13 years since an MOT

[Ian21401]

Originally Posted by fredmd3

Hey everyone!!

Then the last job before MOT time will be the rear exhaust. The trouble I'm having here is about mounting points. I ordered one online and the mounting points were right at the end of the muffler, not in the middle as they are on the car. I'm struggling to find one with the correct mounting points; what should I do?
Attachment 135914
Attachment 135915
Thanks very much
Fred

Hello Fred. Well done.
I suggest that you check the rear subframe to ascertain where the hanging brackets are located.
I have a 1992 940. My last two Volvo exhaust kits have included a back silencer box with the hanging brackets at the very back end as per your image. (part no. VO 31392963 ) and tail pipe ( VO 31372174. )
The “fitting kit” is sold separately and consists of two silencer bands and four rubber hangers. My car does not have hanging brackets at the extreme rear of the rear subframe. Mine are fixed further forward on the rear subframe and are not exactly opposite each other. The main dealer’s database for my car indicates that those brackets are exactly opposite each other and the fitting kit (VO 31372144 ) is required. I queried this and was informed that there is another fitting kit listed (VO 31372148 ) for earlier models. The dealer ordered in that kit and it was found to contain a rear exhaust band with offset hanging brackets which match the brackets on my car’s subframe.
There is also a “Klarius” brand bracket available which has the offset brackets ( part no. VOP39AK 430235 ) which may be available via your local motor factor.

[Laird Scooby]

Originally Posted by fredmd3

Then the last job before MOT time will be the rear exhaust. The trouble I'm having here is about mounting points. I ordered one online and the mounting points were right at the end of the muffler, not in the middle as they are on the car. I'm struggling to find one with the correct mounting points; what should I do?
Attachment 135914
Attachment 135915
Thanks very much
Fred

Been thinking on this, are you sure you have a 1989 car? If it's a 1988 it would might have different mountings and/or did you order the correct year back box? Also have you got the tailpipe for it?

An engine code would be helpful and the model year (MY) too, you'll need to decode the VIN for that :

https://www.volvoclub.org.uk/vin_700.shtml

Having had a few 1988/89 740s, i know there is a changeover point on exhausts somewhere in that timeframe.

[fredmd3]

Hi everyone,

Been a while since my last update but I'm absolutely pulling my hair out over the problem I currently have.

I've been working on the car on and off over the last year with a very helpful friend who can fix most things but this one has us stumped and neither of us have any experience of Volvos. Since the last update we got the car to another MOT which unsurprisingly it failed but it did give us a great to-do list which is now all done....we think!

That included sorting some rust underneath which I hadn't spotted, replacing the handbrake cable, sorting the numberplate light and a couple of other lights with some genius wiring fixes and replacing the horn. So all ready for another MOT...but....it wont run when hot!

I've never actually given the spec of the engine during this thread - it's a B230E.

Starts, idles and revs when cold absolutely fine. After a couple of mins of idling the engine warms up a little of course. Idle is still not too bad but as soon as I add some throttle it dies. I can feather the power to get it through that area of dying up to higher RPM and at that point it sounds ok again. So I'm certain the issue is of it running too rich when hot. Obviously starts rich when cold but doesn't change the mixture when it warms up and is still dumping too much fuel in to run when hot. This wasn't an issue a few weeks ago at the last MOT, became an intermittent problem and now it's every time.

I noticed the temperature gauge on the dash wasn't working so changed the coolant sensor (circled in the image attached) but that hasn't changed the performance of the engine or even got the gauge working! The resistance of the old sensor wasn't working as it should but the new one is. Is there another temperature sensor I need to change?

Could it be something to do with the warm-up regulator?

Keep feeling like I'm at the finish line with this project but then keep finding another hurdle to overcome. I'm at the point where I'd love for an expert in Volvos to come out to the car (near Guildford if this tickles anyones fancy) and apply their magic to it!

Thanks for any help or advice,
Fred

[Laird Scooby]

Originally Posted by fredmd3

Hi everyone,

Been a while since my last update but I'm absolutely pulling my hair out over the problem I currently have.

I've been working on the car on and off over the last year with a very helpful friend who can fix most things but this one has us stumped and neither of us have any experience of Volvos. Since the last update we got the car to another MOT which unsurprisingly it failed but it did give us a great to-do list which is now all done....we think!

That included sorting some rust underneath which I hadn't spotted, replacing the handbrake cable, sorting the numberplate light and a couple of other lights with some genius wiring fixes and replacing the horn. So all ready for another MOT...but....it wont run when hot!

I've never actually given the spec of the engine during this thread - it's a B230E.

