smoking engine advice

Hi all recently we started a series 3 pickup project and the final hurdle before the mot is the smoke problem, it driving us mad!

So far we tried the pump timing and this sadly made verry little difference.

At the weekend white setting up the butterfly valve for the brake servo I noticed the inlet manifold was full of oil. It was coming from the rocker cover breather pipe as it was linked into the butterfly valve housing. With the pipe removed and the engine running it was blowing oil mist so it has blown it into the inlet manifold. Can I disconnect this from the butterfly valve and blank it off? Or is it an important bit. I was thinking I could run a breather pipe leading to the bottom of the engine and blank off the butterfly valve pipe to keep the inlet manifold oil free.

Should oil spray out of the breather pipe on the rocker cover lid?

If that was the problem will it take a fair while for the engine to clear itself out and the smoke to reduce?

Many thanks for any advice - once we sort the smoke problem we are nearly there

id say engine was worn and needs a rebuild to make right

Oh dear was hoping not to hear that! Is that a big job? Could valve stem seals or timing cause theese symptoms?

Would a compression check show if this is needed as im not very knowledgeable on engine rebuilding and not very well off so funds are a bit tight too.

Is there any things I could try before this?

Many thanks tom.

you could try a compression check ,heavy breathing will be caused by poor bores and rings ,something the engines prone to especially after 30 years,200tdi is a good fix

Hmm been wondering about the 200 tdi, is it hard to fit for an enthusiastic diy learner?

Would a compression test tell me I'd it needed rebuilding?

first off does the smoke clear after giving the engine a good workout at full temperature ??

is the smoke white/grey or blue/black ??

my old 2.25 diesel smoked like a trooper on 80 a day until you got it up to temperature

what year is your S3 ? i think it's pre 1976 and the test is only a visual one, so if you can get the smoke to clear once up to temperature then make sure the engine is still hot when the test is conducted

NiteMare said:

first off does the smoke clear after giving the engine a good workout at full temperature ??

is the smoke white/grey or blue/black ??

my old 2.25 diesel smoked like a trooper on 80 a day until you got it up to temperature

what year is your S3 ? i think it's pre 1976 and the test is only a visual one, so if you can get the smoke to clear once up to temperature then make sure the engine is still hot when the test is conducted

Click to expand...

Cheers nightmare!

Part of the problem is not been able to take it for a run to get it up to propper running temperature to get a good idea and to try clear it out and assess it better.

It is bad even next door complained when he had his windows open on a still summers day.

I would say the smoke varies between blue/white/grey but the oil and water is clean so not sure?

If it was the breather pipe blowing oil mist into the inlet manifold and it has mucked up the engine/exhaust etc would it need a really good run to clear it out?

Cheers for the helpful replies!

reet theres 2 major things with the smoke

the most common problem with the 10j diesel engine is the head gasket goes between the piston bores and the cam rocker linkage rod hole but doesnt effect the water ports causing back pressure to force oil into the pipe at the top into the manifold

id personally get a complete gasket set for the head £15 ish then while the head is off id change the stem oil seals and inlet n exhaust gasket aswell while i was at it flush the inlet manifold out clean with petrol to remove all oil from the bugger ( getting oil in there can eventually get the engine running at full pelt unstopable till it dies )

in a moment of investigation i noticed that on the 12j engine all the stem oil seals are spring loaded ( little spring round them ) unlike the 10j that only has them on either the inlet or outlet valves id leave the sprung ones on the valves and replace the unsprung ones with the new sprung ones out of the kit

as for the pump tweak thing not working much id lay a good bet on the skew gear being worn out underneith it that drives the diesel pump and the oil pump below that

i hope its not the skew gear as theyre not only heckspensive theyre a complete pig to replace and set up right but more often than not its the head gasket and valve stem oil seals

just remember if you do the head gasket the head bolt torque setting is 90lb/ft and all the tappets need to be set at 10 thou"

ok it sounds like most of your problem is unburnt fuel and maybe a little oil weeping in after being sat idle, when i took my 2.25d for it's mot you couldn't see the road behind me for unburnt fuel smoke (this was in the middle of Brum lol) but by the time i was halfway there it started to clear up nicely (4 mile journey tops) getting the engine and exhaust nice and hot to help create full combustion and burn the crud out of the exhaust, i kept the engine running whilst it waited for the mot to keep the temperature in it and the emmisions (visual) passed just fine

every morning after that it took 1/2 a mile or so to clear up properly but once up to temperature the exhaust was nice and clear

just trying to run the engine up out the back of your house will struggle to get the temperature up, the engine needs working under load and revving quite hard to get it hot

if there's no oil in the water and vice versa then ignore that as a red herring

you could always book it in for mot and take it an hour early to the test and then decide to continue or cancel the test, this way you get to run the engine properly (this is not behaving strictly to the letter of the law but is one way around things, if stopped on the way you can always use the excuse that you're going early in case you need to fix anything on the way tools in the tub)

messing about trying to adjust the injection pump will only match it to either the crank position OR the cam position which means it still won't run correctly unless you fit a new timing chain and then time it all up correctly, final expenses with the fuelling is going to be recon injectors and possibly recon injection pump (expensive), we have no idea of the state of the head or bores and neither do you so you could have wear or cracks which will both lose compression, a proper rebuild could work out expensive as by the time the bores/rings are worn you would generally be looking at the bottom end as well for new shells and a possible regrind

don't lose heart as these old engines will run in very poor condition but just not efficiently or with full power once worn, individual spares for them can be pretty cheap, unknown secondhand units are worth very little more than scrap value (i've sold three for no more than 25quid each (scrap value at the time) and occaisionally folks give them away just to get shot of them (i really wouldn't weigh one in as eventually there'll be no secondhand spares)

Hi johnny curt 1 that's sounds exactly the advice we needed!

