OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines B&S 8hp white smoke - Rover Colt 8 Ride On

I've just put the engine back together after replacing the oil pan gasket and got it running only to find that there is now a bit of white smoke emanating from around the carburetor, muffler and air cleaner area after the engine has stopped running. It appears to be running cleanly - the smoke appears only when stopped. I don't recall this being the case before I changed the oil pan gasket. I changed the oil pan gasket because the engine was using a fair bit of oil and you could see that there was a fair bit of oil around the base of the engine on the chassis.

I have done a small amount of reading and it is suggested that the problem could be :-
- Overfilled oil - the manual says 1.1 litre of oil and I put in 1 litre
- Blown head gasket
- no doubt experienced mechanics would have other alternatives as well!

My question is:-

Should I replace the head gasket now or drain a bit of oil or let it burn off through runnning for a while to see if the problem continues - If the head gasket was blown will running it this way damage the engine?

Also whilst starting the engine I flooded it and there appeared to be an amount of fuel "blowing" out around where the carburetor joins the engine block - while I'm at it should I replace this gasket as well?

thanks

pcottam

Is it a flathead engine or overhead valve? If its a flathead engine I cannot see any reasin that a headgasket could cause your problem as no oil runs to it.

I wouldrun it for a while and recheck it for leaks after a really thourough wash and degrease, you should be able to see if there is a leak from weeping if you wash it and then run it for a while.

If the inlet manifold gasket is leaking I would replace it, from memory its a rather thick gasket, it would be worthwhile getting a genuine one.

Personally I keep the oil on the full line of any engine at all times, if its bang on the full marker you know if it loses any

Joe.

Thanks for taking the time to read and reply to my post Joe.

I have just run the mower for around 10-15 minutes mowing a small section of lawn and all is good - oil is showing just above the full mark and there was only a small amount of smoke when I had finished.

I'll put it to work again, probably on Sunday, and then look into the inlet manifold gasket whi0el the grass is growing again!!!

Peter

PS

I'm not sure if it is a flathead engine or an overhead valve.

It is a 193707-0367-0

Peter

A picture would tell a million words.


Are you sure the crank case breather hose from the valve chest is on the inlet manifold propperly???

Photo of Briggs & Stratton 193707-0367-01 engine

Your engine is a 19 cubic inch (311 cc) fourth design generation side valve model with vertical crankshaft, flo-jet carburetor, plain main bearings and a 12 Volt gear drive starter with alternator.

My first guess as to why it suddenly started emitting white smoke, is that you over-filled it with oil. You said that after running it for a while, the oil level is still above the full mark, and the white smoke has decreased. It is likely to continue to smoke until the oil level gets down to where it should be. Remember, you can only measure oil level with the engine on perfectly level ground, or the measurement means nothing.

The best and fastest way to sort out this problem is to get the engine level and see whether it has too much oil in it. If it has, drain just enough oil to get it precisely to the level mark. Overfilling is not really good for your engine, since it causes oil to enter the crankcase breather and be ejected into the engine at the carburetor. The engine will probably burn it without much trouble if the level is only slightly high, but meanwhile the crankcase is full of oil froth and this aerated oil is not ideal for lubricating the engine.

Thanks Grumpy - I appreciate your time.

I ran the mower for around 20 minutes this afternoon and all seemed to be ok.

However, I am still trying isolate the oil leak - I thought initially it was coming from the oil pan gasket and this was replaced - but after running the mower this afternoon I cleaned up the leaked oil and checked for leaks while the engine was running - I noticed a drip of oil coming off the bottom of a screw on the bottom of the governor control plate - I am not sure how to attack this without taking the governor control plate off.

thanks

pcottam

pcottam, I suggest you hold off a bit before taking action about the oil drip. Bear in mind my theory that you may have had the sump overfilled, resulting in oil passing through your breather into your engine's air intake. When that happens there is very often leakage of oil from the breather tube (the tube that carries the oil from the crankcase to the air intake) because the breather usually has a plastic right-angle fitting right at the carburetor, and the fitting is not designed to be oil-tight. If the oil level gets down to where it should be, oil will stop passing through the breather, and soon after that it should stop dripping, if my guess as to the cause is correct.

Still trying to stop the oil leak....

Today I took the Governor plate off to inspect behind it. I appears that the seal around the governor crank is leaking. Is this plausible - after degreasing and running the engine under load for about 10 minutes there was quite a puddle of oil sitting directly inder the lever assembly attached to the end of the crank.

I placed an o-ring between the retainer and the cotter pin in a feeble attempt to stop the oil leaking around the crank to no avail.



Can the oil leak around the governor crank? How difficult is it to replace the retainer?

Any help or assitance would be appreciated.

Thanks

pcottam

An oil leak around the governor control shaft would not cause smoky exhaust. It is also fairly unlikely that it could leak enough to form even a small puddle: the shaft only rotates a few degrees. I suggest you look directly above the puddle, but in other places. My favourite possible source would be the breather hose.

Thanks for taking the time to look at my post grumpy

The smokey exhaust has stopped however the leaking oil is now a real problem. I am having to top the oil up too much too often and the puddle of oil forming on the engine tray is too large to ignore.

I've just run the mower again to watch the oil leak form with the engine running, cutters engaged and the mower out of gear. i.e. under some load. I checked the oil before starting the engine and it was at the bottom end of the safe range - i.e. not overfilled.

The oil forms a slow but steady stream down the side of the outside of the engine base directly under the governor control shaft. So it must either be the oil pan gasket leaking or from around the governor control shaft. Can oil leak from around the cranshft control shaft? or should it check the tightness of the bolts securing the oil pan?

thanks

pcottam

It could certainly leak from the bottom crankshaft seal: where the crankshaft comes out through the crankcase cover, which you call the oil pan. That oil seal sometimes is damaged by something being picked up and getting wound around the crankshaft, above the pulley. However if it were leaking from the crankshaft seal you would see oil running over the pulley, and there would be oil on the drive belts.

It is relatively unlikely it would leak oil from around the outside of the crankcase cover: it would have to have been badly reinstalled during a repair operation.

Can you post pictures of the engine right where the oil seems to be coming from?

checked the breather

ive had engines just DUMP oil out them things......



kori

Pardon my ignorance - the breather looks like? and is located where?

PS - the photo above shows the engine after it was degreased and before running and showing the leak. The leak is around and below the governor crankshaft

I don't think your picture made it onto the internet, so perhaps you could try again. The breather is a tube that runs from the positive crankcase ventilation valve, near the valve chest, to a position at the bottom of the air cleaner, before the carburetor's venturi and throttle.

The govenor shaft should be above the oil level. The only oil it would be exposed too would be splash.
That O-ring held with the R clip like that does not look good and would never work. If you had enough room to put the o ring then a washer then the clip that might slow it down. Only thing you would need to be carefull with would be drag, too much and the govenor will not work propperly.


Breather valve is usually on the valve chest cover.