I changed my valve cover gasket today, however when I went to torque down the bolts, I realised that my torque wrench is the more heavy duty one that starts at 120in/lb, and I need one that goes down to 43-78 in/lb. I’ve tightened them down to wrist tight while holding the head of a ratchet wrench, rather than torqueing using the end of the ratchet’s bar. Machine Mart is only a minute or two down the road, so the question is… Is it safe to drive there to get the lower torque wrench with the bolts as tight as they are? I’m guessing 43 in/lb is not that tight anyway, and it feels tight enough to have sealed the gasket…
Any advice from someone who knows would be much appreciated!
Hi Mike, it shouldn`t be a problem but I would advise just going around the bolts again in the morning in a spiral pattern from the centre bolt and working outwards and just gently tweak them all to about the same force as is normally required to undo a lid on a new jam-jar … ish!
I tighten these down several times a month and have a pretty good feel for what torque a given size of fastener bolt threaded into aluminium alloy ought to be from my early days as an aircraft engineer and am yet to strip a thread or snap a bolt into an alloy component on an MX5 but if you are not all that used to doing up bolts into alloy its definately best to use the correct torque wrench.
Did you put a little blob of hi-temp silicone sealant on the 6 points of sharp angle change where the gasket loops up and over the cam seal housings and cam angle sensor at the back end?
I always pop a small blob of silicone sealant down the cam cover-bolt holes (two outer rows L&R) as quite often I have found oil can leak down the threads and drip onto the exhaust manifold heat-shield, resulting in a stinky motor, not something found in the text books but good engineering practice.
Cheers for the advice! Yep, I smeared a couple of mm of high temp silicone sealant in the 6 corners. I changed the gasket as oil was leaking from the rear cam arch, so I guessed sealant was probably the issue. Also looks like the gasket was a cheap copy and not the Mazda part, based on what I’ve read on this forum and comparing the old vs. new side by side. I also couldn’t see much sign of sealant having been used last time the cover was fitted. I’ll check the bolts again this morning and nip out to get the torque wrench.
Something else I was wondering… How frequently do people normally replace the valve cover gaskets? I’m guessing every time the cover comes off is probably too much…
Lastly, now I think I’ve sorted the leak, I’d like to clean up the oil slick down the back of the engine. Is de-greaser, a tothbrush and a low pressure steam cleaner a suitable tactic?
It’s a cheap Karcher from Argos, around £130. It’s only 3bar max pressure, which is much lower than the professional garage units which I believe go up to around 30bar. It’s less of a jet-wash steam cleaner and more of a hamster blowing steam through a straw… It’s worked wonders around the car though, cleans upholstery, leather, interior plastic, bits of engine etc. I’m just wary of pointing too much steam at the electronics in the engine bay, and the coil pack is right next to the oil slick!
Hi Mike, I use brake and parts cleaner for pretty much every heavy duty cleaning job around the car (and house!!!) and sometimes even the laundry as it is great for removing oily marks on clothing, shoes etc.
If you are planning on regularly tackling dirty jobs on your car it is worth considering getting a Wurth spray bottle for the wonderful stuff but buy the liquid as cheap as you can in a 5L can from whatever motor factor you have blagged a 20% discount from
Do follow the health and safety instructions and remember the vapour is heavier than air and as such should not be used in large quantities over a pit or without the work area being well ventilated, never spray on a hot or running engine, as it is highly flammable (a BMW dealership in Swansea burned down recently due to a large quantity of vapour at floor level being ignited by a bench grinder being operated with the sparks setting it all off) allegedly.
You do not need a pressure washer for this,hose pipe,brush’s,plastic bin back and TFR will bring it up to show room, i did have a thread somewhere,but cannot find it?don’t waste your money for this.
