My Robin Hood Heating Problems

[sanzomat]

Hard to say just from looking at the picture. Have you got the system up to temperature and had a look whilst the engine is running? If you see water/steam escaping then something definitely needs doing. It might be possible that the rusting is just historical.

If it is leaking but only slightly then I can't imagine that it is the cause of your overheating but could have been caused by it. It is possible that you'd get some localised boiling that would cause a pressure spike in the block but that would most likely quickly dissipate to the rad/expansion tank and vent off through the cap.

Overheating of the engine itself can cause HGF, especially with a cast iron block and aluminium head (looks like what you have). Not sure if those chemical treatments work - I'm always sceptical but as long as they don't clog anything up then it might be worth a go. If the HGF was caused by the engine overheating then it might just go again though.

One other thought. If your head gasket is blowing from cylinder to water you might be getting the symptoms of overheating without actually overheating. The pressure loss from the cylinder could go into the cooling system and vent off through the radiator cap giving the impression of boiling over. If your HG is leaking at the fire rings then I'd be surprised if anything out of bottle would fix it but I've been surprised before!

[Vindicator]

Hi Gary, looks like it's been leaking a for a little while. Just a thought (for what it's worth)..... the head around the exhuast manifold by the bolt appears to be stained, which is above the head gasket, so I wonder whether there is something leaking above that point. I can see a core plug clearly to the right of the bolt and there appear to be more above that point by the plugs. Is it possible a core plug is leaking?

Ian

[benchmark51]

Everything that isn't alloy or painted in that location is showing rust marking. I think this due to water splash and constant heating and cooling. It is probably an area that seldom gets cleaned or even wiped.
The way really would be to pressurise the system and check for leaks, although I have seen a lot worse without there actually being a leak found. I would give the area a good clean and see how it goes with periodic checks.

[Gary RH7]

Looks like I might have to investigate a bit more.

There is limited space for the camera so might have to take the starter motor out to look behind there. Looks though it is getting worse for wear now anyway judging by the nut and thread.

[damouk]

From my experience, any water leak no matter how small will cause a problem in some form or another, if you have a normal rad cap then in theory the cooling of the system will draw water from your expansion bottle back into the system keeping it full (as long as you have a good seal between the expansion bottle to the rad cap spout.

If there is a leak there it could be steam escaping and causing the surrounding area to rust, but it could also draw air in there too, depending on how your system works and is plumbed this might result in a build up of air at some high point and cause an air lock, this could at some point move to the pump and give you some cavitation, a change in revs might push the air back to where it was sitting or move through system and out to the header tank.

This is my theory of what was happening on the V-storm, I was loosing water from a small crack in my header tank (amongst other small hose clamp leaks). Initially I didn't see as a problem as I kept topping it up, but what was also happening over time was that the running temperature would vary more and more when I gave it the beans, I found that I could 'burp' out the air and the temperature swing would almost disappear again. A couple of my cooling system mods are to bleed off any air that could get trapped at high points.

I'm not saying you have the same problem but it might be worth thinking about, have you checked the car for air locks recently?

[Iancider]

I think Sanzomat has hit on the issue.  The external leak might be tiny and an indicator of something worse inside.  If the combustion pressure does get into the cooling system you can end up with what seems like an explosive boil-over especially when you cane it.  The pressure will fill the pressure vessel and empty the head but it will all potentially flow back again just before you open the bonnet (cunning).  When this happens you are also likely to have leakage between cylinders and a compression test will show that.

Also now I know you have an Ali head I strongly advise waterless coolant because electrolytic action between the mixed metal eats the aluminium.  No water means no corrosion.  Also the waterless coolant will run at the temperature of the thermostat unless you have insufficient cooling and that does not seem to be you issue.

Regards
Ian

[Gary RH7]

Thanks for all your input guys. Really appreciate it

Had a look last night around the core plug and it doesn't seem to be there. It is defiantly the head to block joint. Checked the torque setting on the wrench after taking a maths course and nipped the head down a little more and I did get a little turn on a few bolts.

Each time after I do a run or get the car up to temp I have recently been squeezing the top hose to see it I can hear air going into the header tank and there never seems to be any.

So, just ordered a compression tester as it seems to be the first area of attack.

[benchmark51]

The compression tester will test for cylinder compression and will identify a cylinder to waterway/oilway leak as well as cyl to cyl and valve leak. It won't identfy a waterway to atmosphere leak. A cooling system pressure tester will. They may be quite expensive so you could maybe borrow one or a radiator firm may test it for you.

Not seen it for years now, but Shell made a grease that changed colour when in contact with water.
The nearest I have found is Kolor Kut. It is a brown paste that turns red when in contact with water. A smear along the gasket joint will tell you of a leak.

http://www.ebay.co.uk/itm/131725191103?_trksid=p2060353.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT

[Iancider]

Or cheaper....

http://www.amazon.co.uk/Water-Finding-Detects-harmful-Heating/dp/B00NU6C036

[Gary RH7]

Compression Tests in psi

Ist run          135           117           140           150

2nd run         135          120            135           140

3rd run       no test        125         no test       no test

The tests were done with all four plugs out and engine cold
The 2nd port, 117, 120 and 125 I did three times as it was low to start of with but got better.

