r100gs Posted December 31, 2015 Report Share Posted December 31, 2015 I installed a Low Compression Head from S3 on my 2013 ST300. I am now having coolant leak from around the six copper washers under the six head bolts. At reassembly: I did NOT use Loctite on the bolts, I reused the six copper washers, I heated the copper washers with a torch (the washers were laid flat on my concrete garage floor) until red hot, I used a top quality torque wrench and tightened the bolts in multiple steps using the crisscross sequence until tight at 84 in/lbs. I ran the bike the first day for 20-30 minutes and all appeared okay. The next time I looked at the bike I saw coolant at a couple head bolts. I started the bike and then saw more coolant leaking from multiple head bolts. I shut off the bike and found the head bolts to be loose. I tightened each bolt as best I could without removing the air box, radiator and other parts. I then rode the bike for 30-40 minutes without any more coolant leakage that night. The next day I checked again and found the head bolts to be loose and coolant around multiple head bolts. I have tried to search the forums for a solution and found one result but I could not determine the fix by reading that search result. Thanks in advance for the advise, critique, help, etc. Happy New Year to all, Chuck Quote Link to comment Share on other sites More sharing options...
collyolly Posted December 31, 2015 Report Share Posted December 31, 2015 Where did you find the head bolt torque figure, it sounds very low to me. Quote Link to comment Share on other sites More sharing options...
micm Posted December 31, 2015 Report Share Posted December 31, 2015 Did you change the o rings? Even if they look OK they can still be knackered and the effect will be the same, the coolant weeping out. Quote Link to comment Share on other sites More sharing options...
r100gs Posted December 31, 2015 Author Report Share Posted December 31, 2015 *Where did you find the head bolt torque figure, it sounds very low to me- Page 29 of the "Sherco Top End Maintenance Manual" and Cylinder Head[nuts or bolts] 7 lb/ft, 84 lb/in (10 n/m) from Copemech. *Did you change the o rings? - No. The new Head came with a new "o" ring that I did use, but I used the original larger outer "o"ring as I did not get a replacement "o" ring with the order. *short allen key- my head bolts are 8mm hex head bolts that screw down into the cylinder. I did use a small 8mm wrench and a 1/4" socket wrench to retighten the bolts after the first leaks. http://www.shercousa...t2.cfm?action=9 This Link has the listing of Sherco Manuals and Parts up through 2014 and at the bottom of the page is the Link to the "Sherco Top End Maintenance Manual". Page 17 of this Manual shows on Picture 24 small "o" rings for each of the six head bolt studs. My head bolts did not have these "o" rings. I tried calling RYP today but they are probably out for the weekend. I will send them an email to see if I should have these smaller "o"rings. I will probably retighten the bolts the next chance I have. That might be a few days from now though. I will post RYP,s response next week and /or give future updates as I work on the problem. Thanks, Chuck Quote Link to comment Share on other sites More sharing options...
dick Posted December 31, 2015 Report Share Posted December 31, 2015 To anneal any solid copper item, I do solid copper head gaskets on the ould bikes, ye need to hang 'em from a loop of wire in order to get to cherry red right through, then quench the item immediately in cold water. You have inadvertently put hard washers back on. Dick. 1 Quote Link to comment Share on other sites More sharing options...
r100gs Posted December 31, 2015 Author Report Share Posted December 31, 2015 To anneal any solid copper item, I do solid copper head gaskets on the ould bikes, ye need to hang and#39;em from a loop of wire in order to get to cherry red right through, then quench the item immediately in cold water. You have inadvertently put hard washers back on. Dick. Could I remove the copper washers, do the process correctly and then expect the washers to work properly or should I get new washers? Quote Link to comment Share on other sites More sharing options...
r100gs Posted December 31, 2015 Author Report Share Posted December 31, 2015 That 2003 cylinder has studs in it that have o rings on ,where as the design of your cylinder has female threads for a retaining bolt that passes through the head if there should be o rings on those bolts then you should have a shallow recess in the cylinder or the head in which they sit in order that they can form a seal. I will look at the stock head. The cylinder top is flat with no recesses. I will take the top back off to confirm what I recall. Thanks again Quote Link to comment Share on other sites More sharing options...
lineaway Posted January 1, 2016 Report Share Posted January 1, 2016 10nm = 89 lb/in I would get new washers and O-rings from Ryan and do 90 inch lbs and call it good. Quote Link to comment Share on other sites More sharing options...
r100gs Posted January 1, 2016 Author Report Share Posted January 1, 2016 10nm = 89 lb/in I would get new washers and O-rings from Ryan and do 90 inch lbs and call it good. That is what I will do. I removed the bolts and washers this evening. I will get some silicone grease also. Should I put Blue Loctite on the bolts? Quote Link to comment Share on other sites More sharing options...
r100gs Posted January 2, 2016 Author Report Share Posted January 2, 2016 Just had a thought,if your head bolts are too long or the copper washers are too thin; then what could happen is that the head bolts will reach the bottom of the blind retainer hole and tighten against that and not against the copper washer properly. This may be caused by an error in the casting/machining process that would not be noticeable on a visual inspection but is a quick fix by shortening the head bolts a little. I am not saying that this is your problem; but that if the leaking of coolant persists after fitting the 2 new o rings and new copper washers; then this would be something to investigate. Quote Link to comment Share on other sites More sharing options...
lineaway Posted January 3, 2016 Report Share Posted January 3, 2016 It seems most products come with little or no directions nowadays. I like the bolt length idea. It would be very easy to check just by a head to head comparison. Quote Link to comment Share on other sites More sharing options...
steve_earle Posted January 3, 2016 Report Share Posted January 3, 2016 I found the same problem when putting an S3 head on a Sherco, The bolts are a smidge too long, A quick trip to the bench grinder and take 1mm ish off done the trick. Quote Link to comment Share on other sites More sharing options...
r100gs Posted January 4, 2016 Author Report Share Posted January 4, 2016 The bolt length appears to be correct. I put a couple bolts in without the washers and did not have the bolts bottom out. I have a few parts that need ordered so I will get replacement copper washers with the order. I was at the TSC hardware today and saw a package of Nitrile "o" rings 1/16" thick x 5/32 ID x 9/32 OD. I put these under the old copper washers and carefully tightened the bolts, put the bike back together and went for a 15 minute ride. As of this evening no coolant has leaked. I will recheck the bolts tomorrow and report back. Quote Link to comment Share on other sites More sharing options...
crazybond700 Posted January 4, 2016 Report Share Posted January 4, 2016 You mention the bolds come loose, so a leak is logical then. So the problem must be in the bolds or your tightning? Quote Link to comment Share on other sites More sharing options...
r100gs Posted January 5, 2016 Author Report Share Posted January 5, 2016 I will take a small amount off each bolt with the new crush washers. Since the coolant is not leaking now I will procrastinate until I have a larger order for RYP. Quote Link to comment Share on other sites More sharing options...
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