Cylinder Head Retorque Question

B

BrioPA

Daily Driver
Installed a MWB head on my '83 X1/9. Finally got the timing set up, and at the point that I have put a few miles on it and need to retorque the head, per the MWB recommendation (they supply regular head bolts, not the factory stretch bolts). I have the special wrench, which should help me reach the bolts in the corners, but with the intake manifold in place, reaching the centre bolt on the intake/exhaust side appears to be almost impossible. Is there some sort of special tool combination that let's me get in there without removing the intake manifold, or do I need to bite the bullet and take it off?

TIA!

Martin
 
BrioPA said:
Installed a MWB head on my '83 X1/9. Finally got the timing set up, and at the point that I have put a few miles on it and need to retorque the head, per the MWB recommendation (they supply regular head bolts, not the factory stretch bolts). I have the special wrench, which should help me reach the bolts in the corners, but with the intake manifold in place, reaching the centre bolt on the intake/exhaust side appears to be almost impossible. Is there some sort of special tool combination that let's me get in there without removing the intake manifold, or do I need to bite the bullet and take it off?

TIA!

Martin
Click to expand...

I think.....your problem is that you need TWO different wrenches to be able to re-torque the head in situ. One of them does the corner bolts - it seems that is the only one you have. But...to do the centre bolts...you need a different wrench. These special wrenches are usually sold as set - like here:

www.midwest-bayless.com

Cylinder Head Wrench Set SOHC 17mm (Fiat Bertone X1/9, Strada/Ritmo/UNO) - OE

Cylinder Head Wrench Set SOHC 17mm (Fiat Bertone X1/9, Strada/Ritmo/UNO) - OE
www.midwest-bayless.com www.midwest-bayless.com

There was some talk here of an alternative wrench meant for an aircraft that can be used here. Do a search here for more details. Otherwise...perhaps someone here has a set of the special wrenches they could lend or rent to you......

Hope this helps...
 
It is true that a Russian aircraft cylinder head wrench can be used. I had one made for me by someone on eBay because I needed a 14mm version for my ARP hardware.
Also, I just went through the unfortunate head gasket replacement after only 4 months following a fresh build... Apparently, after assembly the SOHC requires a retourque after a single heat cycle, then again after some run in. I didn't do that initial heat cycle retourque, and consequently the head gasket failed after just a few months..😭
 
Lowtechprime said:
It is true that a Russian aircraft cylinder head wrench can be used. I had one made for me by someone on eBay because I needed a 14mm version for my ARP hardware.
Also, I just went through the unfortunate head gasket replacement after only 4 months following a fresh build... Apparently, after assembly the SOHC requires a retourque after a single heat cycle, then again after some run in. I didn't do that initial heat cycle retourque, and consequently the head gasket failed after just a few months..😭
Click to expand...
I think Lycoming is an American company... the cranked wrenches you can buy in 9/16, 5/8 and 3/4 are the ones you can use for retorquing the SOHC cylinder head... and they fit some model of Lycoming aero engine.

The 9/16 fits the 14mm ARP hardware, and with judicious use of a triangular file can be made to suit the 15mm head bolt type. the 5/8 wrench, again with judicious use of a triangular file will fit the 17mm head version, and the 3/4 is a snug fit onto the 19mm versions.

It reaches all the bolts, you just need to remove the engine top stay bar bracket to the cambox to access the rear trans end fastener... for the centre fasteners sometimes you need to remove the carburettor from the manifold (which is far easier then removing the manifold or the cambox)

SteveC
 
Lowtechprime said:
It is true that a Russian aircraft cylinder head wrench can be used. I had one made for me by someone on eBay because I needed a 14mm version for my ARP hardware.
Click to expand...
Not Russian, if they were they would be metric, not "imperial" sized.
~Where did this belief come from?


The cylinder base nut wrenches are for Lycoming or Continental piston aircraft engines of US of A origin.
These cylinder base nut wrenches are available from Aircraft Spruce:
www.aircraftspruce.com

Lycoming & Continental Cylinder Base Nut Wrenches | Aircraft Spruce

Lycoming & Continental Cylinder Base Nut Wrenches Made of top quality tool steel. 12 Point with 1/2
www.aircraftspruce.com www.aircraftspruce.com
More selection here:
www.aircraftspruce.com

Wrenches | Aircraft Spruce

Aircraft Spruce is a worldwide distributor of certified and homebuilt aircraft supplies.
www.aircraftspruce.com www.aircraftspruce.com


Bernice
 
Rupunzell said:
Not Russian, if they were they would be metric, not "imperial" sized.
~Where did this belief come from?


The cylinder base nut wrenches are for Lycoming or Continental piston aircraft engines of US of A origin.
These cylinder base nut wrenches are available from Aircraft Spruce:
www.aircraftspruce.com

Lycoming & Continental Cylinder Base Nut Wrenches | Aircraft Spruce

Lycoming & Continental Cylinder Base Nut Wrenches Made of top quality tool steel. 12 Point with 1/2
www.aircraftspruce.com www.aircraftspruce.com
More selection here:
www.aircraftspruce.com

Wrenches | Aircraft Spruce

Aircraft Spruce is a worldwide distributor of certified and homebuilt aircraft supplies.
www.aircraftspruce.com www.aircraftspruce.com


Bernice
Click to expand...
?? They are metric. I got a 14mm, 12 point cylinder head Russian wrench... Fits better than a sloppy 9/16ths and the bottom is tapered for the ARP 12 point nut...
s-l1600.jpg
 
Last edited:
Was an eBay seller named fishmouth500, listed as
Vedeneyev M14- 12 point CYLINDER BASE NUT WRENCH...
He makes them to order, so you have to wait a bit to get it...
 
