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Head Gasket Leak

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#1 sam138


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Posted 10 August 2019 - 09:22 PM

I've changed my 1275  head with a stage 3 unit and I've tried refitting this up twice now and on both times it has leaked and caused it to blow between cylinder 2/3 on first fit up and second time started to burn again between 2/3 and even though it had not blown it still was only running on 2 cylinders. 


I've used a bk450 head gasket both times and torqued down to require setting as per Haynes manual. 


The rebuilt 1275 was running fine prior to the head change over so I can only assume it's down to the head itself. Could it possible be due to the flatness of the head ? 


I've attached a few pictures to confirm if installed the head gasket the correct way around and to show the after effect. As soon as the radiator is filled up you can see the coolant drip out the front of the head even before the engine is switched on. 



Any ideas please ?


Attached File  2.jpg   108.69K   11 downloads


Attached File  3.jpg   91.04K   16 downloads


 Attached File  1.jpg   114.33K   12 downloads

#2 jonjosar


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Posted 10 August 2019 - 10:01 PM

Hi there, Its hard to determine the cause without checking the head for trueness. I would be inclined to take it to an engineering shop and have them check it for you with a view to having a slight skim.

Looking at the picture of the head, it does look like its has a fair bit sanding. The coolant holes look "rounded". If you look close enough, there looks to be a bit of pitting on the face as well.

Do you know the history of the head before you bought it? Its not a good idea to sand the old gasket off.

#3 Dusky


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Posted 11 August 2019 - 09:45 AM

I've heard of this happen, never experienced it myself though. Some say you need to run the engine dry for about 30 seconds before filling with coolant, or fill with plain water first and then add antifreeze later.

#4 rww


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Posted 11 August 2019 - 10:15 AM

Assuming, from what you have stated, that the engine/block ran ok with the previous cylinder head and did not leak then I'm afraid the new head is suspect. You need to get it checked for a flat surface at a machine shop that can also do the minimum of machining to make true. You will have to remove the valves to enable cleaning of the head after the machine shop has finished it's work. If you tell us where you are based you will hopefully get some recommendations as to where this work can be carried out.

#5 sam138


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Posted 11 August 2019 - 05:14 PM

Thanks for the reply’s, I’ll look to get the head over to a machine shop.

Any recommendations for the Hertfordshire area ? I’m also around Buckinghamshire area for work.

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