Peter Cobbold Posted May 20, 2014 Report Share Posted May 20, 2014 (edited) Thanks Peter, I have removed all of the gasket but there are some carbon marks between the bores etc where the gasket was blown, will the meths clean that off or should I not worry to much about discolouration. Thats the critical area. I myself would go very carefully with a wooden scraper so as not to dig in. Maybe fine wet and dry folded over the scraper, very lightly done. There is a possibility that the combustion gases have eroded the block locally so you do not want to make that worse. But I cant see leaving the carbon is an option. A photo of discolouration might help. Best wait until a real expert comes along before tackling that area !! - and how to check it for flatness - straightedge? plastigauge? Peter Edited May 20, 2014 by Peter Cobbold Quote Link to post Share on other sites
John L Posted May 21, 2014 Report Share Posted May 21, 2014 While you still have the head off it would be good to check the timing mark on the crank pulley, use the DTI on #1 piston. J Quote Link to post Share on other sites
Kevo_6 Posted May 21, 2014 Author Report Share Posted May 21, 2014 Thats the critical area. I myself would go very carefully with a wooden scraper so as not to dig in. Maybe fine wet and dry folded over the scraper, very lightly done. There is a possibility that the combustion gases have eroded the block locally so you do not want to make that worse. But I cant see leaving the carbon is an option. A photo of discolouration might help. Best wait until a real expert comes along before tackling that area !! - and how to check it for flatness - straightedge? plastigauge? Peter Thanks Peter While you still have the head off it would be good to check the timing mark on the crank pulley, use the DTI on #1 piston. J Thanks John, yes I have that in hand to do. I have checked previously with a piston stop but the DTI would be more accurate. Quote Link to post Share on other sites
Peter Cobbold Posted May 21, 2014 Report Share Posted May 21, 2014 (edited) Plastigauge: http://plastigauge.co.uk/ I think I would test the gap between cylinders with a strip of plastigauge along each land. Trial fit the head, no gasket. Examine the guage - it it is waisted in the middle the key will tell you how much depth has been lost. Hopefully it will spread uniformly, indicating no metal erosion. Mind you I've never actually done it, but cant see why it shouldnt work... Peter Edited May 21, 2014 by Peter Cobbold Quote Link to post Share on other sites
Kevo_6 Posted May 21, 2014 Author Report Share Posted May 21, 2014 Plastigauge: http://plastigauge.co.uk/ I think I would test the gap between cylinders with a strip of plastigauge along each land. Trial fit the head, no gasket. Examine the guage - it it is waisted in the middle the key will tell you how much depth has been lost. Hopefully it will spread uniformly, indicating no metal erosion. Mind you I've never actually done it, but cant see why it shouldnt work... Peter Hi Peter, I had a good clean again as you suggested with white spirit & meths and its coming up really clean. I think I may of panicked a wee bit, a bit more elbow grease and I will be good to go. One more question is when I put the studs back in do I just do them finger tight? Quote Link to post Share on other sites
Guest ntc Posted May 21, 2014 Report Share Posted May 21, 2014 Kevo Now is the time to look for small cracks around the block where the studs go.Also look for stretched studs or they will fail. Quote Link to post Share on other sites
Kevo_6 Posted May 21, 2014 Author Report Share Posted May 21, 2014 Hi Neil, thanks I will have a good look for cracks tomorrow. The studs look in good shape and relitivly easy to remove, is there a measurement I can refer to to check against for stretching? Quote Link to post Share on other sites
Guest ntc Posted May 21, 2014 Report Share Posted May 21, 2014 Kevo You will see it in the threads and look for corrosion in the studs if in doubt replace the lot and we will take it from there. Quote Link to post Share on other sites
Grinnal Posted May 22, 2014 Report Share Posted May 22, 2014 Hi I know this sounds drastic but if your head is no converted to unleaded it could be bad value seals. Do compressions test; this will help establish if you have weak compression on cylinders. Mike Quote Link to post Share on other sites
