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Here's a stupid question for you

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OK,

so I've got two questions. The first one I'm sure must be a joke, but as I'm not a mechanic I have to ask, and the second is serious.

Ok here goes...

A friend has a e30 pre-f/l 323i. It was a single-owner when they bought it, and had been babied it's entire life. Very low kms (Under 100,000), and never left it's home town. In other words it never got used on the highway. We are reliably led to believe it almost never got driven at over 80km/h before my friend bought it.

It's in mint condition and always been fully serviced, but it blows a little smoke. Mechanic's expert opinion is that due to it's history it has glazed cylinders/rings and so it's a bit of blow by. It runs 100% fine and the owner doesn't want to rebuild the motor. Mechanic's opinion is that based on the occasional use it's going to get, that it's not a priority to fix, and the car may as well be driven as-is.

Now for the interesting bit. My friend has owned the car for over 10 years and as predicted by the mechanic, it hasn't worsened, and it runs like a charm. However it does foul the plugs regularly enough that they need a good clean each service (6 monthly to yearly).

Question 1) Another mechanic has suggested pouring a wee bit of brasso down the air intake in a bid to sovle the problem by polishing the cylinders. Sounds a bit like those rumours about pouring sand in your intake to polish it, but as I'm no mechanic, and brasso should combust, I thought i should ask so that someone like Glenn could end the debate for us. So, will it work or will it cause damage? I say the latter, but my curiosity has gotten the better of me.

Question 2) Will hotter plugs alleviate the problem of them fouling so often? and how hot a plug can you get away with on an old m20b23?

Cheers guys, and please only answer if you know what you are talking about.

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yeah it does sound like the rings have closed up a little as said by 1st mechanic, you can try spraying brake clean into the intake when running but it probably wont do much (i wouldnt use brasso personally.)

i would normally say that if you where to get a car in that condition that you treat it gently to start with and slowly drive it a little harder over a period of a few months, just to try and decarbon the cylinders and try and push the rings out. (if you jump straight into it and flog it after a life of being nanad you will probably kill it. but if you slowly work it out a little more each time it can often bring the motor condition back.)

but after 10 years of ownership i would say that the engine is not going to get any better by itself.

you could perhaps try running a thicker grade of oil as it may not pass the piston rings so easily. but in all honesty if it hasnt come right by now it probably wont. hotter spark plugs wont help you either.

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Have heard of that fix before, also Ajax, but never tried either.

When does it blow smoke? On start up & under acceleration after high manifold vacuum (deceleration - down hill)

If so - likely valve stem seals - have probably gone hard.

I had this scenrio with the E12 (also M20) when I bought it in the mid 90's. It was a similar vehicle - one owner 80ish kms, pristine car, 16 yrs old at the time & smoked badly in above description. Replaced the stem seals (in situ) & never a problem since.

As Ollie said - hotter plugs won't help

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dude ... new oil and half a day at hampton and it will be a new car. Sounds like it just needs a bloody good blow out.

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dude ... new oil and half a day at hampton and it will be a new car. Sounds like it just needs a bloody good blow out.

:)

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Does

Italian Tune Up???

Equal

dude ... new oil and half a day at hampton and it will be a new car. Sounds like it just needs a bloody good blow out.

? :P

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what's a best way to remove carbon build up on pistons??

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what's a best way to remove carbon build up on pistons??

Pop in to your local Subaru parts dept and pick up a can of upper engine cleaner. Works much like that seafoam sh*t they use in the states. Follow instructions on the can. Its part of subarus official servicing regime. Works a treat.

OP could try this too.

Edited by -Alias-

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thanks all.

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thanks all.

You might find it is the valve stem seals Graham.. as Grant suggested. BMW's generaly dont glaze up the bores on the older engines

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Pop in to your local Subaru parts dept and pick up a can of upper engine cleaner. Works much like that seafoam sh*t they use in the states. Follow instructions on the can. Its part of subarus official servicing regime. Works a treat.OP could try this too.

Yeah this stuff ^^^ works awesome. you use the whole can as per instructions. i have used it on my Subaru's and several older cars.

There is also a Ford version which is exactly the same stuff (but cheaper if i remember right)

post-5369-1299104575.jpg

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I've passed all the info on. They are of course, going to try the mechanic in a acan first (rather than brasso). And may consider valve stem seals. It uses a fair bit of oil (no leaks) and whilst it smokes most at startup and under acceleration, there is a very small bit of smoke alot of the time, so maybe a bit of both (rings and valve stem seals).

Thanks again. if they do the seals I'll report back.

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