enough is enough Car fumes ?

[johngosnell]

my last major show on Saturday prior to winter and I cannot deal with the fumes coming into the car any more. It was so bad if I had to do a long drive it would have killed me. The Exhaust is a SS installation and is sound, the onlyy thing I can imagine is the heater matrix having seals to the body missing. Firstly any other suggestions would be very welcome, secondly I have been on the SNG Barratt web site and it looks as if there is nothing available. So suggestions would be of great help.


Best wishes John


1B1257BW

1972 Rover P6

[Jose]

is the bonnet seal at the rear of the bonnet in front of the Vent Scuttle in good condition?

is the Wipers Cable Grommet sealing the cable at the point where it crosses through the firewall ?

there are 2 access panels at the front of the transmission tunnel, one on each side. Are those sealed with caulking and screws?

suspect: the gaskets at the manifolds to cylnder head and the onion seals at the bottom of each manifold to each down pipe.

As to the foam seals for the Heater Box and Fan, you might need to manufacture new ones with dense foam sheets.

[cass3958]

I think you need to find what is causing the fumes before you start trying to find how they are getting in to the cab. I have holes in my bulkhead where grommets are missing or where the cables run but I do not have any fumes from the engine which might migrate in to the cab.
I know we have had this conversation before but is it a Petrol smell? A burnt oil smell? An exhaust fume smell? Burning rubber smell?
One we can establish the cause of the fumes we can eliminate the cause and then there will be no need to hermetically seal the cab from the engine bay.
There are two crankcase breather tubes at the back of the rocker covers which lead down to the block between the gearbox and the engine. These are very fine brass tubes which being fine could get blocked which in turn would stop the rocker covers venting in to the block. These tubes can get crushed against the bulkhead when putting your engine in so I would start with these. I have attached two photos of the tubes on the back of the engine.

[NigelW]

Those tubes are oil feeds to the camshafts.

[Jose]

yes Nigel, I was trying to figure those tubes too.

[cass3958]

My mistake Sorry. Any other suggestions as to where these fumes could be coming from?

[Jose]

if the rear bonnet seal is not sealing, and the fresh air scuttle vent is open, it is the most probable place.

Air and engine fumes are being sucked into the cabin via the fresh air vent if the Fan is on, or if the car is moving.

the same thing happens in my Ford Aerostar minivan if I turn the VENT switch to ON. But if I turn the switch to RECIRCULATE, the fumes smell dissapears.

Another possibility is the engine breather at the front of the cylinder head behind the coil. If the mesh filter is not clean and is clogged, those fumes are not escaping via the tube and into the air filter to be burned at the intake.

[johngosnell]

Firstly thank you all again for the reply's, with regard to the seal on the bulk head in front of the fresh air scuttle the seal was newly fitted last year after we talked about the same issues. I have to be honest and the smells are more like exhaust smells but including general engine smells, my son is on holidays this week so I hope he will come over to start to investigate. Has anybody got any pictures of the panels mentioned by the engine tunnel, the other thing we will be looking at is the engine breather on the front chest of the engine that feeds into the air filter system. Do I understand that this is the only breather.

Regards John

1B1257BW
11972 Rover P6

[cass3958]

John I do not think that sealing the engine compartment from the cab will solve the problem until you find where the fumes are coming from on or around the engine first.
There are so many small holes in the bulkhead from where the wiring loom goes through to the vacuum pipes for the heating. Then you have all the holes behind the heater matrix and the inspection plates on the gearbox tunnel. All these should be sealed with rubber bungs but these deteriorate over time or fall out. What I am trying to say is we all have holes from the engine compartment to the cab but we all don't have the smells you are getting so the origin of the smell needs to be located and repaired first.
As you said there is just the one breather from the front of the engine which has a pipe that runs up to the air filter housing. As Jose said behind this housing on the front of the engine is a gauze which can get blocked over time and if the gases cannot be vented out of the engine vis the air intake and back out of the exhaust you will possibly be getting some escaping into the engine compartment.
Other than that I would check the exhaust is sealed correctly at the top and bottom of the manifold and that the exhaust joints are all sound.
I would check for oil leaks which might be dripping onto something hot and creating a smell.
if you have painted the engine recently do you think it could be the paint getting hot and sending off a smell which might go away in time with more use?
Clutches can smell if binding or new but this is a very distinctive smell which is the same as if your brakes were binding. Has your car has been converted to a hand clutch so if its a clutch smell it might need adjusting. You would not get the same smell from an Auto box.

[Jose]

the transmission tunnel inspection /access panels are at the front as you near the bulkhead.

raise the carpeting and you will see they are sealed with some elastic caulking sealant and phillips screws.

remove all the screws and pull the panel to reveal the transmission sides.

you can test if they are well sealed by spraying water from the outside.

exhaust smell can only be the exhaust. Also check the rubber seal between the air filter and the carbs intake where the air filter goes into the aluminium intake.

the join between the manifolds and the down pipes is exactly in front of the passenger side transmission access panel in RHD cars. Bad onion or "donut" seals there will allow exhaust to escape.

most manifolds have only two studs each tightening the downpipe to it. But there should be 4 studs at each manifold to down pipe join for the best possible seal.