Thermodyne Head

[M54A1]

I have a small oil seep from the back head gasket on my ENDT-673, I retorqued the head using the torque specs for an E6 that my mack dealer had given me, but the sequence showed 20 studs, where as my thermodyne has 18 studs. The E6 also calls for 185ft/lbs on the studs, is this also correct for the ENDT-673.

Thanks

[ThaddeusW]

I have a small oil seep from the back head gasket on my ENDT-673, I retorqued the head using the torque specs for an E6 that my mack dealer had given me, but the sequence showed 20 studs, where as my thermodyne has 18 studs. The E6 also calls for 185ft/lbs on the studs, is this also correct for the ENDT-673.

Thanks

There were about three different revisions for the 673. Perhaps you have one of an earlier design?

[Mike]

I have a small oil seep from the back head gasket on my ENDT-673, I retorqued the head using the torque specs for an E6 that my mack dealer had given me, but the sequence showed 20 studs, where as my thermodyne has 18 studs. The E6 also calls for 185ft/lbs on the studs, is this also correct for the ENDT-673.

Thanks

Jase,

I'm not at home where my manual is at. It sounds right to me but I hate guessing. I hope someone see's this and sends you the correct specs soon before you get too involved. I'm at my g/f house on her computer and will get back late this afternoon. I will check back.

mike

[theakerstwo]

The endt673 with 18 5/8 studs will torque to 175 ft lbs with a mack gasket unless it has been up date in the past years. A after market gasket may require a different torque.A E6 is a long was from a endt673.The later endt673b or c will have 20 bolts and a different torque.But different engine.

[Mike]

The endt673 with 18 5/8 studs will torque to 175 ft lbs with a mack gasket unless it has been up date in the past years. A after market gasket may require a different torque.A E6 is a long was from a endt673.The later endt673b or c will have 20 bolts and a different torque.But different engine.

Hi Glen,

I told him i'd get back to him. I only hope he didn't go ahead with the torque someone else gave him. My 1965 copyright MOTORS MANUAL gives 150lbs. torque for the 673's and 711 engines. And to use oil on the bolts, run up finger tight before using AIR FORCE torque on them. And also use new studs at overhaul. Don't use sealing compound on gaskets. My manual did say to use the latest head gaskets. But did not say it was a Mack OEM gaskets. He may need to get the mike out and see if the thickness is the same

mike

[HK Trucking]

Hi Glen,

I told him i'd get back to him. I only hope he didn't go ahead with the torque someone else gave him. My 1965 copyright MOTORS MANUAL gives 150lbs. torque for the 673's and 711 engines. And to use oil on the bolts, run up finger tight before using AIR FORCE torque on them. And also use new studs at overhaul. Don't use sealing compound on gaskets. My manual did say to use the latest head gaskets. But did not say it was a Mack OEM gaskets. He may need to get the mike out and see if the thickness is the same

mike

Mike, he's just re torquing, not pulling the heads & replacing gaskets.

The ENDT673 had the old type head gaskets without fire rings.

The number that Glenn stated rings a bell with me, and I think I remember the torque on ENDT675 head studs was 185 ft lbs.

ENDT675 and ENDT673B &C were the same heads & gaskets, with the fire rings.

One of these days I gotta dig out all my Mack technical literature that got packed away when I moved a year and a half ago.

.

[Mike]

Mike, he's just re torquing, not pulling the heads & replacing gaskets.

The ENDT673 had the old type head gaskets without fire rings.

The number that Glenn stated rings a bell with me, and I think I remember the torque on ENDT675 head studs was 185 ft lbs.

ENDT675 and ENDT673B &C were the same heads & gaskets, with the fire rings.

One of these days I gotta dig out all my Mack technical literature that got packed away when I moved a year and a half ago.

.

Herb,

I don't think I would retorque a set of heads after they have been disturbed without replacing the gaskets especialy if their is any leakage. And I would rather use the torque settings that Glenn gave because the more quench is much closer than the 150lbs. my manual gave.

While we are on this engine subject. I was trying to change oil for the first time in my END673P today. But looks like the previous owner had the nut so tight that I failed to get it loose. What could the torque be set to get this nut loose? I was using an combination wrench with no luck.

Thanks

mike

[HK Trucking]

Herb,

I don't think I would retorque a set of heads after they have been disturbed without replacing the gaskets especialy if their is any leakage. And I would rather use the torque settings that Glenn gave because the more quench is much closer than the 150lbs. my manual gave.

While we are on this engine subject. I was trying to change oil for the first time in my END673P today. But looks like the previous owner had the nut so tight that I failed to get it loose. What could the torque be set to get this nut loose? I was using an combination wrench with no luck.

Thanks

mike

Yup, If there's oil seeping out between the head and block, I'm not too hopeful that re torquing will help, but that's what the OP's stated intention was.

On your truck, did you mean the oil pan drain plug is so tight it won't budge?

I'd recommend using the proper size 6 point socket with a breaker bar and a pipe on the breaker bar if necessary.

That oil pan bung is usually brazed into those old oil pans, so I wouldn't recommend trying an impact wrench to break it loose, as the bung could be ripped out of the pan.

.

[Mike]

Yup, If there's oil seeping out between the head and block, I'm not too hopeful that re torquing will help, but that's what the OP's stated intention was.

On your truck, did you mean the oil pan drain plug is so tight it won't budge?

I'd recommend using the proper size 6 point socket with a breaker bar and a pipe on the breaker bar if necessary.

That oil pan bung is usually brazed into those old oil pans, so I wouldn't recommend trying an impact wrench to break it loose, as the bung could be ripped out of the pan.

.

Herb,

I just wondered if someone used a torque wrench to tighen the oil pan drain plug. I hope not. I should have built me a pit in the floor of my new garage, but I did not do it. Yes the drain plug is too tight for me to handle. I thought of using a pipe also but will have to find me one this week. And will have to buy me the proper six-point socket for my 1/2 inch socket wrench. I only have the proper size combination wrench at this time.

Thanks for the info its much appreciated.

mike

[M54A1]

Well retorquing slowed the leak down considerably but didn't stop it, I guess I'm going to pull the heads and do it right. Anybody know where to find headgaskets for an ENDT-673, my mack dealer couldn't get them. Thanks for the help!

[HK Trucking]

Well retorquing slowed the leak down considerably but didn't stop it, I guess I'm going to pull the heads and do it right. Anybody know where to find headgaskets for an ENDT-673, my mack dealer couldn't get them. Thanks for the help!

Shoot a PM to Barry on this site. He should be able to get the stuff you need.

.

[theakerstwo]

If the engine has 9/16 studs then it will be torqued to 150 ftlbs.The 18 5/8 studs was at 175 in their day but could have been updated due to newer gaskets.Some of the ENDt 673 a b or c engine did not have fire rins from the factory but could have been updated to the maxidyne gasket that has the fire ring.

[Mack B Mike]

Well retorquing slowed the leak down considerably but didn't stop it, I guess I'm going to pull the heads and do it right. Anybody know where to find headgaskets for an ENDT-673, my mack dealer couldn't get them. Thanks for the help!

Hey Jase

You can get Felpro head gaskets, the number is 2813 i think, i got them for mine when i overhauled my 673 due to a cracked sleeve, pistons,rings and bearings and gaskets are avliable from Mack. i can get you more info if you would like

Mike

Edited September 22, 2009 by Mack B Mike

[M54A1]

Mike if I could find a rebuild kit somewhere it would be great. I have talked to Barry at Watts Mack and he said Mack was out of NOS bearing and rings for the 673T. I just bought a Maxidyne, but would still like to freshen up the Thermodyne as a spare.