Starts, idles and revs when cold absolutely fine. After a couple of mins of idling the engine warms up a little of course. Idle is still not too bad but as soon as I add some throttle it dies. I can feather the power to get it through that area of dying up to higher RPM and at that point it sounds ok again. So I'm certain the issue is of it running too rich when hot. Obviously starts rich when cold but doesn't change the mixture when it warms up and is still dumping too much fuel in to run when hot. This wasn't an issue a few weeks ago at the last MOT, became an intermittent problem and now it's every time.

I noticed the temperature gauge on the dash wasn't working so changed the coolant sensor (circled in the image attached) but that hasn't changed the performance of the engine or even got the gauge working! The resistance of the old sensor wasn't working as it should but the new one is. Is there another temperature sensor I need to change?

Could it be something to do with the warm-up regulator?

Keep feeling like I'm at the finish line with this project but then keep finding another hurdle to overcome. I'm at the point where I'd love for an expert in Volvos to come out to the car (near Guildford if this tickles anyones fancy) and apply their magic to it!

Thanks for any help or advice,
Fred

It actually sounds as if it's going lean once it warms up. The only temp sensor as far as i remember is the one for the temp gauge which you've changed - chances are the gauge itself no longer works.

Check all the inlet manifold nuts for tightness and if all good, spray some WD40 around the join between inlet manifold and head while running - any leaks will alter the engine tone slightly.
Also check the rubber "sock" between the throttle body and fuel distributor for security on both ends and for pinholes, splits and similar as an air leak here will give strange symptoms not unlike you have.

Ideally you need an exhaust gas analyser to see what it's doing when it wants to die, it's not really good enough to guess. However if you want to make an "edumacated guess", when it warms up and doesn't want to rev, spray some WD40 into the air intake while trying to rev it - if it's going lean the WD will let it pick up somewhat. If it's going rich, it'll make it worse.

[fredmd3]

Thanks Dave, I’ll certainly try what you’ve suggested next time I go to the car.

What I don’t understand is why it changes as it warms up. Initially it’s ok on idling and revving but then gets worse when it’s warm to the point the car won’t actually move, just stall on throttle (which is why I thought too rich). What actually governs the mixture as the engine warms up?

[Laird Scooby]

Originally Posted by fredmd3

Thanks Dave, I’ll certainly try what you’ve suggested next time I go to the car.

What I don’t understand is why it changes as it warms up. Initially it’s ok on idling and revving but then gets worse when it’s warm to the point the car won’t actually move, just stall on throttle (which is why I thought too rich). What actually governs the mixture as the engine warms up?

That would be the warm up regulator that makes the mixture richer while it warms up - i wonder if perhaps in the past it was stuck in warm-up mode and the CO mixture was adjusted for an MoT? That would cause it to go lean now, especially if the thermostat has gone weak and it's taking too long to warm up and/or not warming up properly - the warm-up regulator (as far as i remember) is electrically heated so the engine relies on the coolant 'stat doing its job properly.
Some K-Jets also had a cold start injector, electrically operated but this only really works on the first few seconds of running so whether that's working or not, we can probably discount that as the cause of the problem.

Have you got any other method of checking the engine temperature, for example an infra red thermometer?

[fredmd3]

I could probably borrow an infrared camera from work.

I should have posted the emissions levels from the MOT I had done in Nov 22 (when it was running adequately enough to get there). This is showing it to be too rich, correct?

[Laird Scooby]

Originally Posted by fredmd3

I could probably borrow an infrared camera from work.

I should have posted the emissions levels from the MOT I had done in Nov 22 (when it was running adequately enough to get there). This is showing it to be too rich, correct?

Yes, that is running rich but not so rich that it will flood unless it's going significantly richer when you push the throttle.

Have you renewed the air filter element at all? Also is the corrugated aluminium hose still connected to the air filter inlet? If so, disconnect that as a diagnostic task and also to reduce emissions but renew the air filter if you haven't already.

[AllHailKingVolvo]

Would love to know if there’s an update on this! I’ve been following the thread with interest.

[Foeux]

'Ello Fred. I too am a Fred.

I am really glad you are breathing new life into a succulent old slab of Swedish steel.

With everyone fretting about cambelts, based on my sample size of one, WHAT A LOAD OF RUBBISH!

For fun, I 'checked' how strong an outgoing cambelt of maybe 10yr old or more was.

On one end of the cambelt was a V8 Range Rover classic, on the other was my Volvo.

It was in gear with the hand brake on and chocked. The range rover dragged the Volvo a good way before the cambelt eventually snapped due to a shock load. The chock (a 28lb sledge hammer) jammed against a raised drain cover which made the Volvo jump in the air over the obstacle which snapped the belt.

My chum and I were very pleased with our gentleman-science and also thrilled at how strong the cambelt was.