with the cams? The primary chain could be stretched or have jumped a tooth. The primary tensioning blades and tensioners probably look like the tensioners you removed.

 

If anyone is able to view those pics would you email them to me at
stephens_ant@yahoo.com

I would greatly appreciate it very much.

 

great info, I have seen Diy's on the secondary tensoners but nothing on the primarys.
I'm about to do them on my XJ8 anyone having any info would be apreciated.
Thanks POP

 

There is a very good write-up of primary tensioners and loads of photos here

Tmingi chain and tensioner replacement

 

I've seen a post somewhere that used zip locks to fasten the chain to the sprocket - you have to be careful in undoing/redoing the cam back up not to snap it - can be done though,apparently. Out of interest, if you remove the sprocket with the cam(s) locked how do you ensure it goes back on in the same place in the absence of timing marks/keyway etc. - mark it before disassembly???

 

What is the reason for chains to be replaced with tensioners?? Cant you just replace the primary and secondary tensioners?? These kit would be a lot cheaper without chains!!

 

Batroute and Green01XKR, I went both ways. I replaced the secondary tensioners with the zip tye method first. Once the chain is tyed to the sprocket, you have secured the timing as it was. Whether it is the proper timing is another matter. If you had tensioner failure, as I did, you could be off due to the chain jumping a tooth. The chain may also be damaged since it contacted the metal shoe of the tensioner. I decided to go the full route including chains. Once you have the timing cover off, you never want to go back there again, so replace the chains; it's really not that much more. The primary tensioners didn't look too bad, but the alignment blades were worn and cracked. I only had 66K miles, so maybe another 30K before another failure. In the end, having everything apart gives you the opportunity to get to factory alignment with new parts. The peace of mind is a bargain at twice the price.

 

Guess thats what i have to do then, since driver side chain is deff in contact with tensioner metal shoe... How does one remedy chain jumping a tooth(assuming no damage to valves) ??

 

If the secondary chain has jumped a tooth, the engine will run rough. With the timing cover off, you can turn the engine slowly by the crankshaft bolt and watch the rotation of the camshafts. There are two flat places at the ends of the camshafts nearest the chain sprockets. If there has been no jumping of a tooth, then somewhere in the rotation of the engine the two camshaft flats should lie in the same plane. That is, a flat bar would sit across both of them. If you can't see that condition, then the timing has slipped.

 

hi everybody, i have a simple question. i just replaced my heads on a 4.0 aj27 rented the tools locked the crank set the cams in rolled them around to the flat spots put the cam locking tool on installed everything my question is i rolled the motor over by hand 10 or 12 times the chains are tight but when the exhaust is rolling off the 3rd cylinder and starts to roll off the 7th cylinder the secondary chains on the opposite side of spring side always are loose a little bit is that right or did i screw it up? HELP.

 

post #81 of this thread...
"Yes, the valves are not aligned symmetrically about the cam, so chain tension will increase and decrease relative to the cam's rotation position. "

 

Guys , I am in dire need of the tools to do a complete timing chain and tensioner replacement, I really do not want to pay $250.00 to $499.00 for them, If some one can rent them, Loan them, to me or sell them to me at a reasonable rate, please let me know. I have parts coming via ups, and want to start this job this week. Thank you in advance.

Ken email: manningcontrol@gmail.com

 

I'm about to change my secondary tensioners(no noises yet - I just want to sleep at night) and thought I had seen something somewhere about removing a spacing plate underneath the gen.1 units when replacing with the later spec. - I've searched the forum but can't find anything - can anyone advise whether this is correct or not - apologies if this has been covered before?