Could I ask the experts here what it means as it doesn't mean much to me except that it is not complete rubbish

Thanks

[benchmark51]

On the face of it I would say they were pretty bad. However, it depends on how you took the readings.
Engine hot or cold? Throttle wide open or closed? Engine cranked to max reading on each?

You could take a cold reading on each cylinder, thottle wide open till maximum reading on the gauge is reached.
Do the same but on a warm engine. You will probably find a difference.
I would expect readings to be upto 175 psi and within 10% of each other.

Your readings are a bit low and my first thought would be head off, not necessarily for a head gasket but a full decoke.

[Gary RH7]

On the face of it I would say they were pretty bad. However, it depends on how you took the readings.
Engine hot or cold? Throttle wide open or closed? Engine cranked to max reading on each?

You could take a cold reading on each cylinder, thottle wide open till maximum reading on the gauge is reached.
Do the same but on a warm engine. You will probably find a difference.
I would expect readings to be upto 175 psi and within 10% of each other.

Your readings are a bit low and my first thought would be head off, not necessarily for a head gasket but a full decoke.

OK I will try it warm with the throttle wide open which I didn't before... if I can find one of the family who can reach the pedal

One point to note is that the engine had a full re-con 3K miles ago albeit 20 years ago. So re-bore, new pistons, rings, valves guides and seats.Crank, cam etc etc.

[Vindicator]

Hi Gary, does the cylinder with the lower reading correspond to the possible leak you have in the head? A squirt of oil in the bore will help rule out worn/broken rings.

Ian

[Gary RH7]

Hi Gary, does the cylinder with the lower reading correspond to the possible leak you have in the head? A squirt of oil in the bore will help rule out worn/broken rings.

Ian

Thanks Ian, Look at the pics below taken from the top after clean up. The first pic is the two left readings and the second the two right readings. So the low reading is the top pic right plug. So its there a bouts.

[benchmark51]

One point to note is that the engine had a full re-con 3K miles ago albeit 20 years ago. So re-bore, new pistons, rings, valves guides and seats.Crank, cam etc etc.

I doubt it will need a decoke then

You could jam the throttle open at the carb linkage easily.
Be interesting to know the new readings and hopefully they will be ok. Taking the head off of dolly's can be a pain. See below

https://dollywiki.co.uk/wiki/Dolomite_1850_Cylinder_head_removal

[Gary RH7]

Yea Dave I have a link to that page and I have read it. If I have to do it I just hope the studs are still clean.
Just did it cold again with the carbs wide open. 140   140   140   150  ...now the battery is flat

[benchmark51]

Thats more like it . When you've charged up, do another test at normal warm. Should be higher readings, but if only a bit thats ok and if they are fairly close all the better.

[Gary RH7]

Did another run at normal running temp. Got 155   155   160   160.

Also put the water detect paste on the bad area. Nothing showing after blatting down to the garage and back doing 80 in third. Suppose I have to wait till summer now..if we have one

[benchmark51]

I think you are pretty well ok with the compressions, nicely close too. As you say the summer will be the test for it.

[sanzomat]

Why wait for summer -  might still be room on Moleman's track day in April?

Those compressions look fine and as they are all very close I don't think there is any sign of HGF there.

It might be that nipping up your head bolts has solved the leak (if indeed there ever was one)

So is it looking like the overheating is solved now then?

[Gary RH7]

Why wait for summer -  might still be room on Moleman's track day in April?

Those compressions look fine and as they are all very close I don't think there is any sign of HGF there.

It might be that nipping up your head bolts has solved the leak (if indeed there ever was one)

So is it looking like the overheating is solved now then?

Thanks for the feedback Dave and Dave.
Not sure about a track day yet Don't want to show myself up

Also not sure about the overheating but I have put a probe in the thermostat housing so I can see the temperature there. Its very close to the sender.

[Facial Hair Optional]

A track day would be a good test of the heating issue Gary and don't worry mate you would not show yourself up, most of us are not that quick! It's more about the fun to be had I think (despite all the ribbing that goes on about the VFC guys etc etc!), even going relatively slow it is a real adrenaline rush mate honest!

I'm starting to get worried myself that I will be too unwell to make it now  Somehow I have to get myself sorted before the Combe day next month or I'll be watching from the sidelines. Bummer that'll be - I will never hear the end of it from Moleman!!

[damouk]

A track day would be a good test of the heating issue Gary and don't worry mate you would not show yourself up, most of us are not that quick! It's more about the fun to be had I think (despite all the ribbing that goes on about the VFC guys etc etc!), even going relatively slow it is a real adrenaline rush mate honest!

I'm starting to get worried myself that I will be too unwell to make it now  Somehow I have to get myself sorted before the Combe day next month or I'll be watching from the sidelines. Bummer that'll be - I will never hear the end of it from Moleman!!

Don't you worry about that Steven if your not well enough I'll take the asbo round for you

[Facial Hair Optional]

There's a right load of jokers on tonight!! Haven't you got homes to go to!!!

I haven't been called Steven since the last time my mum told me off. Which actually was today funny enough! 

[Moleman]

Hope you will be ok for the track day mate.

Gary I think Steve is right, the track day is a great way to test it. 

[damouk]

I haven't been called Steven since the last time my mum told me off. Which actually was today funny enough! 

That was actually my phone trying to be clever with its autocorrect, obviously it's got a better sense of humor than I have!

[damouk]

I was always sceptical about my cooling fixes, but was pleasantly reasured when I took it to combe.