Current thinking is valve stem seals...

GazHyde

GazHyde

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M Power
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Model of Z
Z4 MR
Started Rosie up earlier and recorded the experience for posterity. It did clear after a few restarts and letting the engine idle. Shall probably end up in the Zed shed soon where we shall start disassembling the top end of the engine.

Excuse the sooty pipes, but I think you will understand why they are! She still sounds awesome though...

Discuss :whistle:

View: https://www.youtube.com/watch?v=5MG3J4k1nlA
 
As well documented I'm no mechanic but don't valve stem oil seals tend to go on lower mileage cars through lack of use? They go hard don't they? How many miles has yours done Gaz?
 
118k at the moment Dave. Being honest it really needs further investigation, need to get the spark plugs out and have a look. Lee has got the kit to do a compression test as soon as his Dads Jag is out of the #JagShed.

Should know more once that's done.
 
I guess you have checked the crankcase breather etc quite a lot of work lifting the head
 
Jag shed lol! Well fingers crossed it's nothing major. I had similar on an old daily driver some time back, after a long investigation it turned out to be a split vacuum advance pipe. Cost a couple of quid.
 
madleemark said:
I guess you have checked the crankcase breather etc quite a lot of work lifting the head
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Yeah, we will be looking at that along with any other items that seem appropriate. Although for giggles, I'd quite like to strip down an engine. Never done it before, so would make a good little write up for on here!
 
Grumpy said:
Jag shed lol!
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Don't ask. We could have refurbed two Z3 subframes in the time it's taken to strip just the rear suspension out of this one - and we haven't even fitted anything back on yet!
 
key thing is cleanliness, clean off as much of the engine as you can, be good to freshen up your engine, polish the valves and such, has it been using a lot of oil
 
madleemark said:
has it been using a lot of oil
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No more than most M54B22's seem to. We ran an engine flush through on the last oil change which helped the consumption a little.
 
GazHyde said:
Don't ask. We could have refurbed two Z3 subframes in the time it's taken to strip just the rear suspension out of this one - and we haven't even fitted anything back on yet!
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When I was a brave little chap I changed the head gasket on a straight 6 4.0 jag. I enjoyed doing it and after getting a guy into set up the timing afterwards it worked!
 
Not too sure that is a valve stem oil seal problem to be honest. Usually with that you get a single blast of blue smoke on start up not on each acceleration.

Tony.

ps. On watching the video again, it doesn't smoke for a few second after you started the engine, only when you revved it, so I don't think it's valve stem oil seals. If it was, the oil would have run down the valve stem ready to burn as soon as the engine fired up, it doesn't do that.
 
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in the dim and distant past when I worked on BMW's for a living, the M20 was the common engine in 3 & 5 series. We would commonly replace rings and valve stem oilseals due smokey engines. The carb'd versions would start to run rough when they started to breath due to rings. You could cheat a bit with those by disconnnecting the rocker cover breather and running a length of hose down the engine bay to breathe to atmosphere. The injected ones didn't like that trick though.

Valve stem oil seals would go hard as suggested by @Grumpy.

Smoke on start up could suggest valve stem oilseals, small amounts of oil passing the seal and collecting either in the combustion chamber if the valve is open, or sitting on top of the valve if closed.

Smoke on hard acceleration though, points more towards rings.
If you remove the oil filler cap while its running, does it "breathe" fumes?
Are there traces if oil in the inlet tract where the engine breather is connected?
Both would suggest a bit of ring blow by.
static compression test will highlight this.
How much oil is it actually using?

If its any consolation, the aeroplane burns and breathes half a litre of oil per hour. If we are flying out to another airfield, we take a bottle of oil with us!
 
In that case I'd forget all about it!

More importantly, look how dirty Rosie's bumper is! She needs a wash!!:(
 
GazHyde said:
I love my zed. Not even the slightest puff on startup this morning bless her.
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i'd say it was condensation then due to the cold weather, mine is proper steamy when first out of the garage but nothing on high loads.
 
It's hard to make out in the video due to the angle and the sun back lighting the smoke making it look pale. It was thick, blue and stank to high heaven.

Oh, and Rosie always needs a wash! :bag:
 
Hey Gaz, looks to me like the engine is running really rich on start up, did you cup your hand over the exhaust and then smell it, that would give you an indication of the problem!

Mike
 
Go on, you know you want to. Take it to bits, that is. Have ordered the seals and gaskets ready to do my 2.2, now need a timing kit to make sure I get that bit right. Will be trying it without taking the head off, just hope it is the valve stem seals, as I've already changed the CCV valve and given the engine plenty of flushes and oil changes. Would be nice not to have smoke trail following me around.
 
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