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Don't get all excited, the first word in the title is an adjective and not a verb.
Engine is a 99 1.8L with about 100k miles. Had the head off a month ago to put in ARP head studs. The car has always had a hidden slow oil leak and I was hoping it would go away after the teardown since I replaced damn near everything including the camshaft seals. Decided to put dye in the oil last weak and determined it was the cam shaft seals leaking down the metal plate under them. So last night I tore down the bare essentials to get to the camshaft seals. Pulled the caps off holding them in and cleaned all the surfaces. I inspected everything, and there were no big gouges or anything I could see of feel that would cause a leak.
Decided to use Hylomar Blue on the outer part of the seals and the seal mating surface on the block and caps in the hopes that it would seal them in better. Oiled the inner part of the cam seals and then pressed them in using the Flyin Miata tool. Let the valve cover rtv cure overnight (in the six vertical spots). Drove the car today for about 15 min and as soon as I pulled in I could see oil dripping off the bottom of the front plate.
I've read everything there is about putting these in and it seems very straightforward. There does seem to be an oddly high number of threads across the internet about these seals leaking, but no definitive fixes.
Just a note, the first time the cam seals were installed by me I did oil the outside and inside like it says to do most places. I only tried the Hylomar blue the second time and it didn't work either.
Anyone have any thoughts as to what the issue might be?
After dozens of timing belt/water pump jobs (including cam seals), I’ve found some Miata engines just like to leak at the cam or crank seals. Just needs lots of cleaning and proper rtv’ing at the corners. As long as you’ve done all that correctly, there’s only so much you can do.
After dozens of timing belt/water pump jobs (including cam seals), I’ve found some Miata engines just like to leak at the cam or crank seals. Just needs lots of cleaning and proper rtv’ing at the corners. As long as you’ve done all that correctly, there’s only so much you can do.
Thanks Curly!
What is your strategy for cleaning? Would polishing or scuffing them up with scotch brite help at all?
Do you think a good synthetic grease might help on the inside of the cam seal instead of oil?
Just realized there are eight different manufacturers of these camshaft seals just on Amazon and Rock Auto. Said screw it and ordered one of each. Just for curiosity sake I want to know if there are differences between them. If one of them works, it will be well worth the $40 for me.
My exhaust cam had a very small ridge where the inner seal sat. I asked my friend about camshaft repair sleeves, but he suggested the easy solution - don't bottom out the seal, bringing the inner seal forward a smidge. Didn't leak (much) after that.
I've no exp with this hymolar stuff but I'd try regular rtv/gasket maker stuff that does set. that's what I use to thinly coat the outside seals on prev builds and none leaked
I've no exp with this hymolar stuff but I'd try regular rtv/gasket maker stuff that does set. that's what I use to thinly coat the outside seals on prev builds and none leaked
My exhaust cam had a very small ridge where the inner seal sat. I asked my friend about camshaft repair sleeves, but he suggested the easy solution - don't bottom out the seal, bringing the inner seal forward a smidge. Didn't leak (much) after that.
1/16th is reasonable. I just so happen to have that head sitting on a shelf (excuse the crud, it needs a machine shop visit before it goes back into a car).
And for comparison - here is how bad it was before I moved the seal up
What brand seals are you using? OEM from Mazda are the only ones I will use now. I have had far to many parts store seals leak to ever keep using them. Cam, crank, main, oil pan, and rear are always 100% OEM in my motors.
What brand seals are you using? OEM from Mazda are the only ones I will use now. I have had far to many parts store seals leak to ever keep using them. Cam, crank, main, oil pan, and rear are always 100% OEM in my motors.
I'm using Apex brand now from Rock Auto. Where are you getting them online to be sure they are 100% OEM?
What brand seals are you using? OEM from Mazda are the only ones I will use now. I have had far to many parts store seals leak to ever keep using them. Cam, crank, main, oil pan, and rear are always 100% OEM in my motors.
+1000. Last time I had a leak like yours (it leaks at the dynamic junction between cam and seal), it was both sides based upon basic head-rebuild kit seals. Pulled those out, put in OEM and it's been fine ever since.
Originally Posted by LukeG
I'm using Apex brand now from Rock Auto. Where are you getting them online to be sure they are 100% OEM?
I am going to echo the some engines just leak. I have replaced the cam seals on my 1.6 3 times now. Twice with after market and this last one eith OEM. They last a few thousand miles and then start leaking. I even tried not bottoming them out this time and same thing. So now I let them leak.
I've faced this as well, the OE and aftermarket replacement seals sometimes move the actual sealing position so as to avoid a groove in the cam. In the end, I ended up sleeving the end of my cams and using OE seals which solved my problem.