Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Torque for king pin bolt

I am fitting brake reaction stays to my 2019 Plus-4.
Does anyone know if the appropriate torque setting for the top king pin bolt which attaches the top of the stay. The other end of the stay attaches to the chassis at roughly a 45 degree angle.
Is there any other advice when fitting these stays?
Many thanks
RayS

Ray, I have written an in depth fitting description on here so search sewin and you should get to find my posts several others, daveW and richardV6 also.

Now this is not as strait forward as you may think and can in fact be very dangerous so if you are not that mechanically minded beware, you are dealing with a spring under pressure.

There is a way to do this safely so please make sure you arm yourself with the relevant information. There are three main aspects

:

Safety when working with suspension units under pressure.

techniques which allow you to do this easily and safely

little things that may cause problems for you or the car if not observed



Now to answer your initial question.... torque setting. Well Morgan works won't give you one and truthfully I don't think there is one! But bear in mind you are dealing with a hollow bolt and they can shear so the old adage of tight is tight and too tight is bust applies here. I have seen torque settings bandied about but I think they have evolved from the ether and an individuals opinion. There are other things that you need to know about these oiler bolt installations too. If you struggle to find the info you are welcome to PM me and I'll happily go through it in detail with you. But again don't start until you know what is what!

The most important tip, is to apply light pressure under the kingpin. This will prevent the top shifting slightly as the oiler bolt comes out, and will help locating the bolt going back in. The bolt is a fine thread, and can be difficult to restart if the kingpin moves fractionally. I've also seen an oiler bolt shear.

At the chassis end get the reaction bar as far inboard as possible. Filing a corner off the inboard edge of the bar gets it further in. This is because clearance to the tyre can be tight.

Something important to note. Considering the front forces present in a sports car, no degree of torque could stop the kingpins from moving without the following design feature.

The top of the kingpin fits into a recessed indent (more accurately a "detente" in French) which is cut into the upper support plate welded to the cross frame. When securely fit into this slot, the kingpin cannot move with sufficient force. One merely torques to the amount to the amount that reflects the quality of a well-chosen top bolt. https://www.gomog.com/allmorgan/bolttorque.pdf Sadly the MMC did not give out such the grade information for bolt or kingpin, in the day. I use either 8 or 5 bolts and hard-chromed C1045 or C4140 bar stock (the "C" stands for carbon steel) . These cost no more than anything the MMC has ever used.

Below is bad (very old) images of the slot from a snackered crossframe, and an example of what can happen with ungraded sadness.

L

Ray as the kingpin top bolt is hollow to allow grease nipple there isn't a torque setting published. Tight with an open ended spanner and a nudge for good measure is often mentioned so its not critical. Fitting brake reaction bars gives you the opportunity to ensure grease nipple faces forward for easiest grease nipple attachment. Loosening bottom nut a tad if needed will allow kingpin itself to rotate so this is achieved when top bolt is adequately tightened.

The modest age of your car means it will be fitted with adjustable camber plates and round nosed upper end kingpins to allow them to swivel in and out very slightly at the bottom to facilitate adjustment. Camber shouldn't need adjustment when fitting brake reaction bars (BRB) and I mention only because there are a complimentary pair of washers, upper convex and lower concave, that fit together immediately under the kingpin bolt to take account of the variable angle it can sit at. These need to be thoroughly cleaned and regreased and of course sit above your new brake reaction bar as shown below.



In a perfect world the kingpin bolt should just engage with the kingpin threads after fitting BRB's but must be started by hand before tightening with a spanner to avoid crossed threads! In practice I've found this is occasionally not easy one side or the other. A trick I discovered when doing a full kingpin replacement can be read in this post for cars with adjustable camber.

Thanks guys for all your inputs and advice.
I also watched the Utube from Caveman which clarified things in my mind..
Cain at Wolf Performance supplied the stays and also two new flanged top bolts. My only query now is whether they will be the correct thread as I am not fitting new king pins.
I will let you know how I get on!
RayS

Three possibilities Ray.

(1) Cain guessed you had hard chrome kingpins already fitted as supplied by him from Mulfab with metric internal thread matching his flanged bolts.
(2) He is now supplying flanged bolts to match the OE kingpins with ½" BSF (I think) internal threads.
(3) They won't fit although comparison with original will show obvious difference - in which case you will need to re-use originals.

BTW just noticed your location not so far from me and often visit Woolpit for cheapest fuel. If you need any help just PM.

Ray you are welcome also to come to FolkMog events see folkmog.net . I am the centre sec.

We also hold none MSCC runs out as the Great Escape Gang every Wed
I'm sure we will drive to Suffolk pub next wed. Pm me your email if you are interested

Ray, I am one of the Great Escapers with a GDI Plus4 fitted with brake reaction bars. A very worthwhile addition. A Panhard rod should be next on your list.

Thanks to RichardV6, John V6 & Themorganeer for your advice & comments.. John I have sent a PM.
Assuming I have successfully completed fitting the brake reaction stays I hope to come to the Suffolk meet of the Great Escapers. I have joined Folkmog too.
regards
RayS