I'll get a head gasket ordered and a timing chain kit. We already have a valve stem seal kit, but they don't have the little springs on them. Do thsee sound like the wrong ones?

When I undid the rocker cover breather pipe and saw all the oil I wondered if this could have caused a runaway engine?

When the pump is turned if does change engine tone but doesn't affect the smoke, this sounds promising as it is changing the fuel timing by the sound of it.

We tried a set of second hand fully working injectors and the problem didn't change so we don't think it's them either.

I'll get a head gasket set and a timing chain ordered and look at following your advice.

We don't want to give up on this engine as we like to keep it originally and no doubt the pride in rebuilding and repairing it will be priceless !!!

Thanks again johnny curt 1 and nightmare your info is much appreciated, and sorry for all the questions. I'll keep the thread updated on our progressionn

toms3 said:

Hi johnny curt 1 that's sounds exactly the advice we needed!

I'll get a head gasket ordered and a timing chain kit. We already have a valve stem seal kit, but they don't have the little springs on them. Do thsee sound like the wrong ones?

When I undid the rocker cover breather pipe and saw all the oil I wondered if this could have caused a runaway engine?

When the pump is turned if does change engine tone but doesn't affect the smoke, this sounds promising as it is changing the fuel timing by the sound of it.

We tried a set of second hand fully working injectors and the problem didn't change so we don't think it's them either.

I'll get a head gasket set and a timing chain ordered and look at following your advice.

We don't want to give up on this engine as we like to keep it originally and no doubt the pride in rebuilding and repairing it will be priceless !!!

Thanks again johnny curt 1 and nightmare your info is much appreciated, and sorry for all the questions. I'll keep the thread updated on our progressionn

Click to expand...

dont waste your money get a tdi fitted in or that one rebored and done properly ,timing chain fitting isnt a novice job,spring around ex valve stem seals make no difference

When fitting timing chain is it just a case of getting cam top dead centre and crank top dead centre then fit chain and take up slack on tensioner? I've not fitted one before done couple of belts on single cam 8 valve petrol engines but never a chain ?? We were going to attempt chain on it next weekend if we fit with both tdc and turn engine over by hand and no contact is made fine tune it on pump or am I miles off?

d90matt said:

When fitting timing chain is it just a case of getting cam top dead centre and crank top dead centre then fit chain and take up slack on tensioner? I've not fitted one before done couple of belts on single cam 8 valve petrol engines but never a chain ?? We were going to attempt chain on it next weekend if we fit with both tdc and turn engine over by hand and no contact is made fine tune it on pump or am I miles off?

Click to expand...

no they are timed at exhaust peak no1,cam needs setting using a dti to find exact exhaust peak by marking cam sprocket before peak and at the same poisition after and measuring halfway between the 2 marks to get exact peak then fitting chain using vernier slots on sprocket to get right tension and positioning

Well we was hoping to keep this engine as unfortunately it it's too expensive to buy a new one and fitting. We would like to have a go at repairing this one and hopefully learn lots on the way. It's only done 122k and been in a barn for 4 years so hopefully it's not worn out but just needs new gaskets, seals, service and timing. Hopefully the mileage is genuine considering its condition so worth a go on repair? The parts are cheap, we are willing to do it and learn from it so surely worth a shot? When we take head off and it looks like scored/stained bores then we will look at that.

toms3 said:

Well we was hoping to keep this engine as unfortunately it it's too expensive to buy a new one and fitting. We would like to have a go at repairing this one and hopefully learn lots on the way. It's only done 122k and been in a barn for 4 years so hopefully it's not worn out but just needs new gaskets, seals, service and timing. Hopefully the mileage is genuine considering its condition so worth a go on repair? The parts are cheap, we are willing to do it and learn from it so surely worth a shot? When we take head off and it looks like scored/stained bores then we will look at that.

Click to expand...

well check bores with a proper comparator, anything more than a few thou is worn out and piston and bores are the engine ,been stood might be the issue you dont need much rust to effect ring bore contact which causes pressurisation /oil loss /smoke

jamesmartin said:

no they are timed at exhaust peak no1,cam needs setting using a dti to find exact exhaust peak by marking cam sprocket before peak and at the same poisition after and measuring halfway between the 2 marks to get exact peak then fitting chain using vernier slots on sprocket to get right tension and positioning

Click to expand...

Yea does sound bit complex that ! Bugger was hoping it would be straight forward job!

Would a 2.5na engine fit straight in?

jamesmartin said:

well check bores with a proper comparator, anything more than a few thou is worn out and piston and bores are the engine ,been stood might be the issue you dont need much rust to effect ring bore contact which causes pressurisation /oil loss /smoke

Click to expand...

Cheers jamesmartin. so can been stood easily cause some rusting in the bores? Hope that's not happened!

If they look ok visually is there a way of measuring them for wear?

if it's possible what sort of costs are involved in rebore, piston and rings?

Thanks again!

easily after a few months let alone 4 years though depends on its circumstances ,before removing head drain block by removing brass bung on exhaust side of engine half way on block,you can feel very worn engine 1 cm down bore on passenger side ,re
bore usually £120 plus vat pistons £20 each ish ,bores are bored and honed to suit new pistons ,you cant just fit new pistons in old bores