(Home) Smoking in reverse

When driven forwards my Townie does not emit any smoke from the exhaust, but when in reverse it smokes like mad, so much so that it nearly disappears in the cloud, but as i say it only happens in reverse. Any ideas anyone?

- (#6132) Steve Taylor, 14 Nov 02

Steve,
This IS a strange one. The engine, of course, still runs in the same direction when reverse is selected so, any malfunction, of the engine, should appear when in the forward gears. You are, obviously, not going very fast in reverse and I assume that the smoke does not appear when you are going slowly in, say, first gear. Is the "flexing of the transmission, ie, the propshaft turning in reverse and applying opposite torque, causing some interference with a faulty exhaust joint or, in some mysterious way, boosting the fuel (Is it diesel ?). If it's exhaust smoke, might you not have noticed it when pulling away in a forward gear ? I looked forward to some diagnosis from one of our experts.

- (#6133) John Davis, 14 Nov 02

if it's a diesel and the smoke is blue, i'd look at the breather on top of the head, and the return line from the turbo to the sump. i've recently had a problem with the engine being pressurised because of a blocked breather, causing smoke intermittently at odd times. remember that the engine "torques" the opposite way in reverse, this could be sloshing oil about somewhere.

if the smoke is black, that would mean excess fuel- possible wear in the injection pump?

and remember that we tend to (or i do anyway) stand on the throttle a bit more in reverse- this will show up oil burning through the turbo and valve stem seals, and coking of the intake manifold more readily than blipping the throttle.

hth

- (#6134) david miller, 15 Nov 02

When the car is stationary it does not smoke when on a low tickover or at increased rev's, driven forward it dosen't smoke, it only smokes in reverse, and it seems to be a blue smoke which suggests that oil is being burnt somewhere. It is a diesel. I will check the breather and the return line from the turbo on Saturday.
Thanks for the help

Steve

- (#6135) Steve Taylor, 15 Nov 02