www.jec.org.uk

Dear all

It's me, yet again. Thanks for your patience. I think I am suffering from paranoia associated with owning and running a car far better than anything I've touched before

A couple of questions. When I start the engine, I think I can hear a very slight rattle which isn't there when the engine is warm. But if I hadn't read so much about the dreaded timing chain tensioner issue, and only having driven ordinary (and relatively much noisier engined-) cars before, I duoubt I would even have noticed it. It really is the slightest tick, tick, tick. Is it likely to be something problematic, or am I listening too hard?

Second thing. If it is the tensioners on the way out can anyone supply a list of all bits and tools needed to replace the most accessible (and most often faulty) ones and suggest a supplier of parts, please? The engine has done around 100k.

Thank you very much in anticipation

Kevin

If it is just a 'tick tick tick', it probably isn't the chains. They are generally described as a pronounced rattle.

It is more likely to be the accessory drive belt you are hearing.

Damian

could be a number of things making the noise

first of all, the tensioners wont actually give you a rattle unless the plastic shoe has come off and the chains are running on metal , and that would be a really nasty noise and FUBAR your engine......

second thing could be the VVT gear on the front of the cam castings, if your car has variable Valve Timing , all 4ltrs do , then these need a little bit of oil pressure to get going and take the noise away , this is NOT detrimental to your engine, and its a get used to it kind of noise , thinner oil will get there quicker and reduce the noise quicker, but oil presser is harder to maintain with thinner oil ( 0w50 etc )

as mentioned, the serpentine belt can/does make a noise in cold weather, the belt sticks in shape and as it goes round it ' thumps ' the tensioner and makes it spring back, as the engine warms the belt becomes more flexible, and the noise goes away , this is more prevalent on colder morning ,

other engine noises are the serpentine belt pulleys , these squeal at startup , but get quieter, if they squeal, then they need changing

other than worn bearings in the coolant pump , air-con unit , power steering pump and alternator, no other noises should be heard

hope this helps

BB


ps, as for parts for the tensioners, see my post on the XJ8 forum ( same engine )

Thank you, thank you, thank you!!

I doubt that my engine has the metal tensioners fitted, so I'll save up for the parts over the coming months and do the job in the summer. It's a great relief to know that I am unlikely to break the engine in the meantime

Kevin

Kevin,

Best of luck with the car. If the car is on the original tensioners with 100k, I wouldn't wait around too long before changing them! You really can't guarantee to get warning before they let go. Ask Rob Jenner to show you some photos of what happens if they let go! it'll make you save up very fast!

Good luck

Paul

could be a number of things making the noise

first of all, the tensioners wont actually give you a rattle unless the plastic shoe has come off and the chains are running on metal , and that would be a really nasty noise and FUBAR your engine......

second thing could be the VVT gear on the front of the cam castings, if your car has variable Valve Timing , all 4ltrs do , then these need a little bit of oil pressure to get going and take the noise away , this is NOT detrimental to your engine, and its a get used to it kind of noise , thinner oil will get there quicker and reduce the noise quicker, but oil presser is harder to maintain with thinner oil ( 0w50 etc )

as mentioned, the serpentine belt can/does make a noise in cold weather, the belt sticks in shape and as it goes round it ' thumps ' the tensioner and makes it spring back, as the engine warms the belt becomes more flexible, and the noise goes away , this is more prevalent on colder morning ,

other engine noises are the serpentine belt pulleys , these squeal at startup , but get quieter, if they squeal, then they need changing

other than worn bearings in the coolant pump , air-con unit , power steering pump and alternator, no other noises should be heard

hope this helps

BB


ps, as for parts for the tensioners, see my post on the XJ8 forum ( same engine )

Don't think 4Ltr XKR's have VVT , but I might be wrong ,

Nik

i think we may both be right , in a way

from what i remember, the supercharger engines dont come with VVT , but NA cars do ?



BB

could be a number of things making the noise

first of all, the tensioners wont actually give you a rattle unless the plastic shoe has come off and the chains are running on metal , and that would be a really nasty noise and FUBAR your engine......

second thing could be the VVT gear on the front of the cam castings, if your car has variable Valve Timing , all 4ltrs do , then these need a little bit of oil pressure to get going and take the noise away , this is NOT detrimental to your engine, and its a get used to it kind of noise , thinner oil will get there quicker and reduce the noise quicker, but oil presser is harder to maintain with thinner oil ( 0w50 etc )

as mentioned, the serpentine belt can/does make a noise in cold weather, the belt sticks in shape and as it goes round it ' thumps ' the tensioner and makes it spring back, as the engine warms the belt becomes more flexible, and the noise goes away , this is more prevalent on colder morning ,

other engine noises are the serpentine belt pulleys , these squeal at startup , but get quieter, if they squeal, then they need changing

other than worn bearings in the coolant pump , air-con unit , power steering pump and alternator, no other noises should be heard

hope this helps

BB


ps, as for parts for the tensioners, see my post on the XJ8 forum ( same engine )

Don't think 4Ltr XKR's have VVT , but I might be wrong ,

Nik


im with you on this one nik , i didnt think they had vvt in the 4 ltrs , the 4.2 does ( i think) lol

i have the XJ8 , its a 1999 4ltr Sovereign , with the AJ27 engine , essentially the same as the XK's for the same timeframe .

it has VVT .

the solenoid for this can be seen on the top front of the rocker cover with a two wire plug on it from the engine loom

they defiantly did it

BB

Should have made my post clearer

4 Ltr XKR's Don't have V VT

4 Ltr XK8's Do have V VT ,

Nik

PS I believe some later 4.2 XKR's were fitted with V VT

Should have made my post clearer

4 Ltr XKR's Don't have V VT

4 Ltr XK8's Do have V VT ,

Nik

PS I believe some later 4.2 XKR's were fitted with V VT

no i got what you where trying to say

i think we may both be right , in a way

from what i remember, the supercharger engines dont come with VVT , but NA cars do ?



BB

isnt that what i said earlier ?

BB

Hi

this is my first post. I hope it works!

Do you have please the part number for the new and good timing chain tensioner to replace the tensioner on my 1999 XK8? There is a reference on one of the posts to the XJ8 forum but i cannot find any reference to the part there. I nhave the photos from the june 2009 magazine but not the part number.

Many thanks

Ed

Hi Ed,
Trust you received and found my response to your pm of help. Mike.