Peter Cobbold Posted May 22, 2014 Report Share Posted May 22, 2014 Hi Peter, I had a good clean again as you suggested with white spirit & meths and its coming up really clean. I think I may of panicked a wee bit, a bit more elbow grease and I will be good to go. One more question is when I put the studs back in do I just do them finger tight? I do mine as tight as they'll go by hand, dry. Dont know if that's right....but it has worked for me. Its very important that the drillings the studs screw into have not got fluid hiding in them - oil etc. Tightening the head nuts can then burst the block with hydrauilc pressure as the stud turns and tries to compress the liquid. Peter Quote Link to post Share on other sites
Kevo_6 Posted May 22, 2014 Author Report Share Posted May 22, 2014 Hi I know this sounds drastic but if your head is no converted to unleaded it could be bad value seals. Do compressions test; this will help establish if you have weak compression on cylinders. Mike Thanks Mike but heads off as gasket was gone, Head is being unleaded new valves, guides and seats etc. I do mine as tight as they'll go by hand, dry. Dont know if that's right....but it has worked for me. Its very important that the drillings the studs screw into have not got fluid hiding in them - oil etc. Tightening the head nuts can then burst the block with hydrauilc pressure as the stud turns and tries to compress the liquid. Peter Will do Peter thanks Kevo You will see it in the threads and look for corrosion in the studs if in doubt replace the lot and we will take it from there. Thanks Neil, I will give them a check. Quote Link to post Share on other sites
Kevo_6 Posted May 23, 2014 Author Report Share Posted May 23, 2014 Kevo You will see it in the threads and look for corrosion in the studs if in doubt replace the lot and we will take it from there. Neil The studs look really good & I have had a good look at the block and I can't see any cracks. I have picked up the head this afternoon , so l will start reassembly this weekend . Quote Link to post Share on other sites
Kevo_6 Posted June 22, 2014 Author Report Share Posted June 22, 2014 (edited) Yipeeeeeee It's all back together and running nicely, about bl@@dy time I hear you all say. Went for a run yesterday, no more pinking & lumpyness. My thanks to all for your time & patience. Going for another shakedown run this afternoon, just got to replace the water now with anti freeze mixture this morning. So far no leaks!!!!!! P.S do I retouque after few hundred miles? Edited June 22, 2014 by Kevo_6 Quote Link to post Share on other sites
Andrew Smith Posted June 22, 2014 Report Share Posted June 22, 2014 (edited) Well done for cracking the 'battle for supremacy' code Kev - a re-torque Edit: wouldn't hurt; I must still be on Italian time - albeit only one hour in advance! Cheers Andrew Edited June 22, 2014 by Andrew Smith Quote Link to post Share on other sites
Peter Cobbold Posted June 22, 2014 Report Share Posted June 22, 2014 I would retorque now. Peter Quote Link to post Share on other sites
littlejim Posted June 22, 2014 Report Share Posted June 22, 2014 Based on a 4A, I would do what Peter and Andrew recommend. After my refurb, the new head gasket blew while I was waiting for the "book' miles to come up. With the next head gasket, I retorqued the head bolts (with tappets off) after a few hundred K's. Still going strong. Quote Link to post Share on other sites
Kevo_6 Posted June 23, 2014 Author Report Share Posted June 23, 2014 Well done for cracking the 'battle for supremacy' code Kev - a re-torque Edit: wouldn't hurt; I must still be on Italian time - albeit only one hour in advance! Cheers Andrew Cheers Andrew, it was a long time coming, hope you had a great time in Italy. I would retorque now. Peter Thanks Peter Based on a 4A, I would do what Peter and Andrew recommend. After my refurb, the new head gasket blew while I was waiting for the "book' miles to come up. With the next head gasket, I retorqued the head bolts (with tappets off) after a few hundred K's. Still going strong. I will retorque every thing this week. What do you guys do, back off 10lbs and then retorque to 80lbs in the correct sequence? Quote Link to post Share on other sites
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