Blue staining btween head and block

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Pete Bags
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Blue staining btween head and block

Postby Pete Bags » Sat Jul 04, 2020 2:37 pm

Hello all,

I'm hoping that the engine specialists here can help! My engine was rebuilt about four years ago, and it runs really well. It's a 1098, with a fast road cam, ported head, LCB manifold and HIF38 carb.

Over the past couple of years, I've noticed that some blue staining has appeared between the head and the block - looks like something is coming out. There is no noticeable reduction in the radiator water level, no mayonnaise in the oil filler cap. Engine sounds and goes very well.

My thoughts are that a) the blue staining is coolant leaking very slowly or b) gasket sealant oozing out c) head gasket issue d) something else

Picture attached.

Any thoughts - should I be worried?

Many thanks in advance,

Pete
leak.jpg
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King Kenny
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Re: Blue staining btween head and block

Postby King Kenny » Sat Jul 04, 2020 3:43 pm

It does look like blue coolant dripping down. You say your not loosing any, but over a long period a little weeping may not be noticed by looking in the radiator. Or it could be remnants of a gasket sealant. If the engine is running OK then I would not be worried.

philthehill
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Re: Blue staining btween head and block

Postby philthehill » Sat Jul 04, 2020 5:13 pm

Wipe off what is there and keep an eye on it.
It could be excessive head gasket sealant (not required ever) or a very slight weep of blue coolant.


les
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Re: Blue staining btween head and block

Postby les » Sat Jul 04, 2020 6:04 pm

You could also check the torque on the head nuts.


SteveClem
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Re: Blue staining btween head and block

Postby SteveClem » Sat Jul 04, 2020 7:00 pm

I wouldn’t be too worried, my Trav has done that for years..

Pete Bags
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Re: Blue staining btween head and block

Postby Pete Bags » Sat Jul 04, 2020 7:50 pm

Many thanks everyone for your suggestions - a quick question re checking the torque of the cylinder head nuts. In order to check that they are at the correct setting (just in case any were slightly over), should I slightly loosen all of the nuts, then torque up to the correct setting?

If I do loosen the nuts to do this, should I drain the engine block a little to lower the water level and avoid any possible contamination?

Thanks again,

Pete

les
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Re: Blue staining btween head and block

Postby les » Sat Jul 04, 2020 8:15 pm

I don’t think loosening the head nuts is advisable.


geoberni
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Re: Blue staining btween head and block

Postby geoberni » Sun Jul 05, 2020 9:07 am

Pete Bags wrote:
Sat Jul 04, 2020 7:50 pm
Many thanks everyone for your suggestions - a quick question re checking the torque of the cylinder head nuts. In order to check that they are at the correct setting (just in case any were slightly over), should I slightly loosen all of the nuts, then torque up to the correct setting?

If I do loosen the nuts to do this, should I drain the engine block a little to lower the water level and avoid any possible contamination?

Thanks again,

Pete
As an engineer, I would say never, NEVER, to loosen and re-tighten, because that is simply not 'checking' the setting. That is starting afresh. Especially important for anything that has a seal in-between.
Whether a cylinder head or something else, the correct procedure is to just get the right setting on a torque wrench and check each nut/bolt in turn as per the correct tightening sequence.

If you have a serious concern that something is 'slightly over' then the only option is to start afresh. But to be perfectly honest, I full y support the earlier comments. Just wipe it an monitor for a while, like a year or so. :wink:
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paul 300358
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Re: Blue staining btween head and block

Postby paul 300358 » Sun Jul 05, 2020 10:07 am

Is it a 940 head? If so, the waterways aren't exactly the same and you will get a slight weep over time. especially if its not used for a few days. In which case, check the water level and keep driving. If I park mine in the garage for a week, it will get a small blob of coolant on the flange next to the dipstick.
Also, mine is torqued to 50 ft.lb but I do have the later studs.

ampwhu
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Re: Blue staining btween head and block

Postby ampwhu » Sun Jul 05, 2020 10:13 am

my 1098 engine does the same. i did wipe it clear and it came back. I did a compression test and it was fine. I just clean it when i check the fluids now.

