torquing carb to manifold

Engine troubles? Try here.
Post Reply
2013cossj
United States of America
Posts: 3
Joined: Thu Sep 22, 2022 1:25 pm

torquing carb to manifold

Post by 2013cossj »

Is there a need to semi tighten all 4 nuts, then torque down further in a certain pattern? Are the unique pinz washers required?
Thanks in advance.
User avatar
rmel
United States of America
Posts: 1394
Joined: Sun Sep 25, 2011 12:19 pm
Location: Woodside, CA
Contact:

Re: torquing carb to manifold

Post by rmel »

The serrated (or ribbed) lock washers are the best to use as they
lock well and without marring the surfaces as a split lock can do.
But in a pinch a split lock washer can be used.

I snug these nuts up with a box wrench going all around tightening
gradually as the gasket is very thick and compresses -- so don't over
tighten. Go back in a few months after several temperature cycles
and re-tighten if necessary. You just don't want a vacuum leak so
no need to be super tight.

In any case it's too tight to get a socket on several of the nuts esp.
with the tin on the front carb so torquing is not practical.
Puller: 71' 710K 2.7L EFI aka Mozo
Follower: Sankey MK 3, 3/4 Tonne
Rescue Pinz: 73' 712MK

Driver: Ron // KO0Q
Stumbler
United States of America
Posts: 19
Joined: Wed Jul 28, 2021 1:42 pm

Re: torquing carb to manifold

Post by Stumbler »

Although everything you read says no sealants or locking stuff is necessary on the carb or throttle body, I found (the hard way) that those bolts have a tendancy to loosen and then your system leaks right between the throttle body and the carb, which makes it run rough and stumble. Then it becomes a couple hour long ordeal to remove everything, tighten the bolts to the correct torque, and put everything back.

After the second time they came loose I used a little blue Loctite on them and torqued exactly to spec and my carbs have never come loose again in the last 5 years.
User avatar
Hotzenplotz
Austria
Posts: 371
Joined: Wed Jan 18, 2012 9:07 am
Location: Vienna, Austria

Re: torquing carb to manifold

Post by Hotzenplotz »

I use nuts from a tuning shop in Germany.
They offer M8 nuts for 10 mm spanners.
Image
https://www.universalauspuff.de/zubehoe ... 2154g.html

This allows me to torque the carbs to 20 Nm
Cheers
Albert
========================
My Pinz has NEVER been with any army
User avatar
rmel
United States of America
Posts: 1394
Joined: Sun Sep 25, 2011 12:19 pm
Location: Woodside, CA
Contact:

Re: torquing carb to manifold

Post by rmel »

For the record, the lock washers are "Schnorr" serrated. They lock well and are specifically designed to lock in the presence of vibration.
You can source them from Bell Metric (and other outlets). https://belmetric.com/steel-s-series-up ... rr-washer/

I'd recommend them over split locks or flat washers.
Puller: 71' 710K 2.7L EFI aka Mozo
Follower: Sankey MK 3, 3/4 Tonne
Rescue Pinz: 73' 712MK

Driver: Ron // KO0Q
Post Reply