Lowtechprime said:
Was an eBay seller named fishmouth500, listed as
Vedeneyev M14- 12 point CYLINDER BASE NUT WRENCH...
He makes them to order, so you have to wait a bit to get it...
Click to expand...
Industry standard cylinder base nut wrench with the box end cut off then socket welded on. The blue color change in the metal indicates the heat involved with that welding process which will alter the heat treatment of the modified socket and cylinder nut base wrench, not ideal.. but would work. Could be easily done by any local mech shop or not too difficult with a welder or by brazing..

Keep in mind:

14mm = 0.5511"
9/16 = 0.5625"

Difference of 0.0114"
Which is not excessive for wrenching.. You're not gonna apply 200+ ft/lb of torque on those 14mm APR twelve point nuts, and twelve point wrenching about doubles the wrenching surface area.

Another way is to get/use these hex to square socket drive adapters. 9/16" hex makes a 3/8" square drive, 3/4" hex makes a 1/2" square drive, low cost too.. and allows using common sockets with a cylinder base nut wrench.
www.harborfreight.com

Square Drive Socket Caps, 3 Piece

Amazing deals on this 3Pc Square Dr Socket Caps at Harbor Freight. Quality tools & low prices.
www.harborfreight.com www.harborfreight.com
As for wench sizes and tolerances (all things mech & tech are not made to the numeric "spec").. Chart from the Stahlwille catalog:

Stahlwille wrench size chart-2_sm.jpg


Stahlwille wrench size chart-1_sm.jpg


Bernice
 
Previously discussed from 2014:

Re-Torqueing The Head

There has been a lot of discussion lately of head gasket failure, and the proper torqueing technique. Having just replaced my head gasket, I will need to re-torque, so.... I figure a re-torque after my first run at temp, and then again at some future interval. I do not drive this car unless...
xwebforums.com

Another related from 2011:

Angle torque head bolt advice

I have new head bolts for the Uno turbo, but the long ones are shorter by the thickness of the washer. They also have heads with a washer-like base. There are three options that I'd like to run by those that would know (Bernice?) 1) Use no washer. While the bolt heads have a washer-like...
xwebforums.com

Reminder, "Torque isn't Tension".


Bernice
 
"The blue color change in the metal indicates the heat involved with that welding process which will alter the heat treatment of the modified socket and cylinder nut base wrench, not ideal.. but would work"


The wrenches from fishmouth500 are heat treated after manufacturing/welding to restore the relevant strength, then Cad plated..
 
Rupunzell said:
Industry standard cylinder base nut wrench with the box end cut off then socket welded on. The blue color change in the metal indicates the heat involved with that welding process which will alter the heat treatment of the modified socket and cylinder nut base wrench, not ideal.. but would work. Could be easily done by any local mech shop or not too difficult with a welder or by brazing..

Keep in mind:

14mm = 0.5511"
9/16 = 0.5625"

Difference of 0.0114"
Which is not excessive for wrenching.. You're not gonna apply 200+ ft/lb of torque on those 14mm APR twelve point nuts, and twelve point wrenching about doubles the wrenching surface area.

Another way is to get/use these hex to square socket drive adapters. 9/16" hex makes a 3/8" square drive, 3/4" hex makes a 1/2" square drive, low cost too.. and allows using common sockets with a cylinder base nut wrench.
www.harborfreight.com

Square Drive Socket Caps, 3 Piece

Amazing deals on this 3Pc Square Dr Socket Caps at Harbor Freight. Quality tools & low prices.
www.harborfreight.com www.harborfreight.com
As for wench sizes and tolerances (all things mech & tech are not made to the numeric "spec").. Chart from the Stahlwille catalog:



Bernice
Click to expand...
Did you just recommend a tool from Harbor Freight?!? :eek: What is the world coming too...
 
Steve Thomas said:
Wrong is wrong,. Please all, do not use imperial tools on metric fasteners. If you own an X, you need metric tools.
Click to expand...
I disagree for the head torque tool.

The 9/16 lycoming aero engine cranked wrench is a good fit to the ARP 14mm 12 points, I've used it many times.... it's available, well priced, and gets around the cambox well.... a 14mm wrench is never exactly 14mm anyway, there is a "class" fit, and the 14.25mm or the 9/16 is barely out of class. Maybe if we were doing the bolts to 200ft/lbs it would be an issue, but at the moderate torque settings we need it for, it's not going to fail or slip.

If you have a set of the later SOHC head replacement head bolts, then as I said, a judicious use of a triangular file on a 9/16 aero engine wrench will give a nice snug fit on a 15mm bolt head without a lot of effort, again it's well priced, available and fits the engine.

SteveC
 
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