rob m Posted June 22, 2015 Report Share Posted June 22, 2015 (edited) I wasn't sure if this should go in here or the twin shock but no doubt there will be a responsible adult to keep my right! I have taken the head off my 1972 t250 as it was blowing a little....well, a lot actually. All looks OK but I'm struggling to find the correct torque settings for the 4 nuts and 2 bolts. I've tried the search function but I keep finding the same posts for a different engine, perhaps I'm not using the correct key words. Any help or a point in the right direction (other than saying, "buy a manual") would be appreciated. . . . . I will buy one eventually though Edited June 22, 2015 by rob m Quote Link to comment Share on other sites More sharing options...
lbhbul Posted June 22, 2015 Report Share Posted June 22, 2015 Rob, Welcome first! If you are referring to a 1972 Mod 91 ( engine s/n 91xxxx) Then a safe nbr that I use is 12 to 14 ft lbs. I don't have my manual at hand but you will be safe there as I use it for all my work. Larry Quote Link to comment Share on other sites More sharing options...
rob m Posted June 23, 2015 Author Report Share Posted June 23, 2015 Thanks Larry, I believe mine to be a model 80 (eng s/n M-800****) what you recommend seems to be in the ballpark with other figures I've seen quoted for some other engines so I'll give that a go. Thanks again, Rob. Quote Link to comment Share on other sites More sharing options...
johnjsy Posted June 23, 2015 Report Share Posted June 23, 2015 Hullo Rob M,I may be able to help you. First off,the head may be warped a bit from uneven tightening. Put a little fine grinding paste,plus a little light oil or paraffin on to the head to barrel sealing face & lap the joint to get a perfect even contact all round. Be extra careful not let any get onto the piston or down the side of the bore. Cleanliness is of the essence here! Next,find a piece of paper or card about 4 inches square-- not critical-- then draw a nice circle. Put a dot or an X at 10 o'clock then 2 o'clock then at 4 then 8 . O.k.? Next one at 12 a bit higher up then at 6 down lower. You now have a pattern of the cylinder head studs. I now give you the tightening sequence,put number 1 by 2o'clock --2 by 8o'clock--3 by 4o'clock--4by 10 o'clock--5at the bottom by 6 o'clock & 6 by 12 o'clock. I have a low reading torque wrench & start off at 4 ft lbs & go up in steps of 2 ft lbs. Studs one to four should end at 14 ft lbs & five & six a bit lower at 11 ft lbs. I have been doing it this way for years on many different motors with no problems. Just to mention,when taking off a head,release each nut a little at a time in the same sequence,also I assume you have the correct thick washers under each nut? If not,try & get some,or make some,it is important. Hope this helps,John. Quote Link to comment Share on other sites More sharing options...
lbhbul Posted June 23, 2015 Report Share Posted June 23, 2015 Rob, mod 80 Bultaco has a counter bored head and a raised liner and does not require a gasket or sealer, if the head continues to seep, it will have to be machined or replaced. Seepage is dirty not life threating. Larry Quote Link to comment Share on other sites More sharing options...
rob m Posted June 23, 2015 Author Report Share Posted June 23, 2015 Thanks for the feedback chaps, all advice is greatly appreciated. lbhbul, thats my engine all right and it all "looks" OK but since I'm off on holiday at the weekend I'll order new nuts, bolts and washers and fit them on my return. Quote Link to comment Share on other sites More sharing options...
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