Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Petrol smell and drip from engine

Afternoon all.. The last couple of times I've been out in my car I've noticed a petrol smell but couldn't pin down where it was coming from but today when I parked up I noticed a small drip from the bottom of the engine and some fluid on the case just below the airfilter. It smells like petrol but I guess it could be oil.

|Are there any common causes that I should look out for before I book a trip to the garage?

Thanks

It will evaporate quickly if it is fuel unlike oil which will remain as a guide.

A picture will help others with the same engine diagnose it if you can get one posted. That is if it's the Plus 4 you are talking about as you have posted in the M3W thread !

fuel dripping from a hot engine is pretty dangerous…

Thanks both. It is the 3 Wheeler I am talking about not the Plus 4. Not much see in picture apart from the drip on the ground. I stupidly wiped the liquid of the top of the crank case(?) before taking a closer look at it.

I think it must be oil to still be on the drive, is the air cleaner housing dry to the touch on the lower edge I wonder.. I'm not familiar with them but is it a wet filter I'm thinking..

Sometimes leaking fuel will dissolve some of the engine crud/dirt and then not evaporate fully leaving a drip. However, looking at the cleanliness of your engine, I doubt there's much muck on it!

Assuming its petrol remove the plastic cover/fan support from the top of the engine, disconnect fan electric connection under the bonnet first, don't lose spacers under bolts and use loctite on threads when replacing bolts.
Turn ignition on to run the fuel pump and pressurise fuel system, turn ignition off and check the fuel hose and connectors to the injectors for leaks/weeping.
If its oil could be front crank seal or starting the engine after wet sumping and blowing some oil out of the breather/ air filter.

As Obie says. If it is fuel then it will probably be from the injector hoses, there are still quite a lot of M3W's with the original crimped on fuel hose clamps rather than the screw type that should be retro fitted by now. You usually get fuel spray onto the aero screen when driving as well, followed by crazed screens. If it is oil then it could be from wet sumping blowing out of the crankcase breather into the air filter of a crankshaft oil seal weep, oil coming out of the cambelt cover lower vent hole, neither of which are as serious as a fuel leak.

Thanks for the all the feedback. Thats has given me a few pointers to investigate. It certainly doesn't appear to be a weeping gasket in the crank. It could be coming from the air filter or the fuel systems above. When you say "starting the engine after wet sumping" what do you mean?

When the M3W has been standing for an extended time (think weeks) without the engine being run then there is a tendency on many engines for oil to drain from the oil tank, past the oil pump into the crankcase. On my car, around 2 Litres ends up in the wrong place. When the engine is subsequently started, the oil is pumped back up to the oil tank where it belongs. A small amount may also be 'burped' out of the breather pipe which connects the crankcase to the air intake. This can dribble down through the air filter and end up on the floor if it's not all absorbed by the air filter element.

This is a feature of many dry-sump motorcycle engines so we cannot point the finger at MMC this time!