Leak

[Taped_Finger]

Evening,

I reached a milestone this weekend with my build and successfully started the engine.

When I was running the engine on tick over I noticed a pool of fluid under the car, first thought was that is was leakage from a loose coolant clip but on closer inspection, it was not.

I traced the area of the leak to be coming from the starter motor, my worst fear is that it's the rear crankshaft seal 

Has anyone had any experience of this kind of issue with a build or are you able to recommend any obvious checks I can look into?

I've emailed Caterham about it to see what they say.

[pgm]

Just wondered if the fluid is fairly clear? Could be clutch fluid if the the release bearing has a weep. Is the leak constant when the engine is running? The rear main would only fail if it had been incorrectly fitted.

Which area do you live in? If you are near either North Kent or West Sussex I would be able to pop in and have a look for you in the new year as I travel between those destinations. Alternatively I'm sure that there are other club members who would be willing to offer advice.

Kind regards PGM (Colin)

[Taped_Finger]

I did think it may be clutch fluid as I'm not 100% certain it's engine oil but I did check the clutch fluid level and didn't notice any drop in the level. 

The leak does seem to be pretty constant.

Thanks for the offer of popping around but I'm based in Scotland

[SM25T]

Put some on your finger and feel and smell it ... all have different feel and smell.

[David Brown]

Where in Scotland are you?

[Petethediesel]

As has been said, gearbox oil and engine oil are different in texture and smell. You will have both from the build kit. Put a drop of each on your left/right index finger  and rub with your thumb. The gearbox oil will feel more viscous and smell slightly acrid, like cats pee. Engine oil less viscous and very little smell, I had a minor weep from the input shaft seal on my Mazda 5 speed box and it certainly didn't drip as far forward as the starter. Showed on the joint face between gbox and bell housing and then on the bottom rib of the bell housing.

James Gibson is the warranty manager at Caterham but I know he's on holiday till the 2nd Jan. 

[ChrisC]

So looking at the photo I am guessing its a Sigma build, based on the starter motor bolt location. 

I would be shocked if it's a crankshaft seal problem, when they leak you normally see it first at the bottom on the bellhousing.   

Spilt clutch fluid from bleeding would be my first guess, but only you can tell from the consistency of the oil if its engine oil or dot 4.   Also if the slave cylinder was leaking again I would expect that to appear at the bottom of the bellhousing not on the starter motor. 

Therefore I suspect it's engine oil coming from above the starter, which leads me to think it might be from the breather or dipstick tube.  This can happen for a couple of reasons, but the obvious easy mistake to make is over filling the engine with oil.  This would lead to oil in the breather.   Over filling is easy to do given how clean everything is and the tendency for the oil to be pushed away from the dipstick when the level is checked quickly.  

Obviously check the black plastic cam cover, this was removed during the kit preparation by CC, but I would expect that to be more obvious.

I think beyond that your photography skill are going to be tested because you need a picture from above the starter motor.    

[ChrisC]

Also have you forgotten a breather hose.  I am just checking version 1.2 of the build manual for the steps (if it's in there) 

[ChrisC]

If it's a 310, then the 1.2 picture manual is not helpful.  It doesn't cover the fitting of the breather pipes and catch tank at all.   Page 85 of the old 2015c manual has some information on this, but this references the 140 (older engine).    

[Taped_Finger]

I have had another look today and it is engine oil.

The breather hoses on the engine where pre-installed and I've connected up the catch can and looking in that area i can't see any leakage around the hoses, but its all pretty tight in that area of the engine bay.

As the Sigma engines are pre-filled with oil, I just checked the level, and it's up to the max so I've not added any additional oil.

I did get a reply back from Caterham this morning, saying they would address it at the PBC, shame if they have to undo all the work I've done.

I may fire her up again to see if I can spot anything

I'm based just south of Edinburgh

[Taped_Finger]

btw ChrisC I'm really liking your blog.

[ChrisC]

Thank you, it takes a lot of effort, and comments like that make it all work worth while.   I will be making some progress this week and this weekend alone there is already 58 photos to be down sized and uploaded

There is no way that engine oil is coming from the starter, it has to be coming from something above it, unfortunately almost everything above the starter on a Sigma (except the 150) is covered with the plenum.   If you want to solve it yourself, I would be looking at finding a endoscope to find the problem.   The plastic breather block on the side of the Sigma engine block and the breather hose connected to it is almost directly about the starter, if you can't see oil from the cam cover it has to be the prime suspect.  That said I would also understand just leaving to CC for the PBC, it would be a large undertaking to remove, and would feel like a massive step backwards. 

 

 

[John Vine]

... it takes a lot of effort, and comments like that make it all work worth while.

I've just read your blog for the first time.  Excellent!  Well done.   And super-clear photos, too -- what camera do you use?

JV

[ChrisC]

They're all iPhone pictures, with the size dropped to 1/2 the original resolution.   Some will have had engine numbers or chassis numbers removed and only a hand full are picked for the blog. 

[Tom_Arundel]

I drilled a small hole in the bottom of the bell housing to show any leaks and I have seen leaky cam covers...this will have been removed and refitted when the cams were upgraded..the rubber seal could be nicked or misaligned

[ScottR400D]

Finding this thread on here from 2014 might help. 

OIL LEAK FROM UNDERNEATH CAM COVER (SIGMA)

I just searched on leaking sigma cam covers. It seems, like the Duratec, that’s it’s not uncommon. 

[Taped_Finger]

I started the engine again today.

I cleaned the starter motor prior and within starting the car and then getting out and having a look around, oil was starting to build up under the starter unit, I ran my hand up the side of the starter motor and no oil present and having a look as best I can with an inspection light I can't see or feel the oil coming from anywhere else.

I'm going to leave it for CC to sorted out.

Have a good Christmas everyone