doe70 Posted October 10, 2011 Share Posted October 10, 2011 Gday,Ive got the heads off my C motor and have ordered standard gaskets but looking at how much the cylinder liners sit proud of block (about .050") cant see how ill get much compression on gasket when bolted down. Heads have small shallow grooves cut into them but still doesnt look right? What is the norm, and what do the fire-ring heads look like? any ideas? i dont want to bolt them down if wrong gasket...cheers ellis Quote Link to comment Share on other sites More sharing options...
Freightrain Posted October 13, 2011 Share Posted October 13, 2011 How thick are the gaskets when new? Quote Larry 1959 B61 Liv'n Large...................... Charter member of the "MACK PACK" Link to comment Share on other sites More sharing options...
doe70 Posted October 16, 2011 Author Share Posted October 16, 2011 Gday Larry, the new ones are about 1/16" thick, maybe a tad under, they consist of two layers of copper. the old ones were material not copper. im going to have a crack at putting heads back on later in week if all goes to plan.cheers Quote Link to comment Share on other sites More sharing options...
Maddog13407 Posted October 18, 2011 Share Posted October 18, 2011 fire ring gaskets were not coppers at all. more like a heavy felt gray material and fire rings are in the package also. most of the newer 711's end707;s and end673b and c engines had the fire rings i believe. sounds like you have the wrong gaskets and need the ones with the fire rings. do your head have the fire rings on them now? when you remove the head usually the fire rings are stuck to the bottom of the head. matt Quote Link to comment Share on other sites More sharing options...
doe70 Posted October 18, 2011 Author Share Posted October 18, 2011 the old ones were an orange hard fibre material type gasket and there were rings left stuck around lip of liners on block. i went back to mack and they said the gaskets ive now got are the only ones showing up for the c motor, that the rings are part of the gasket???? gaskets look like theyd work but is more confusing than anything else ive worked on..ellis Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted October 19, 2011 Share Posted October 19, 2011 I can tell you what i remenber about them but have not been in one in the last thrity years. The 673c came from the factory with non maxidyne head gaskets and liners. The top of the liner was flat.When most guys overhauled they went back with the maxidyne liner and had the groves cut in the head surface.The maxidyne liner will have a step or bead in the top and will not be flat like the standard liner. It is good for more pressure and the head gasket will have a fire ring in the pakage that is set on top of the liner and is a flat metal ring.But i have never seen a 711 or 707 engine with the fire rings or maxidyne head gaskets.I do not remenber the liner protruion and have not got a old manual but would not go back untill i checked the liner protrion. That is done by measuring from the top of the liner (flat part) and not the very top that sticks up and to the top of the block.There is some mack dealer guys on here that can look this up for you. Quote glenn akers Link to comment Share on other sites More sharing options...
rhasler Posted October 20, 2011 Share Posted October 20, 2011 The E6 2 valve specs say:Liner, Flange Extension Above Deck — Beaded without Fire Ring 0.0035–0.0075 Flat, without Fire Ring 0.0005–0.0035 Here's a picture of what Theakerstwo referred to Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
doe70 Posted October 20, 2011 Author Share Posted October 20, 2011 thanks for input, still not 100% sure what im looking at, mine is same as middle pic, beaded i guess and measures0.004 - 0.006 from flat deck (number 2.) to (number 3.) The gaskets ive got are fel-pro brand no 8197C for end673, end673T, end711, endL711 (20 stud holes for 5/8" diam studs. But as said they dont have a separate fire-ring, and i pulled rings off my old block? mack again tell me ive got the right gaskets?? any further input appreciated.cheers ellis Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted October 23, 2011 Share Posted October 23, 2011 Mack cant tell you what liner that is in it now.You have to look at the drawing that was posted and find which liner you have in it now and not what was in it when new. Also some one may have install wrong gasket before so find what liner you have. Is it the flat top or the one that has the step in the top like the middle drawing?If the top is flat like shown in the top drawing then dont use a gasket that uses a fire ring and dont listen to a parts man trying to tell you what you need. The liner is probly older than the parts man anyway. glenn Quote glenn akers Link to comment Share on other sites More sharing options...
Maddog13407 Posted October 23, 2011 Share Posted October 23, 2011 i believe you have the wrong gaskets. my end707 diesel has the firerings in the gasket and gaskets were the felt material not coper. actually the old gaskets i took off i checked the part number and they are the same gaskets as a maxidyne 237 gasket. i think some 711's and 673b and c engines used this gasket. when i took the heads off of my engine the firerings were still stuck to the bottom of the heads. i hit them with a screwdriver and they popped right off, checked the number and ordered new gaskets and they were maxidyne gaskets. i can probably find you the part number if youd like. Matt Quote Link to comment Share on other sites More sharing options...
doe70 Posted October 23, 2011 Author Share Posted October 23, 2011 Gday fellas, think you were all pretty much right, mine has the stepped liner and meant to have firerings, mack mechanic said it must have been altered from original as the c motors came out without fire-ring set up - and motor was a service unit put in at later stage. have the right gaskets as said from a 237, they are a lot cheaper but now mack saying as its taken longer than two wks to sort out & might not be able to refund the difference as they dont sell them all too often, reckons last time he sold one here was 2002.. time will tell but at least i can go ahead and bolt her back together, im aiming to use hylomar (not sure of spelling) and same mech said should put some loctite 515 around water galleys as they had one leak yrs ago and thats what they do now? any ideas on that, guess if theyre doing it...cheers ellis Quote Link to comment Share on other sites More sharing options...
Rob Posted October 23, 2011 Share Posted October 23, 2011 Gday fellas, think you were all pretty much right, mine has the stepped liner and meant to have firerings, mack mechanic said it must have been altered from original as the c motors came out without fire-ring set up - and motor was a service unit put in at later stage. have the right gaskets as said from a 237, they are a lot cheaper but now mack saying as its taken longer than two wks to sort out & might not be able to refund the difference as they dont sell them all too often, reckons last time he sold one here was 2002.. time will tell but at least i can go ahead and bolt her back together, im aiming to use hylomar (not sure of spelling) and same mech said should put some loctite 515 around water galleys as they had one leak yrs ago and thats what they do now? any ideas on that, guess if theyre doing it...cheers ellisYes, some type of sealant on any bolt or fasteners that pass through into a water jacket is a good idea to prevent leaks.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
Rob Posted October 23, 2011 Share Posted October 23, 2011 The aftermarket rebuild kits one can purchase now have the stepped liner and you need to have the heads grooved for fire rings. They are referred to as a "Maxidyne" conversion.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.