Club 80-90 Forums

Hi JX Engine experts,

I have found a post that says that JX engine valve seals can be replaced without removing the head in about 2 hours. Compressed air and special tools are mentioned but no indication of how it's done.

Has any one done this and what is procedure?

Ken K

Yes I replaced the valve stem seals on my jx ....made no difference!!so why do you think the seals are gone?

JX is an indirect injection engine with almost flat pistons, so set at TDC on each cylinder in turn, the valves will not drop into the cylinders. After removing the camshaft there is no risk of valves hitting pistons but you will need to check valve timing at TDC on number one cylinder/cam pulley & diesel pump with appropriate tools on refit before starting.
After pulling out the buckets (keep them in order to ensure cleareances don't change) We used a home made bar that fastened to the cam cover studs and a lever with push down tool to remove the top washer and collets . You could then remove the spring and go down with the valve stem seal removing pliers (like snipe nose pliers but shaped to go around the seal). The new valve stem seals were then knocked into place with another special guide tool (mushroom) and then the spring/washers & collets replaced.

Like I say, I am reminissing my old school days working at a main VAG dealership and using mostly official VW tools. So if you intended to do this you would need to make several tools yourself to achieve the desired effect.

The compressed air bit was for petrol engines where the valves would drop too much to refit the top collets. The tool basically a bored out spark plug with air line adapter attached......it worked very well.

Martin

dave friday wrote:Yes I replaced the valve stem seals on my jx ....made no difference!!so why do you think the seals are gone?

Valve stem oil seals were/are a common problem on all 4 & 5 cylinder VW/Audi's of that era. They go rock solid with age and heat allowing oil to be drawn down the guides and valve stems into the combustion chambers.
Typically diagnosed by looking for a puff of smoke on first application of the throttle after a long overun (slightly different on a diesel because of the difference in induction) however, these seals fail on diesel & petrol alike.

Unfortunately, doesn't cure high oil consumption due to worn rings and bores or turbo leak issues however, is a contributer to high oil consumption that shouldn't be ignored.

Martin

Thanks Martin for the very useful reply, the engine has only done 30,000 but uses lots of oil, turbo is reconditioned and there are no leaks.

Basically I have eliminated everything apart from valve stem seals and cylinder wear.

I am wondering if the engine was nursed when fitted and the bores are glazed.

Ken

on my engine the high oil consumption was due to the top and bottom rings [1.5mm gap!!] strangely the middle rings were all ok [.4mm gap ].
this was 50,000miles after a complete rebuild [rebore etc ] perhaps I was given some poor quality rings? [the ones that wore out ].

kenkelso wrote:Thanks Martin for the very useful reply, the engine has only done 30,000 but uses lots of oil, turbo is reconditioned and there are no leaks.

Basically I have eliminated everything apart from valve stem seals and cylinder wear.

I am wondering if the engine was nursed when fitted and the bores are glazed.

Ken

I had a NEW shaped Beetle with an eight valve 2 litre petrol engine, that would use a scaringly high amount of oil (over 1 litre every 1,000 miles)
Over the 4 years I owned the vehicle this dropped to less than 1 litre between its 10K main services.

The car had been owned by an elderly American (in his late 70's) from new and although I never thrashed it and my mileage was less than 6K a year, my 'free revving' driving style obviously was all it needed to de-glaze and seal the leak by.

Martin