philthehill
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Re: Blue staining btween head and block

Postby philthehill » Sun Jul 05, 2020 10:32 am

To identify as to whether you have the later studs which allows a 50 lb ft torque - the later studs have a pointed top, an indent in the top or are stamped on top with a 'K'.
You certainly have the later flanged head nuts which must be used with the later 50 lb ft torque studs.


oliver90owner
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Re: Blue staining btween head and block

Postby oliver90owner » Sun Jul 05, 2020 12:05 pm

Different the geoberni. I was always taught to loosen each bolt by approx 90 degrees before torqueing down after the initial run. Each bolt in turn in the prescribed order - only one at a time, of course!

This was for re-tightening after the initial warm up after a rebuild. I would probably not recommend this after several years of running, as there may be unwanted deposits in any leakage trails and there could be some corrosion on fixing threads.

Can’t do any harm if the leakage would otherwise mean replacing the gasket anyway, but if only a tiny weep it is probably best left alone until the next time the head needs to be removed (and checked for flatness at the same time).

geoberni
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Re: Blue staining btween head and block

Postby geoberni » Sun Jul 05, 2020 1:58 pm

oliver90owner wrote:
Sun Jul 05, 2020 12:05 pm
Different the geoberni. I was always taught to loosen each bolt by approx 90 degrees before torqueing down after the initial run. Each bolt in turn in the prescribed order - only one at a time, of course!

This was for re-tightening after the initial warm up after a rebuild. I would probably not recommend this after several years of running, as there may be unwanted deposits in any leakage trails and there could be some corrosion on fixing threads.

Can’t do any harm if the leakage would otherwise mean replacing the gasket anyway, but if only a tiny weep it is probably best left alone until the next time the head needs to be removed (and checked for flatness at the same time).

I agree backing off 1/4 turn and retorque is a common practice after a comparative short period, especially with an engine rebuild, but that is part of the initial 'work', much as the tyre fitters will tell you to check your wheel nuts are tight after 100 miles or similar.

The OP said his engine was rebuilt 4 years ago, hence I gave my opinion based on that starting point.
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Pete Bags
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Re: Blue staining btween head and block

Postby Pete Bags » Mon Jul 06, 2020 10:58 am

Thank you all for your thoughts! Attached are a couple of photos - I have also looked to see which head I have, hopefully someone here can decipher the numbers I can see in the head casting to tell me the head actually fitted! The cylinder head studs under the rocker box cover are conical, but I did not see the letter K stamped - so should I be torquing up to 50lbs?

The engine has covered just over 7,000 miles since the rebuild. Interestingly, looking at the top of the casting (see photo), there is a uniform blue colour - seemingly the same colour blue that is weeping between block and head - just a coincidence?

The numbers/letters that I can see on the casting are as follows - some are difficult to read, but this is what I think they say:

MO 2310R (R might be a B) 6
23455 MOWOG 120202 B
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philthehill
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Re: Blue staining btween head and block

Postby philthehill » Mon Jul 06, 2020 12:41 pm

The studs look to be standard Minor ones so stick to the standard Minor head torque.

I suspect the head to be 12G202 which is a standard head for a 1098cc engine and not 120202 as quoted above. I think that the first '0' is in reality a 'G'.


Pete Bags
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Re: Blue staining btween head and block

Postby Pete Bags » Mon Jul 06, 2020 7:47 pm

Thanks Phil, you're right about my confusing the 'G' for a '0'.

I feel so very privileged to be part of this Moggy community where knowledge, advice and experience is given so freely. I enjoy working on my car and I am slowly pushing my personal boundaries to do more and more, but I also know my limits, so thank you all for making every day a school day for me.

All the best,

Pete

philthehill
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Re: Blue staining btween head and block

Postby philthehill » Mon Jul 06, 2020 7:52 pm

Pete
We all have to start somewhere.

I am lucky that I served my apprenticeship in a BMC garage when Morris Minors were still being sold as new cars.

Phil



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