Would the double chain set up from the 4.2l work on the 4.0l if one was to change the sprockets and timing chain cover? I would assume that the timing chain cover from the 4.2l is deeper for the double chain, would the timing chain cover match the bolt holes of the 4.0l??

 

You need to check your info the setup is the same for the 4.0 to the 4.2 the chain was a slightly different type but still the same idea

 

It will work, done this many years ago, so forgot the details. The 4.0 engines build from 13-08-2001 also have the morse chain, or also named silent chain, so nothing has to be changed on the cover. I also used the 4.2 oil pump which had the extra oil jets that spray the chain.

But this was on a SC engine, a na engine might be more difficult as you need to have the special sprocket on the vvt unit, and I don’t know if you can swap that, though if you have an AJ27 engine, you could use a full unit from the engines build after the date mentioned.

 

I fit what they call "4th" generation chain set up which is from the AJ34 engine the last of the 4.2s to early engines (AJ26) with no alterations except to one of the guides which is done by the supplier, perhaps I read your original post wrong but I got the impression you thought there was some kind of double chain set up?

No need to change the VVTs everything fits perfectly

 

Just to supplement; there is no 4th generation version from Jaguar, there is only a supplier that modifies the primary chain guides from the 4.2 engines (so 3rd gen), so it can fit a single chain (as was fitted on pre 13-08-2001 4.0 engines). Personally I am not in favor of that one as the modification takes away some good metal weakening the guide, but I have no idea what the life expectancy is with this removed. As with this setup the single chain is used, it will fit on the VVT sprockets. But if as jlfloerke says you can get the 4.2 gear, it is the better option imo.

 

Newer style chain (at least the primary) is available for 4.0. Here is a picture of the stock setup for my 2002 XK8:

https://www.jaguarforums.com/forum/x...ad-news-70163/

 

Sorry for bringing up and old thread...

Is it necessary to use a oil pump with oil sprayers? I know jaguar has made morse chain engines with and with out oil spraying pumps. Would the non oil spraying morse chain engines have another way to lubricate the chain or is this a not an issue? I am assuming the morse chain needed the extra oil but i could be wrong.

My friend has a parts 4.2 STR engine i would like to take the timing gear from to convert my 98 XJR to morse chains. I would like to retain my oil pump(it works fine) and still know the morse chain is properly lubricated.