Hi All,
So I recently changed my rev 1 to rev 3 tensioners. Everything went well and reassembled well. I did notice that the right side seemed more slack than the old one but from reading thought it would be due to the new rev 3 depending more on oil pressure and less on spring tension. Left side seemed to be tighter which I read on the forum is normal.

Now after driving I think I hear more chain slack that I had previously, seems like if I bump the throttle with my hand with the hood open I hear just a little bit of slack noise where previously I didn't have any.

I do have almost 120K on the engine so maybe it has some chain stretch.

Has anyone else experienced this with the new tensioners?

 

What is the vehicle MY?

Generally, with the AJ27 having that number of miles, it is best to replace the primary and secondary timing chains, guides and tensioners as the lower guides can break and allow slack in the chain.

If you remove the timing case cover and notice the primary timing chain guides are broken, the missing pieces can be found in the sump.

Changing only the secondary tensioners does nothing to correct the situation.

 

Hi NBcat,

Mine is 97 convertible that was a $1500 save from the dismantle world and really just a toy hobby thing for now unless it starts to come together well and is promoted to a keeper.

I can appreciate that a full replacement would be in order for longevity of motor, but I also read that Primary tensioners typical failures made noise but were not catastrophic so while a good idea not as critical as getting secondary tensioners done and a full swap was more work and money in parts.
I do have an oil pan replacement due to it had struck speed bumps or something several times due to both engine mounts had failed dropping engine 1/2 or more exposing it more to being hit so I will be finding out if any primary shoe failure is at the point of breaking off pieces and if so that will settle the battle and mean it has to be done.

My approach was when recently purchased I had leaking from cam covers, so I thought if I had them off I should do the tensioners if original so bought the rev 3 style and had them ready during gasket refresh. Since they were original I changed them using zip tie method, and made sure to check the cams sync at flat alignment spots and do a full rotation of engine by hand to make sure no vavle collision was going to happen.

I read some posts that said that was normal to have slack due to the tensioner works on oil pressure so I reassembled thinking with oil pressure the tensioner would take up the slack since these new style rely more on oil and less on spring.
After now exercising engine things at idle are quiet but if with hood open I bump the throttle a little I am hearing what I think is some chain slack, maybe I just didn't notice it before and being more critical after the work. I did a bunch more searches on the web and read some more people commenting that they did have some more slack noise like this with new style tensioner, so if normal I don't want to mess with it for now.

 

I suggest you realign the cams using the factory recommended cam tensioning method. The tools are now available on eBay pretty cheaply. 1997 2008 Jaguar V8 Timing Tool Kit 3 2 3 5 4 0 4 2L V8 XJ XF XK s Type | eBay

If there is significant wear in the system, the zip-tie method may not be adequate.

 

I don't think it is alignment issue as i checked after install using allen wrench to remove slack and flat edge to check, if there was any misalignment from chain wear it was there before I started and less than would effect anything but the very fractional difference. My concern is more with overall chain length and tensioners able to maintain tension as well as needed.

I agree proper tools best way to go as I think it would be faster but not necessarily more accurate a method, but obviously required if you plan to loosen exhaust cam gear and would allow to reset to worn chain length.

 

It is a possibility that you have the wrong tensioner on the two sides a check of the part numbers will show that are different for the left and right hand banks and most likely different heights. Might be worth checking.

 

It would be extremely difficult to confuse the Bank 1 and Bank 2 secondary tensioners as they can only be fitted to the corresponding cylinder head.

 

Did you fit the new tensioners using the shorter bolts?

 

Hi All,
Thanks for chiming in.
I did have two different styles of tensioner one for left and right, they were the ford application ones.
I stupidly forgot to order the bolts, so I have to cut down the original bolts and I double checked prior that they would have enough thread to fully seat without being too long. The fit of the tensioners seemed to be just fine, I think they make it where you can't mix them up the way they looked.
Maybe I am just being more critical in my hearing, but I had checked it with the same bump the throttle when I had first read about the tensioners to check if they were healthy.
Have any of you with a higher mileage car with original chains tried opening the hood and using your hand to bumped the throttle a quickly up and off, it is a way to check for chain slack and better to hear it than come to a sudden halt.
When I reassembled I made sure that they flats on the cams where as perfect as would be expected at this age, maybe one degree difference at most and certainly not a tooth off kind of difference.
Well I guess next up is the oil pan and we will see what scraps of guides and tensioners I find in there that might force me to do the full monty with new chains and the primary tensioners and guides.

 

There are several special service tools necessary to correctly align and hold the camshafts in place whilst installing the timing chains. If the camshaft locking plates are not used, along with the crankshaft holding tool, the valve timing may be incorrect.

Under no circumstances is the crankshaft holding tool to be used as a means of holding the crankshaft when removing the front pulley centre bolt. Damage to the drive plate will be the result.

 

If the flats lined up that well, you don't have a problem there. This isn't rocket science. Maybe you are being over sensitive, and maybe the primary chains are noisy due to failure of the guides.

If there is nothing of significance in the pan, I wouldn't worry. But that's just my opinion.

 

Yep I understand it is more involved to do a cam alignment and why I opted to do the zip tie method although if you didn't ever loosen the exhaust cam sprocket then you would have to be not paying attention to change the alignment between the two cams as a tooth off is going to be sever misalignment of cams.

I won't argue that with the proper tools I could have corrected the slight change due to chain wear that was there, but cam alignment is still very close to factory.

My only worry is the new tensioner, and it holding the chain tight. As my wife tells me I am probably being a worry wart about the issue.