Just bought a 96 940 - First Jobs

[Laird Scooby]

Just to clarify on the flame trap, the nipple as Volvo call it is still a flame trap, with or without the gauze-type plastic mesh inside.

I've known huge flame traps that have also been called spark arrestors and they've been about a foot in diameter by about 8-10" long - usually mounted as part of the air intake system. I've also known small "universal type" fuel filters to be called flame traps if that is what they've been included in the system for.

Anyway, if Volvo hadn't fitted the flametrap/Y-piece/nipple or whatever you want to call it so close to the oil separator it wouldn't clog so easily, filter/gauze/mesh inside or not, turbo or not.

On some of the last 740s, they moved the flametrap above the inlet manifld which is what gave me the idea to modify my last 740 that way and it works - keeps them much cleaner and clearer!

[vickyg]

Brookhouse can get the hose from Sweden or I could fashion my own from 16mm bore heater/oil pipe in the meantime...also 10% of the price!

[vickyg]

Well now I'm miserable. Fixed up all the breather pipes today, new Y etc. Start the car and it runs lovely, not a drop of smoke. Well pleased. I leave it to tick over while I tidy up and after a few mins it shows signs of stalling. I apply some revs and it starts smoking again. Check the unions and everything seems fine. You can blow through the breather pipes so they're good now. Bear in mind when I bought it the woman had been running it with no washer on the oil filler cap. I think she was clueless and suspect someone 'helpfully' did this as a 'solution'. Now I'm a little stumped as to what next, other than do the same which does not sit well with me.

[Laird Scooby]

Originally Posted by vickyg

Well now I'm miserable. Fixed up all the breather pipes today, new Y etc. Start the car and it runs lovely, not a drop of smoke. Well pleased. I leave it to tick over while I tidy up and after a few mins it shows signs of stalling. I apply some revs and it starts smoking again. Check the unions and everything seems fine. You can blow through the breather pipes so they're good now. Bear in mind when I bought it the woman had been running it with no washer on the oil filler cap. I think she was clueless and suspect someone 'helpfully' did this as a 'solution'. Now I'm a little stumped as to what next, other than do the same which does not sit well with me.

That's a bummer! Did you say it's a B200F? Does it tick over happily once hot? Did you clean the AICV and throttle body as part of the cleaning process?

Also did you do like i suggested and add some Carlube ATF-U to the engine oil?

[ovlov236]

Originally Posted by vickyg

Well now I'm miserable. Fixed up all the breather pipes today, new Y etc. Start the car and it runs lovely, not a drop of smoke. Well pleased. I leave it to tick over while I tidy up and after a few mins it shows signs of stalling. I apply some revs and it starts smoking again. Check the unions and everything seems fine. You can blow through the breather pipes so they're good now. Bear in mind when I bought it the woman had been running it with no washer on the oil filler cap. I think she was clueless and suspect someone 'helpfully' did this as a 'solution'. Now I'm a little stumped as to what next, other than do the same which does not sit well with me.

Might Be A Idea To Get A compression Meter To Test Healthy Engine Or Not ?

[vickyg]

B200FT. I did not let it get hot as to be honest as clearly something is still wrong. I could let it get hot with the oil cap off I guess. Did not add anything to the oil yet, I want to establish and hoped for a major improvement and then drive it to a garage for the cambelt and full oil service.

Did not do anything with throttle or AICV. I tend to tamper with one variable at a time until I know what fixes. It was running lovely when purchased, but of course the hoses were clogged and oil cap off. I have no changed the oil trap box. I could do that but other advice was very unlikely to be the issue and it does 'breathe' i.e. air blows through.

[vickyg]

Originally Posted by Laird Scooby

That's a bummer! Did you say it's a B200F? Does it tick over happily once hot? Did you clean the AICV and throttle body as part of the cleaning process?

Also did you do like i suggested and add some Carlube ATF-U to the engine oil?

If AICV or throttle body an issue would stalling on ticked not have manifested from the outset i.e. before I fitted new oil cap seal etc.?

