Peugeot 106 - Emitting Blue Smoke – Compression Test Results

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Sat 30 Jan 2016 18:48
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Pejay

Recent MOT on my old 1998 Peugeot 106 1.1, the advisory stated blue smoke was being emitted during acceleration. I hadn’t noticed this myself before, but can definitely see it now.

It doesn’t seem to make any difference if the engine is hot or cold. The MOT tester thought it was more likely to be hardened valve stem seals due to the age, rather than worn pistons, as the mileage isn’t that high. (75,000).

I’ve just done a compression test and the results don’t seem to be particularly low.... as I was expecting.

The first readings were taken after 5 cycles and the ones in brackets were the maximum reached.

Dry Test.

Cylinder (PSI)

1 – 205 (230)

2 – 205 (230)

3 – 205 (235)

4 – 225 (240)

Wet Test.

Cylinder (PSI)

1 – 270 (275)

2 – 250 (270)

3 – 250 (270)

4 – 260 (275)

Apart from cylinder 4 being a bit higher than the rest, they don’t seem too bad, but I would really appreciate some opinions as to what this points to.

Thanks in advance.

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Sat 30 Jan 2016 19:20
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - elekie&a/c doctor

Apart from a little blue smoke,i would say you got a fairly healthy engine here for an 18 year old car.Valve stem seals are a possible cause but I don't think the expense of fixing them is worth it.

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Sat 30 Jan 2016 19:22
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Wolfan

Worn valve stem oil seals cause a puff of smoke on start up that clears quickly and will also result in smoking when the throttle is opened after a downhill run with the throttle closed. Worn scraper rings will also cause the latter but I think it's more likely that these are are the cause as it's smoking on acceleration. A compression test only shows if valves and compression rings are in reasonable condition not if the oil rings are doing their job.

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Sun 31 Jan 2016 10:34
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Wackyracer
One of the snake oil makers(as alot of posters would say) will sell a product that softens up rubber seals to help rejuvenate them. I think Engine stop leak is one of them.
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Sun 31 Jan 2016 13:27
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Pejay
One of the snake oil makers(as alot of posters would say) will sell a product that softens up rubber seals to help rejuvenate them. I think Engine stop leak is one of them.

The chap who done the MOT suggested I tried some stuff made by Wurth, but I haven't been able to find any online. I was thinking about something like Wynns stop smoke, but that just seems to make the oil thicker!

I hadn't realised there was something to help the rubber seals. If anyone can recommend the best one to try, it might help.

Thanks,

Peter

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Sun 31 Jan 2016 10:55
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Big John

Valve stem seals usually cause blue smoke on first starting or on/just after the over-run(eg down hill) - not usually when accelerating (except when just started)

Check that the oil breather isn't blocked somewhere - this can blow oil past the valve guides/seals with excessive crankcase pressure - if it is this it's an easy fix.

This is common on low mileage engines due to condensation & oil mixing to form oil mayonaise that blocks everything

Edited by Big John on 31/01/2016 at 10:59

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Sun 31 Jan 2016 11:13
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Peter D

How much oil is the engine using. Regards Peter

Edited by Peter D on 31/01/2016 at 11:13

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Sun 31 Jan 2016 13:11
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Pejay

Many thanks for the replies.

I don't do that many miles, but it doesn't seem to be using much oil. I added a little the other week and after 130 miles it was still right on the maximum line.

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Sun 31 Jan 2016 13:19
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Pejay

Thanks for the reply.

I have checked the short pipe that goes to the rocker cover. I'm not sure if this is the oil breather pipe you mean? Or if there is another longer pipe I can clean. There wasn't any of that mayonaise looking oil on the filler cap.

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Tue 2 Feb 2016 02:42
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - liammcl

If you decide to DIY the valve stem seals..
I used one of these
s103.photobucket.com/user/liammcl_2006/media/valve...0
(and bashed it into shape with a hammer)

A tip ... keep a magnet on top , as the collets can spring out all over the place !

This also helps
s103.photobucket.com/user/liammcl_2006/media/valve...6

these are the valve stem seals btw
s103.photobucket.com/user/liammcl_2006/media/valve...1

I think the seals cost about £10, and the tools about the same..

Cheers
Liam

Edited by liammcl on 02/02/2016 at 02:54

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Tue 2 Feb 2016 23:50
Peugeot 106 - Emitting Blue Smoke – Compression Test Results - Pejay

Thanks Liam, but I think replacing the seals would be a bit beyond my capabilities! And as other posters have said, it may well not be the cause of the problem.

Cheers,

Peter

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