Jump to content
Click here if you are having website access problems ×

Oil leak !


kiloromeo

Recommended Posts

Hello everyone, hope you don't mind me asking the experienced owners on here for an opinion before contacting Caterham...

Car is a just over a year old, 270S (Sigma/mazda gearbox), less than 3000 miles. Kit built, engine arrived prefilled with oil. When mating the gearbox/bellhousing to the engine, I don't recall a gasket and in fact there is a small gap at one point (like a O mating to a D)

Last year I noticed that the garage floor looked like it had a wet patch, and put some cardboard down to try and find if it was oil or water. It seemed to be oily, so checked oil was ok (it was above the min, but topped up a little anyway.). No more signs of a leak.

After the first proper blat out this year I put some cardboard down, and hey ho the following day another wet patch appeared and a dribble of brown oil. Which oil, engine, gearbox, clutch fluid? See pic...

Looks to me like it it comes from the bellhousing to engine joint during? and after driving, but cooled down and sitting in the garage it doesn't leak?  *scratchchin*

IMG_20200521_183349.thumb.jpg.da8bb55a7bd438f2ec2479c41b3dea8a.jpg

Link to comment
Share on other sites

Gear oil usually has a distinctive smell and is sometimes dyed red too - did you build the car if so what did you use..?

Looks very clean for engine oil unless its a new build

Brake fluid has a slightly dry feeling when rubbed between thumb and finger compared with oil and again a different smell - pop your nose in the fluid reservoir for comparison.

Unless theres an sign of oil running around block to sump joins then it is looking like pulling the engine as all 3 sources are in the bellhousing...

 

Link to comment
Share on other sites

Just to say I've got a 2009 Sigma based 7 and I have had this, I think its to do with the slightly over filling of the engine oil. It seems to be quite sensitive. Particularly if if gets hot after a blat.

I had exactly the same panic

Mrp

Link to comment
Share on other sites

I had similar so I drilled a small hole at the lowest point of the bell housing to prove where it was coming from...it was and has always been dry inside....I have blown the dipstick out on a few occasions..that`s quite messy! Your oil does look clean so could be gearbox....I know you have the Mazda box but the Ford type 9 used to leak from the selector rails and dribble down in that area. Has the oil slick spread on the underside of the floors or on to the A frame/Dedion? Mark the clutch fluid level on the reservoir and monitor it.                I worry more when mine stops dripping!!

Link to comment
Share on other sites

Good chance it’s the rear main seal. Symptoms fit and it’s not at all uncommon with the sigma especially in 7s and at low mileage. Quite a bit of stuff on YT about this range of engines which all have a similar seal. Caterham carry stock of seal as do Ford dealers which tells you something  

It can be done yourself but needs much more effort than you’d think. Engine out, sump off, great care fitting new seal and housing, making sure it’s central on crank, torqued up correctly. Special sealant, carefully applied to sump which needs to be fitted in a certain way. 

Much more complex than many RMS replacements. 

And if course the clutch needs removing and refitting with retorque of flywheel (112Nm IIRC).

If none of that makes sense I would suggest you get it done by someone who knows the job and who will stand behind the work.

I believe CC charge about £900 or so to do the job. 

Link to comment
Share on other sites

Thanks for the replies. Car is 1 yr old kit built, approx 2,800 miles.

The gearbox and engine were prefilled with the supplied kit, so not sure whats in the gearbox.

Will check brake and clutch fluid levels, then fire an email off to see whats what.

Link to comment
Share on other sites

Non on a Sigma but on my k-series I had a very similar looking leak with almost identical symptoms. Took ages to finally find it but as Scott says it was the RMS, so that would get my vote as the culprit. It wasn't sealed in quite properly so leaked slightly, either when the oil got hot (so thinner) or when left standing and the oil behind the seal gradually leaked out over time. 

Obviously a major job to change unfortunately. 

Graham

Link to comment
Share on other sites

Could be. I shall stand to be corrected. But it looks like engine oil, and surely if you'd lost that much fluid you'd know about it? Just thinking that by the time its left the slave cylinder, run down though the bell housing, spread over the outside and dripped on to the floor like that? Twice? 

I hope I'm wrong actually, its not a fun job. 

 

Link to comment
Share on other sites

Well I've checked the brake and clutch fluid levels and they seem ok. Clutch fluid looks dirty though *scratchchin*

I can't smell very well right now due to hay fever, but I dripped a little engine oil from the dipstick next to the leaking oil patches for comparison, the 2 light coloured spots are the leaking oil, the dark brownish drop is off the dipstick....

IMG_20200526_151812_1.thumb.jpg.8103dbff0907ec4fd2659d656969d50f.jpg

Link to comment
Share on other sites

So the real question is, what oil is it? There is a lot for it to be clutch fluid. You should be able to tell if it's clutch fluid by the feel. The engine oil from the dip stick looks darker than the leak, which makes me think it's not engine oil. That leaves gearbox oil, but you should be able to smell it. If you can't smell it, maybe you can get someone else to.

If it was my car, I would clean all the leaking oil from the bell-housing; then I would run the engine. Let it run until the cooling fan kicks in. If the leak reappears with the engine idling, then I would suspect engine oil leak, either sump seal to engine, or crank main oil seal.  

If the leak does not reappear, then take it for a short drive. If it appears after that, then I would suspect gearbox. Look at the fill plug and reverse switch on the side of the gearbox (difficult, I know)

Link to comment
Share on other sites

Kiloromeo - please read the posts about the feel of the oil. Rub brake fluid between your fingers then do the same for engine oil to get that comparison and compare it to the leaked oil. Gearbox oil is VERY distinctive in its smell. If you have someone at home who can smell it for you that would help, alternatively you can drive the car to someone's house as part of an eye test (up to 60 miles round trip). The photo doesn't help much in understanding what oil is leaking. As already said too, get it degreased and let it run up to temperature and then get under the car again as that will help you.
Link to comment
Share on other sites

Finger test is a good idea, brake fluid soon stops feeling oily. 

Wash your hands soon afterwards. 

Checking rear of engine for oil coming from cam cover is a good idea too. 

Not sure the colour of the fluid says much, we did a RMS on a 310 last year and the oil looked clean as it leaked. Just like this.  More miles than this case too. 

I think the Mazda box is less likely to leak than the old boxes and it would be a fairly significant leak to get all the way down the bell and then out. IMO. 

If the rear of the engine’s clean I think the engine’s definitely going to have to come out to check. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...