- My model of MX-5 is: NA … 1996 1.8 … UK spec so no power steering or aircon
- I’m based on: The isle of Wight
- I’m looking for technical help or recommendations on: Curing the oil leak from the main crank seal at the front… the one that presses into the oil pump, just behind the pulley wheel.
Mine has some damage on it… some owners are hap fisted and I guess it takes effort to put marks onto a crank shaft… and they have managed it. I don’t know how far the rough bits go and I’m trying to avoid taking the engine right out…
It’s been suggesting that I could fit a speedi-sleeve on there. I’m tempted to try but… but what about the shoulder of the sleeve… will it get in the way of anything as it’s probably not possible to get into that space and remove it without removing the oil pump (and to do that then engine has to come out…) …and of course what size sleeve would I need to purchase… these things almost need specifying to the micron and I’m not sure if I can get my vernier calipers in there well enough to get a good reading without… you guessed it… taking the oil pump off which means engine out!!!
Anyone got any advice here? I’m fed up of leaving a dark mark (that’s not as cool as Voldemorts) everywhere I go.
Also… so much mess but no apparent movement on the dipstick… how is that possible!!!
Have you considered a double lipped seal, if one exists in your size of course.
Also, if you’ve had the pulley off, you may be able to grab the numbers from the front of the seal.
These numbers usually indicate the size.
I don’t recall the exact way they work, but something along the lines of outer dia, inner dia and thickness.
Eg 402510 would be 40x25x10.
A double lipped seal is a new idea for me. Wouldn’t know where to look for one either. A specialist oil seal company? Certainaly worth considering if it will save having to remove the engine.
I’ll try and see if there are any markings on the exiting seal for sizing.
Thanks for ideas @Keat63 … appreciate it
Its very easy to fold the lip inside out when fitting the front seal which is hard to see but will cause a leak. Its not easy even with engine on the workbench.
A common area for oil leakage around the front of the engine is the sump seal. There is a short rubber gasket that runs between the oil pump and the curved part of the sump which can leak. Are you confident that the leak is coming from the front main oil seal and not this gasket?
Yes - very sure… the leak stops for a couple of hundred miles when this seal is changed… then it slowly starts again. I believe there is damage to the shaft where the seal sits which is causing the failure.
What would I need to look for to tell if this is the case? I can get an endescope down there and see things in pretty good detail… and advise on how to fit the seal without it happening?
Also something else you could try.
Taking the measurement numbers, and see if a thinner seal exists. Then try fitting 2 seals.