Ok Petrol Heads

[Les Henson]

I had a look at a S3 with a Rover SDi 3.5 engine in that rather badly needs the valve stem seals doing in both heads. While it doesn't look too bad to remove the drivers side head with the manifold still attached, the other side looks near impossible. The rear-most exhaust manifol bolt can't be got at due it's low position and proximity to the footwell, the bolts that hold the downpipe to the manifold are extremely close to the top of the chassis rail, so again it doesn't look as if they can be undone either. Have any of you got this engine in your motor and have had to take the heads off with the engine in situ?

Also, are the rockers the shim type? I thought they were adjustable, but it appears not by the usual screw and lock-nut method anyway.

Thanks in advance.

Les.

[jwriyadh]

If you need to give yourself room to work on the N/S head try removing the engine mounting rubbers and swinging the block to the O/S. Should give enough space to work. Whoever installed the conversion obviously did not want alter the bulkhead more than necessary.

The valve gear does not need adjustment if all the parts are original and standard. The gaps in the valve-train are taken up by the self-adjusting hydraulic cam followers.

If only the valve-stem seals need doing then consider the compressed air in the cylinder and one sided valve spring compressor method. The heads stay in place.

jw

[Les Henson]

Thanks for the reply JW. Good idea with swinging the engine across and I'll probably do it that way. I think the heads will have to come off though as this engine has been burning a LOT of oil for quite a while and is no doubt badly in need of a de-coke if looking at the plugs is anything to go by. The heads sound just like badly adjusted tappets, so I did wonder about adjustment. Do the hydraulic ones clog up or stick, causing the rattle. Any idea if they can be taken apart, cleaned, and re-fitted with any degree of success?

Thanks anyway.

Les.

[Hybrid_From_Hell]

Les,

If the top end is rattly is most prob the cam worn, this gives excessive clearance in the valve tappet rods (which can also wear they should be "Round" at each end, often when worn they have a little point - if so they are for the bin too), and the whole lot then rattles.

The followers should rotate, again with crud they can get stuck, and then they wear in the top,.

Often best course of action is a cam kit, this will often inc new cam, followers, rods, gaskets etc.

Just pray the cam bearing are ok, normally they are, but they can wear.

False economy fitting part of the kit, as it may be quiet for a while, but the mix of old and new partsd means fast wear and then rattles agin !

Use composite head gaskets IMHO they make a tiny compression diffierence, but are so much betyter than tin ones as they cover up the scrapes and cuts that often are on older engines, much more forgiving.

Be very wary of shoving a load of FORTE engine cleaner in the de-crud the top end - i've known it clean the bottom end out too, athen the whole engine knocked as the crud was what was stopping the big ends kniocking !

Nige

[jwriyadh]

Check the state of the cam by measuring the valve lift on every valve. The appropriate figures are in the manuals.

As you remove the rocker shaft slide the rockers to one side and check the wear on the shafts.

Unless the engine has a known date of skimped rebuild I would prepare the owner for a large list of what needs replacing.

jw