Low compression

[s13adam]

Hi guy

I was wondering if anyone could offer some advice on my potential problem and I'll try and keep it short

So I left the car idling this morning and it started to kick out a lot of smoke, mainly blue, in traffic it clears up

I nipped up to my mechanics and he checked the oil and it looked to be over filled quite a bit on the dip stick so am currently draining it and refilling with fresh oil

Whilst I was there I did a compression test and the first 2 cylinders were around 140, next was 110 and then closest to the bulkhead was 90

I've done a bit of searching on here and the engine was warm as most say, I didn't plant the throttle as it appears on here most people do and I've read about a 'wet' test but have no idea what one of them is

Could anyone offer some words of advice?

Adam

[pointz]

Re do the test with wide open throttle as it does make a difference.

If readings are still low then a wet test is basically a teaspoon of oil down the bore through spark plug hole then re-test. (This will highlight if it is a ring problem)

If test result is still poor you may have worn valves.


The smoke you say clears in traffic. So when you are stationary theres no smoke?

[s13adam]

Sorry

There is smoke stationary but only when it's warm and after a few minutes of idling

I must also ask and fully expect to get reprimanded but what oil should I put in? I've had a look but can't find it anywhere

Adam

[Jonny Wilkinson]

Fuchs Titan Supersyn 10W40 (available from ebay or Opie Oils on here).
Use an OEM or good quality pattern oil filter (like Blueprint) and drain all oil (jack on passenger front to help draining).
Set out exactly 3.5 litres of oil and use some of it to prefill the filter.
Refit drain plug (this is important lol)
Screw on filter.
Put remainder of the 3.5 litres in through filler cap on camcover.

The dipstick is the work of the devil and gives false readings.

The smoking may be down to overfilling. You may need to give it a 50 miles or so to completely burn off, if its got into the intake/plenum via the breathers due to the overfilling. It may be a good idea to take off the breathers and clean them out inside.

Redo the compression test on a cold engine with wide-open-throttle having removed all the spark plugs and the fuel pump fuse. Crank for 8-9 seconds on each cylinder and reset the gauge each time.

As Rich says, if the cold dry test gives bad results, try with a warm engine then try with a drop of oil in the bores (wet test).

Then report back.

[s13adam]

Well changing the oil seems to have cured the smoke on idle

I only got about 3 litres in and it came up to the top of the dip stick from what I could see, oil light hasn't come on so I assume the level is ok?

Only time will tell as I just ran it in the shed and didn't take it out and about to try and mimic what happened this morning

I'll try another compression test at some point and update this when I get a chance. Weird as the car runs perfectly and only has 65k on the clock

Is a rebuild on a ca18 expensive does anyone happen to know?

[Jonny Wilkinson]

DO NOT trust the dipstick. Oil light only tells you that the car is broken coz you didn't put any oil in

0.5 litres of oil difference in a sump that only takes 3.5 litres is quite a lot.

IF you drained it properly and changed the filter, you probably need to add another half a litre. Probably.

Try dipping and wiping the dipstick 9-10 times without pushing it fully home or until it comes back clean. Then do one where it does go all the way home and take the reading from that.


If its only done 65K miles, it shouldn't need a rebuild and it should have good compression. I tested my 56K engine last week and got near perfect results.

http://sxoc.com/vbb/showthread.php?5...est&highlight=

A rebuild to replace the piston rings, inlet valves and stem seals can be done for around £250 for the parts if you do it yourself, most of which is the cost of an OEM gasket set. If you pay someone to do it, maybe £750 ?

If it needs a rebore, pistons, main and big end bearing shells, the head skimming or if you go with aftermarket stuff for a big power build then a lot more money.

There is quite an active scene around East Anglia. Contact slip'n'slide (Matt) as he's the area rep and there is some good knowledge of 200s in the club.

There is a club stand at the show at Helmingham Hall too on the 7th August that I will be at.

[s13adam]

I didn't change the filter as it's out 2 months old and was done before I purchased it

Looking at the dip stick it looks like it could still be a bit high, I'll go for a drive and give it a good run

I wonder if anyone in easy Anglia would want to help me fit my coilovers? Beer money available as well as biscuits.......

Thanks for the help so far gents, it's much appreciated

[green_rs13]

i always used to take the dipstick out, clean it off and leave it out over night to check the oil level.

[Jonny Wilkinson]

There is a guide to fitting posted by me. Do a search. Its not hard once you have the guide.
3 ltrs is about right without a filter change but I'd have swapped it anyway.

Sent from my XT1032 using Tapatalk

[Jonny Wilkinson]

i always used to take the dipstick out, clean it off and leave it out over night to check the oil level.

Trouble is you can get a bubble of oil in the tube that won't drain overnight.

Sent from my XT1032 using Tapatalk

[Dastardly]

You need to replace the oil filter anyway because you may be using a different oil to what the previous owner used so a bit of mixing might be going on. Also I had to rebuild by CA at 26K miles as it had low compression from lack of use and rings had stuck together so don't assume it's OK because it's done low miles.

[Jonny Wilkinson]

Sometimes rings will come unstuck after a little spirited use but I get your point, D

Sent from my XT1032 using Tapatalk

[s13adam]

I always drive it spirited so we shall see what happens

Could the timing of the engine have a thing to do with it? It had a cambelt very recently but I know the garage and they don't have the best reputation and they were one that did the oil change a few months ago before I bought the car

[Dastardly]

Well if the timings off then it will misfire but it won't make the compression low.

[Haywes]

The way I find I get the most accurate reading with the dipstick is to remove it, clean it, put it back in about 80% of the way, remove it and clean it another 2 times, then put it all the way down in and leave it a second before removing to check. This usually comes up pretty clean with a fairly clear level as it cleans out the tube.

[pointz]

i always used to take the dipstick out, clean it off and leave it out over night to check the oil level.

Il be honest i find the best time to check my oil is 1st thing in the morning although i dont leave my dipstick out overnight!

[skyshack]

Compression test should be done with fully charged battery. If compression results reduce successively over test go back and do the first one again. If that doesn't read what it did first time the battery isn't up to it and needs charging.

[s13adam]

A good point

The tests got weaker as I got to the last cylinder

I'll start with the last one first when I do it tomorrow, I'll also do it from cold with the throttle open

[Jonny Wilkinson]

Stick a jumper pack on it. You need the battery power to get consistent results.

Sent from my XT1032 using Tapatalk

[s13adam]

Just to update this a bit

I haven't got round to doing another compression test yet but the car is still smoking a bit

It's appears to happen when I'm on a hill, even the slightest gradient it kicks out blue smoke and it stinks

I ran it for 20 mins at home the day I changed the oil and it was good as gold, presumably the oil level being too high and at an angle would make it smoke?

Thanks to everyone for their input as well, it is much appreciated

Adam