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Old 22nd May 2020, 16:20   #71
Fred Byrne
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What a saga. Hope it all ends excellently!!

Fred
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Old 22nd May 2020, 17:26   #72
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... why won't the tools fit?
We'll need to explore a few possibilities.

Do you have the INA instructions to set-up the timing belt tensioner pulley (not included in Haynes or RAVE)?

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Old 22nd May 2020, 18:40   #73
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No I don't but I doubt that is a problem because I didn't interfere with it and it was working perfectly ok before. I was thinking Haynes and Rave do not mention anything about putting the timing tools back on after the belt has been put back on Haynes only mentions that after putting on the new belt you should turn the engine over twice to see that the marks line up which I did and the marks on both sprockets line up ok. As I said when I put the timing tools back on one is ok but the other is very slightly out, should i ignore this and just proceed, what are your thoughts.

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Old 23rd May 2020, 15:40   #74
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I think this is due to the tensioner taking over the responsibility for keeping the belt taut. I bet it is the rear bank that is slightly out. What you could try is bring the crank to the safe position and put the timing tools on the bank that is correct. Then slacken the bolt on the other bank's camwheel and see if you can reset that camshaft with the other timing tool. Then re-tighten the bolt. Do you have to replace the bolt with a new one? I think probably yes.The theory is that if it is due to the timing belt settling in, the camwheel will rotate slightly to accomodate the very small change in belt tension. If it won't reset it will probably be due to the fact that the camwheel is as far anti-clockwise that the keyway will allow it to move. I had this when I put my new timing belt on and decided to ignore it. However, there is no doubt that the timing on one bank is correct and the other is out by about a degree or two. That's my theory but someone more experienced and more knowledgable will have a different view. Coming back to your coolant leak.
I have been chasing a similar leak for about a week.
I found two leaks one at the elbow on the off-side top of the radiator. This was only present when I ran the engine and the pressure built up. It was cured with a new 3mm thick 'O' ring. I was then left with a leak of 100ml per 24 hours. It is generally accepted that one drop is one tenth of a ml. So I had a leak of 40 drops per hour or one drop every 2 minutes. I realised that this is tiny and the drop may well dry up before it falls or seep along some joint and evaporate. I examined every hose joint that could have been disturbed when I was working on the engine. I found that one of the clips on the oil cooler was damp underneath the clip. This was the culprit. It was undetectable until I slackened the clip just enough to see underneath the clip itself. So it appears the coolant evaporated before it became visible . That has been my recent experience and it was so frustrating and time consuming because you had to wait so long between each check on the coolant level. So I do hope that when you get around to the coolant problem again that you will be able to solve it with some similar simple remedt.

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Old 23rd May 2020, 19:14   #75
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Yes Fred your coolant leak looks a relatively easy fix compared to what i have had to contend with. I have had the heads off and it is a huge amount of work. I did it about seven years ago when the cam belt snapped because of a seised belt tensioner and I must admit that at the time I said it would be unlikely for me to ever do it again but I must be a sucker for punishment. In fact it all went reasonably well until the camshaft broke and it has gone downhill ever since. I have noted what you say but I think in the end it will be better to take the primary belt off and start again and also do the secondary belts again as well, after all I have all the bits taken off so that it shouldn't take too long and I must try and get it absolutely right. I didn't have such a problem last time so I can only think having the heads skimmed has changed something. Also, last time I had someone to lend a hand and now I am seven years older and I did most of the work up till now on my own with only a little help from my wife. I have now asked a friend to give me a hand hopefully next week so that should help, I hope!


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Old 23rd May 2020, 22:50   #76
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If you have a friend helping who is patient then I would do the rear belts with the heads off. That is if you have the heads off already. It is the valve springs acting on the cams that make that approach difficult. You need three arms fully available to do it!

Good luck.

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Old 6th June 2020, 11:10   #77
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This is an update to the coolant leak problem. I decided that as a last resort that I would remove the heads. It is a massive job and made even more difficult without assistance which was not readily available in these times. If I had to do it again, which I hope not, I would't do it without assistance being available. For instance, such assistance is useful because it it much easier to remove the heads without removing the exhaust manifolds and then replacing the heads with the exhaust manifolds fitted because access to the manifolds is so limited.

Upon removal of the cam covers I discovered a thick layer of emulsified oil i.e. mayonnaise! There had obviously been a head gasket leak for some considerable time, as I thought. Just goes to show that you cannot trust those chemical testers. Upon examination of the head gaskets there was no evidence of an obvious defect but when I did this job seven years ago I did not use genuine gaskets on the rebuild so there is a lesson there.

I therefore had both heads pressure tested for leaks, no cracks found, and both heads lightly skimmed. The engine was carefully rebuilt with genuine MG Rover gaskets and I found the head gaskets did not have the word "top" on them which I had not come across before, however worked out which was the correct way round.

It fought me all the way but eventually got it all fitted back together. It started immediately but rattled presumably because there was a lack of oil in the tappets but it is now running nicely. Had to top the coolant up once after it had cooled down and have now covered about 130miles with no leak!

I hope that this is now the end of this long running saga and perhaps Kaiser who said I must be mad to take the heads off will reconsider what he said!

Martin
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Old 6th June 2020, 12:09   #78
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There had obviously been a head gasket leak for some considerable time ... Just goes to show that you cannot trust those chemical testers ... there was no evidence of an obvious defect but ... I did not use genuine gaskets ... so there is a lesson there.
Thanks for this interesting and valuable feedback Martin. I have never been entirely convinced by the chemical testers either. From what you've discovered taking off the cam covers and having a look is the most reliable option. Thanks also for alerting us to the perils of using non-genuine gaskets in this critical application. It's good to know that no cracks were found.

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It started immediately but rattled presumably because there was a lack of oil in the tappets ..
Yes, I'd say so. Mine was the same after being off the road for a couple of months.

You must be feeling very pleased with yourself Martin.

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Old 6th June 2020, 13:52   #79
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I have never been entirely convinced by the chemical testers either.
It's always a question of degree or concentration. These so-called 'block testers' rely on detecting carbon dioxide from the exhaust gas dissolved in coolant. In an obvious/severe case of HGF, exhaust gas will bubble continuously through the header tank, so you know anyway. In less obvious situations, CO2 has to be desorbed from the coolant and into the test solution in sufficient quantity to reduce the pH. There has to be enough to flip the colour of the indicator (due to acidity). So, a very small long term exhaust leak may not increase the concentration enough. The gas level is very low because of ongoing thermal desorbtion and venting, coolant changes, top ups and the like. Basically, the test is very prone to false negative results (as in the current case). However, it will never, ever give a false positive. Other factors also affect the reliability, like reagent freshness, the operator's competence and using reliable hardware. As with many engine issues, it's just one diagnostic among several. For me, the long term coolant loss and black oil clinched it.


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Old 6th June 2020, 17:26   #80
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Congratulations.
Next time you remove the heads use a an engine crane. Hope you never have to though.
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