1500 yanmar 2tr15 engine head torque

[mica]

Need to know what sequence and torque on head bolts and the
torque starting at the lower seting to the final torque on the head bolts

 

[NTEXSAM]

THE HEAD BOLTS TIGHTEN TO 130 FT/LBS. START ON THE INSIDE WORK OUT. MY BOOK DOESNT SAY IN STAGES SO I ASSUME IT MEANS 130 TO START. SAM

 

[RobJ]

Always IMO a good idea to start in stages anyway.

 

[MJPetersen]

Yes in stages usually about 3 stages. You start in the middle and work in a circular pattern through each of the stages until the proper torque is reached.

Mike

 

[California]

Then repeat it again in the evening. And once more in the morning, before you install the rocker shaft or anything that blocks access to the bolts.

I've occasionally found substantial slack this way. This is cheap insurance against repeating the project a month later.

 

[RobJ]

Then repeat it again in the evening. And once more in the morning, before you install the rocker shaft or anything that blocks access to the bolts.

I've occasionally found substantial slack this way. This is cheap insurance against repeating the project a month later.

Ok I'm NOT flaming or being mean or anything like that, but I use to be a mechanic and never ever knew anyone then or now that did this. If you were bolting on heads at 8:30am, then the engine could(should have...being paid by the hour) be running by noon. I'm not saying this will hurt anything, just saying I haven't known any pro to actually do this. JMHO.

I will add to check the repair manual, some engines require new head bolts each and every time. I don't agree(understand) with this either but I do follow the manual. Almost sounds like a money grab. On the engines I rebuilt, the only required bolt to replace was the rod bolts. This was on german engines and everything was torqued via stretch bolts and degrees, IE not ft-lbs of torque.

 

[California]

Well that's a belt-n-suspenders approach, maybe overly cautious, but I've found head bolts 15 ft lbs down, maybe a quarter turn, after a couple of hours. I don't know if that is enough to make the head gasket let go a year later but its easy to take the extra step.

Some of the parts now imported to maintain these antiques are replicas of unknown origin, so I would try to enhance the quality of the job by any way that ocurred to me. I suppose a single repeat after settling overnight is sufficient.

 

[MJPetersen]

I would add that after you run it a few hours--2-5--that it is highly recommended that you re-torque the head bolts using the same pattern. automotive head gasket generally do not require this, but most others do.

Mike

 

[SailorBob]

I would add that after you run it a few hours--2-5--that it is highly recommended that you re-torque the head bolts using the same pattern. automotive head gasket generally do not require this, but most others do.

Mike

I did that after I rebuilt my engine. A couple of them needed to tightned about 1/4 turn. I also initially tightned the nut in by 3rds as well.

 

[1danny]

Need to know what sequence and torque on head bolts and the
torque starting at the lower seting to the final torque on the head bolts

The final torque is 114 -116 lbs. This is the way we do them 40lbs-60lbs-80lbs and then 114-116lbs. The Rocker arm support 58-72lbs. Rods 33-36lbs.

Danny

 

[RobJ]

I would add that after you run it a few hours--2-5--that it is highly recommended that you re-torque the head bolts using the same pattern. automotive head gasket generally do not require this, but most others do.

Mike

I wonder who highly recommended this? And how is an automotive gasket different?

And did you take your tractor back to the dealer after 2-5 hours of running to have them re-tighten the head bolts.

Gentlemen, this is really not needed. Ok I'll leave it alone now.

 

[RobJ]

The final torque is 114 -116 lbs. This is the way we do them 40lbs-60lbs-80lbs and then 114-116lbs. The Rocker arm support 58-72lbs. Rods 33-36lbs.

Danny

Danny is that rocker arm torque specs right out of the manuel? It looked high so I compared to my L, it's 23.5-27.5, the bolt is a M8x1.25(listed as Rocker Arm Bracket). This is probably a standard torque for a M8 bolt.

ROb

 

[MJPetersen]

Most automotive head gaskets are of the style of construction that does not need to be torqued after it has run for awhile. However, most head gaskets in other applications include in the installation instructions that it is necessary to re-torque after 2-5 hours of running. What happens is that the material used in the gasket takes a "set" with the pressure and heat and the bolts loosen.

Will the engine blow up or have a shorter life if you do not--No, but it may develop leaks more easily.

An appropriate analogy can be made with a radiator hose and a worm style hose clamp. After awhile the clamp, which was tight when installed on the new hose will start to leak if you do not re-tighten the clamp. This is why spring clamps are recommended on most light aircraft. They continually tighten compensating for the set in the hose.

Mike

 

[RobJ]

Danny is that rocker arm torque specs right out of the manuel? It looked high so I compared to my L, it's 23.5-27.5, the bolt is a M8x1.25(listed as Rocker Arm Bracket). This is probably a standard torque for a M8 bolt.

ROb

Correction, the 23.5-27.5 is NM, ft-lbs is 17.4-20.3 for the M8 nuts.

Rob

 

[ericofangers]

The final torque is 114 -116 lbs. This is the way we do them 40lbs-60lbs-80lbs and then 114-116lbs. The Rocker arm support 58-72lbs. Rods 33-36lbs.

Danny

hi, my name is eric .
One of my friend is searching for those torques but, when you say lbs, does it mean ft lbs or something else ?

If you had the entire repair book, would you mind to email it to me ?

thanks for your answers.