Mi16 Head Torque Settings

[chris 417 mi 34 2 Cars]

Anyone advise the torque settings for the head bolts on an early mi16 head ?

 

Been warned away from haynes and cant really find any as such so far

[Ryan 99]

The Pumaracing site suggests doing them up to 75 lbft in three stages (25, 50, 75). The normal way stretches them some ridiculous amount.

[chris 417 mi 34 2 Cars]

Dont suppose you have a link to the site do you ?

[Ryan 99]

http://www.pumaracing.co.uk/pug16v.htm

[petert 586]

I know people who have tried Puma's method and have had weeping head geaskets over time. Your choice, but a set of head bolts isn't very expensive.

 

Stage I - 60Nm

Stage II - slacken, the 20Nm

Stage III - 300 degrees

 

The final stage is easy if you have an engine stand, breaker bar and quality torx socket.

Edited May 12, 2007 by petert

[chris 417 mi 34 2 Cars]

engine is on a stand and i have brand new genuine peugeot head bolts waiting to go on .... is this method 100% for sure then ?

[pug_ham 244 3 Cars]

Like petert says but from Autodata;

Stage 1; 60Nm.

Stage 2; individually slacken off & tighten to 20Nm then 100' + 100' +100' inturn.

 

Graham.

[Mikey S 29 1 Cars]

if you tap the bolt holes and use a litle copper slip on the threads and under the bolt heads they torque down alot easier, especially when you have to angle tighten them

[chris 417 mi 34 2 Cars]

cheers for the replys, head will be going back on tonight.

[James_m 0]

I did mine using the Pumaracing method , and my head gasket blew F1 style today. Not advisable

[James_m 0]

I probably should add the outcome to this defence of Puma's method....

The head gasket did'nt blow, the sensor on the back of the block unwound itself hammering into the bulkhead somewhere, making a horrible metallic noise, and then all the oil getting splashed onto the exhaust manifold led me to beleive the HG had gone.

I thought smoke was leaking out of the back of the headgasket itself somewhere. My bad, and make sure those sensors are done up tight!

It really was F1 style though

Edited May 15, 2007 by James_m

[Richie-Van-GTi 71 2 Cars]

I believe he put the head on last night as per QEP advice which is the same as petert and graham etc.

[matty_gti 20]

I believe he put the head on last night as per QEP advice which is the same as petert and graham etc.

 

I did my 8v head bolts up the same way and one of the bolts stripped out the thread in the block so im considering next doing my headblots up the puma racing way but now im paraniod that there either going to be to tight, or not tight enough!!

[Mikey S 29 1 Cars]

if you tap the bolt holes and use a litle copper slip on the threads and under the bolt heads they torque down alot easier, especially when you have to angle tighten them

 

 

[madvalver 0]

Longmans advised to me go to 65lbft in stages(seemed tight enough). Use gen pug gasket. No idea if mines any good yet as havent run it in anger. But its going to be a track toy so if it go's, its go's!

[jonnie205 1]

the 300 degrees is very scary and has resulted in me snapping one bolt and stripping the block in another. I now go to 80ft lbs in 3 stages and i find this has been fine. The degrees way can be ok but i would go to 200 not 300

Edited May 16, 2007 by jonnie205

[Richie-Van-GTi 71 2 Cars]

Ive done the 300 degree method on a few engines and never had issues with snapped bolts or stripped threads. Ive always used new bolts and copper slip though, as well as cleaning threads before fitting.

[matty_gti 20]

the 300 degrees is very scary and has resulted in me snapping one bolt and stripping the block in another. I now go to 80ft lbs in 3 stages and i find this has been fine. The degrees way can be ok but i would go to 200 not 300

 

I thought giving a little more that 75ft lbs, like 80ft lbs would have been a better option, just that little tighter.

 

Longmans advised to me go to 65lbft in stages(seemed tight enough). Use gen pug gasket. No idea if mines any good yet as havent run it in anger. But its going to be a track toy so if it go's, its go's!

 

But i dont get the "65ft lbs in 3 stages"?...surely that isnt tight enough?

 

Ive done the 300 degree method on a few engines and never had issues with snapped bolts or stripped threads. Ive always used new bolts and copper slip though, as well as cleaning threads before fitting.

 

I cleaned the threads and used the 'modydulihkuawgsfkgqkef' (somthing or rather!) grease it states in the haynes but thats when it strippped the thread.

Edited May 16, 2007 by matty_gti

[James_m 0]

I dont know if the alloy blocks degrade over time, but pretty much all the threads on my block were very weak, with a few stripping.

[petert 586]

That's not a major problem. Just helicoil them if they strip.

[matty_gti 20]

That's not a major problem. Just helicoil them if they strip.

 

But doesnt that leave you a problem when you need to change the HG in future?

[welshpug 1,657]

But doesnt that leave you a problem when you need to change the HG in future?

 

not at all, its simply an insert for the bolt to thread into, many expensive bicycle parts have inserts in alloy parts for bolts to thread into.