[Laird Scooby]

Originally Posted by vickyg

If AICV or throttle body an issue would stalling on ticked not have manifested from the outset i.e. before I fitted new oil cap seal etc.?

Not necessarily, if they're partially blocked that may have matched the blockages in the PCV system so the ECU would have altered the trims to suit. Now it's still trying to run on those same trims.

Originally Posted by vickyg

B200FT. I did not let it get hot as to be honest as clearly something is still wrong. I could let it get hot with the oil cap off I guess. Did not add anything to the oil yet, I want to establish and hoped for a major improvement and then drive it to a garage for the cambelt and full oil service.

Did not do anything with throttle or AICV. I tend to tamper with one variable at a time until I know what fixes. It was running lovely when purchased, but of course the hoses were clogged and oil cap off. I have no changed the oil trap box. I could do that but other advice was very unlikely to be the issue and it does 'breathe' i.e. air blows through.

Something is wrong but if my suspicions are correct, not as wrong as you fear! Pull fuse #1, clean the AICV by giving a good squirt of carb cleaner in the direction of air flow, move on to cleaning the inside of the throttle body, opening the throttle by hand so you can squirt carb cleaner everywhere inside it, periodically pausing to give the AICV another squirt before continuing.

WHen the throttle body is clean and the AICV has had a few good squirts a few minuts apart, refit the hoses etc and refit fuse #1 and start it up. It mat need some throttle because of the carb cleaner etc in the inlet manifold.

Let it idle (or better still, drive it until it warms up and see how it idles then - should be ok, even if it is still a bit smoky.

Do you know what brand of engine oil is currently in there?

[vickyg]

No idea on oil. Old and cheap I would imagine. This is a neglected car. I'll probably go fully synthetic.

[Laird Scooby]

Originally Posted by vickyg

No idea on oil. Old and cheap I would imagine. This is a neglected car. I'll probably go fully synthetic.

Don't go full synthetic, nothing to be gained and could do more harm than good in an engine designed for semi-synthetic.

The reason i ask about the oil is a few years back i had a bad experience with Triple QX 10W40 semi-synth. After using it for some years without a problem, it suddenly made 3 different engines smoky overnight. I'd done oil and filter changes the previous days and then the engines started smoking, were hard to start and so on.

Turned out they were using recycled oil as part of their blend and until then i'd been lucky and got oil that was more fresh than recycled, this was more recycled than fresh.
A bit of research online revealed i wasn't the only one and many others had similar problems. Whether they've changed it back to completely fresh oil or not i don't know but i won't be chancing it again!

From everything you say, i wouldn't be at all surprised to learn that is what's in there at the moment. I'd strongly suggest you do your own oil/filter change (it's not unknown for garages to simply wipe the filter over to make it look new again! ) as i suggested above adding some ATF-U to the oil for a few days before the change than afterwards subsitute a minimum of 0.5L of engine oil (max 1L) with ATF-U then top up with a good 10W40 semi-synth and use the car.

This will help revive the oil seals that will have been dried out by the old dodgy oil, clean the engine internally and generally improve things for you.
If you dipped either of my engines you'd find some ATF-U if you had it analysed, one engine has hydraulic tappets and is known to produce clatter when cold - mine doesn't! Also the emissions have been cleaner year on year in both cars with improved economy and performance.
As a result of the Triple QX in my 760, i had a weepy crank rear oil seal. Since adding 1L of ATF-U to the 5L of Gulf-Tec 10W40 Semi-synth, that has cleared up.

After doing the oil/filter change and starting up to check for leaks, switch off and pull fuse #1 again while you go and get cleaned up, have a brew and put your tools away. Then refit fuse #1 and take it for a test drive.
Might be a bit of smoke now and again (particularly the over-run) but this should clear with use. When it's next due an oil/filter change, if the oil that comes out is seriously dirty, use about 1L of ATF-U as part of the refill, if it's cleaner than you expect, just use 0.5L instead.

If there isn't a fairly quick improvement after doing the oil change this way, it might be time to do as Louise suggested and get a compression test on it.