Head gasket question

[998automan]

Hi, after a fairly long run today I noticed that a small amount of oil is leaking from around the head gasket. (It`s not coming the rocker gasket as this is bone dry!) I was thinking about re-torquing the head and if that doesn`t help was wondering what my options are other than changing gasket? Coolant appears to be clear at the moment so doesn`t look like any oil is getting into cooling jacket?

[robertm]

I had a similar issue but mine was a little anti-freeze showing up just above the water pump/below thermostat.

This was last November and a neighbor of mine that has owned several Midgets and Sprites suggested I re-torque the head bolts and it worked for me.

I used the sequence in the Haynes manual and started from Stage 1-34Nm and then Stage 2-68Nm.

At that point none of the fasteners moved so I gave studs 8,7 and 4 a little movement tighter, maybe an 8th of a turn or less.
(The sequence I used is from the blue 1969-2001 Haynes and for pre Oct 1996 model)

The lube oil and anti-freeze both show no signs of cross contamination before and after re-torquing.

I hope re-turquing works for your oil weeping situation 998automan.

[998automan]

Thanks, checked this today and everything torqued down as it should be so not sure what to do now!?

[Stu]

Might be worth doing a compression test on the cylinders. If you get a low reading on the cylinder closest to the leak it might suggest a leaking gasket.

I think I'd try that next if it were me

[998automan]

Thanks Stu, do you have any experience of the gasket sealants that go in coolant (such as Mafco) they are expensive but claim good results? Not too keen on doing yet another head gasket as this would be fourth attempt!  

[minigman]

Sorry to butt in but I ran my engine for about a year on a sealant added to the coolant. I was advised not to do it but the engine was very tired so I thought why not. Solved my head gasket issue at the time before the engine was replaced.

[998automan]

No problem! That`s interesting to hear, don`t suppose you can remember the name of the product? Also interested as to why you were advised against doing it?  

[minigman]

It was K Seal. Was told it would blog the rad up and heater matrix. I'm not sure it would have lasted for ever but the rad and matrix worked fine. Hope that helps.

[Stu]

How frequently are you having to re-new the head gasket. 4 times in what timeframe?

[998automan]

Hi Stu, initially went about 2 years ago after I flushed out loads of stuff from the cooling system before changing the rad (about 10 rad welds worth I reckon!) Failed almost immediately after that. Replaced head with Mini Spares `re-con unit` (use the term loosely) was ok for a short time but engine developed knock on rolling road so took it off the road for a rebuild. Head & block was checked for flatness during rebuild and all was ok for a while until new double valve springs starting pulling valve stem seals off! Took head off to fix this and gasket didn`t seal properly, took head off again and replaced with better quality copper gasket and torqued down as per manual. Coolant looks ok at the moment but a small `weep` of oil can be seen around front of gasket (rear is dry) after a short run.    

[Stu]

Ah ok. I assume you've checked the oil pressure relief valve is ok an not sticking?

[998automan]

Er, no! Any tips on how to do this?

[Stu]

I think it's unlikely to be the cause but worth checking anyway.

Its the capped nut in the photo below underneath the oil pressure sensor. unscrew it and withdraw the spring and bullet. Give it a clean and ensure the spring is operating ok. Its a simple bypass mechanism to allow oil flow back to the sump (I think) in the event of too higher oil pressure. Kind of a safety release valve.

[998automan]

Thanks Stu, that`s awesome! Will let you know how I get on.