Small headbolt torque

[Patrick 1068]

Hello All,
I had to repair the head on my 186d, and I found the torque specs for the eight large head bolts which is 79 lbft if I'm not mistaken, but I cannot however find the torque specs for the three smaller bolts that surround the push rods. Does anyone happen to know the specs?
This is the old school repair that I had to do because I can't find a used head for it for less than $1,200. Hopefully this works!

 

[careyo63]

0.9L 3Cyl. 3 Assist bolts 20 Ft. Lbs.

 

[bindian]

Where is the head of that screw going when it breaks off?
hugs, Brandi

 

[Patrick 1068]

0.9L 3Cyl. 3 Assist bolts 20 Ft. Lbs.

Thank you very much. I can now reassemble and see if my old school cold weld will hold.

 

[Patrick 1068]

Where is the head of that screw going when it breaks off?
hugs, Brandi

Through the injector hole and onto the bench

 

[bindian]

Oh, the last photo didn't load last night, so it looked like the head was left intact. I read about the cold weld repairs like that in Antique Power magazine.
hugs, Brandi

 

[Doughknob]

It will run better than before. But only for a short while. crack still there in valve seat and soft brass filler will not last long……. Good luck.

 

[etpm]

Greetings Patrick,
I had never heard of this "cold weld" repair technique before your post. It looks like, from your pictures, that the crack in the valve seat is still present. If the compressed gases can't leak through the crack anywhere but into the manifold then I suppose your repair might work. The compression will be lower in that cylinder but the crack in the seat looks fairly small so maybe it won't be very much. I don't know how long such a repair might work, if the crack will continue to propagate, and just how much compression loss there will be from the crack in the seat but I am really curious. Please let us all know how well your repair works and for how long.
Good Luck,
Eric

 

[etpm]

Oh, the last photo didn't load last night, so it looked like the head was left intact. I read about the cold weld repairs like that in Antique Power magazine.
hugs, Brandi

Greetings Brandi,
I searched online the Antique Power Magazine for cold welding cast iron and no luck. Can you provide any more info on the technique?
Thanks Much,
Eric

 

[etpm]

Through the injector hole and onto the bench

Say Patrick,
I looked online and wasn't able to find any info on the technique you used. By technique I mean using brass screws to repair the crack in a cast iron head. Actually, not even using brass screws for any type of cold welding cast iron cracks. I do know about products like Stitch N' Weld. But your exact method I can't find anything about and I'm really curious about it. Any sources you can share I would really appreciate.
Thanks,
Eric

 

[bindian]

Eric, I think this is it.

Advanced marine repair solutions - Wärtsilä

Wärtsilä’s repair services for large commercial vessels: in-situ machining, reconditioning, metal stitching. Formerly offered by QuantiServ and Lock-N-Stitch.

www.locknstitch.com

I gave my first issue with the article to a friend. This is the issue https://ertelgiftshop.com/antique-power/antique-power-may-jun-2022
This is the article name and author....

• A Stitch in Time
  Cold repair for broken cast iron
  text by Rick Mannen

It is a fascinating process to read about.
hugs, Brandi

 

[ponytug]

Lock-n-Stitch is a different technique, using steel (or aluminum in aluminum parts) bolts, and repeated drilling that make a very strong, gas tight repair. There is a fun YouTube video here;

I have never seen a brass screw used to fix (braze?) cast iron. I find it hard to imagine it has much strength, so I am interested to see how it works out. @Patrick 1068 I hope it was worth your while. Thanks for sharing it.

All the best,

Peter

 

[bmaverick]

Hello All,
I had to repair the head on my 186d, and I found the torque specs for the eight large head bolts which is 79 lbft if I'm not mistaken, but I cannot however find the torque specs for the three smaller bolts that surround the push rods. Does anyone happen to know the specs?
This is the old school repair that I had to do because I can't find a used head for it for less than $1,200. Hopefully this works!View attachment 747058View attachment 747058View attachment 747058View attachment 747059

See attached

 

[careyo63]

At least it's not in japanese. Close though.