Burning oil smell .

fj12_rider · December 14, 2012, 08:20:26 AM

A little help if you please .

My 3CV has a burning oil smell . It doesnt seem to be burning it but when i sit at the lights I can definately detect a burning oil smell . Could it just be that the oil needs changing or is there some other reason ? Any advice would be great .

Steve_in_Florida · December 14, 2012, 09:19:34 AM

It's possibly oil leaking from the valve cover gasket or seals onto the head, and burning off.

It's high enough that it wouldn't drip on the ground, and hidden enough that you wouldn't notice it on a cursory inspection.

Look for a thick, molasses-type substance on the cylinder head or piston barrel fins.

Also, make certain that your crankcase breather tube is connected to the bottom of the air box.

Steve

fj12_rider · December 14, 2012, 09:26:53 AM

Cheers Steve . I`ll get out there when we get a break in the rain and have a look . I`m pretty sure it`s nothing serious because it`s running sweet as a nut and I mean very very nicely . It`s just one of those niggling things I cant seem to locate . I`ll have a good look tomorrow . I`ve just bought some new oil to put in as i`m not sure when it was changed last . When I put that in I`ll pull it about and take a good look in the places you suggest.

Dave !

airheadPete · December 16, 2012, 10:44:34 PM

You do not need to change your oil! (You've got a schedule for that, yes?). You probably have a seep somewhere hot. (The head.) You may want to pull the tank and set it 180* out onto the tooltray/fender and let it idle in the garage. Then you'll probably get it to smoke from wherever the oil is cooking off. Look for glazed, shiny black deposits.

fj12_rider · December 17, 2012, 01:06:49 AM

Thanks mate i`m going to get into it today and I`ll do what you suggested . cheers !!

Goetz · December 22, 2012, 10:31:26 PM

I bet its the valve cover gasket or vc bolt seals. Not a big deal

mr blackstock · December 23, 2012, 04:19:23 PM

The crankcase breather that goes from your crankcase to the air filter intake underneath the carb bank may have come off, meaning all the bypass gases are going straight into the air. A lot of people fit a breather filter to the crankcase breather hose and plug the breather intake hole on the air filter box, because the hose hardens over time and is impossible to re-connect.

Maybe this could be the problem?

cheers, Gareth

fj12_rider · December 24, 2012, 06:24:34 PM

Cheers for all your help guys . I`ve given it a good clean up and will have a better idea what it is later . I`ve been banned from tinkering until thursday ..lol .

fj11.5 · December 24, 2012, 07:11:34 PM

THURSDAY , that's dayyyys away , surly you can sneak half hours tinkering in before then

fj12_rider · December 25, 2012, 04:09:36 AM

...I`m going to give it a good try . If you dont hear from me for a few days i`m in hospital having my testicles reattached hehe

fj11.5 · December 25, 2012, 04:49:39 AM

Ouch, depending on what your going to attempt to fix or upgrade the pain may be worth the effort

fj johnnie · January 31, 2013, 06:03:00 PM

A Yamaha mechanic friend refers to the FJ as "the sprinkler". Valve cover gaskets tend to dry out and crack. Be careful what you buy, I purchased one on fleabay and it would not fit. The Yamaha gasket was much more money but took 10 minutes to install. I fiddled with the lousy aftermarket piece of crap for hours trying to make it work. Sometimes saving money costs twice as much.

I have had several FJ's and usually the first sign is the smell. I would recommend replacing the bolt grommets at the same time.

gonzajr · April 21, 2013, 11:47:42 PM

Quote from: fj12_rider on December 14, 2012, 08:20:26 AM
A little help if you please .

My 3CV has a burning oil smell . It doesnt seem to be burning it but when i sit at the lights I can definately detect a burning oil smell . Could it just be that the oil needs changing or is there some other reason ? Any advice would be great .

Hello if your fuel tank is low on fuel; this is a good time to remove it and check valve cover rubber grommets around the bolts on the cover.
My 89 fj1200 had the same problem, But at the time I needed to adjust the carburetor's so I just cleaned off the residue at a car wash.
I live a close distance from a car wash I trailer it there; I also cleaned above the header pipe where the block meets the valve cover.
If possible blow dry around the plug wires and all the wire connection that my have gotten wet.

gonzajr I hope this helps

Steve_L · March 05, 2024, 04:26:35 AM

Quote from: fj12_rider on December 24, 2012, 06:24:34 PMCheers for all your help guys . I`ve given it a good clean up and will have a better idea what it is later . I`ve been banned from tinkering until thursday ..lol .

G'day mate
I appreciate that this is the thread revival to beat ALL thread revivals https://fjowners.com/Smileys/default/facepalm.gif
11 years on now, do you recall what the issue was?

Pat Conlon · March 05, 2024, 04:26:23 PM

2 sources of the smell,
1) Leaking oil from valve cover gasket, bolt grommets or cam chain tensioner.
2) Our FJ air cooled engines run loose piston to cylinder wall tolerances and thus gets a lot of blow by. Just the nature of the beast. Nothing can be done about it, so you can smell this oil vapor blow by from crank case vent tube, if it becomes disconnected from air box or.... if the air box is removed and aftermarket air filters are used, then the oil vapor is coming from the small filter on the crank case vent tube. If this is the case, position the vent tube and filter under the carb filter so the carb draws in the vapors.

Cheers. Pat

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Burning oil smell .