Top trunion threads

Discuss mechanical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
Post Reply
jaguar68
Minor Fan
Posts: 336
Joined: Mon May 18, 2009 9:10 pm
MMOC Member: No

Top trunion threads

Post by jaguar68 »

Hi Guys,

Does anyone know if the upper trunion pins threads change at any time? The new nuts I've bought for my '56 Series II trunions don't fit, leading me to believe that they may have changed at some point.

Also the grease nipple threads are 5/16" BSF as opposed to to 5/16" UNF.

Cheers

John
bmcecosse
Minor Maniac
Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
Location: ML9
MMOC Member: No

Re: Top trunion threads

Post by bmcecosse »

Upper trunnion pins threads ?? Not getting you there........ Is it the pin that fits into the damper arm - and the top trunnion mounts on with largish polyurethane (I hope!) bushes ? What thread nuts did you get ?
ImageImage
Image
mike.perry
Series MM Registrar
Posts: 10183
Joined: Sun Jul 24, 2005 11:39 pm
Location: Reading
MMOC Member: No

Re: Top trunion threads

Post by mike.perry »

There was no change in the trunnion threads except that the left side of the car are left hand threads as is the stub axle and bolt
[sig]3580[/sig]
bmcecosse
Minor Maniac
Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
Location: ML9
MMOC Member: No

Re: Top trunion threads

Post by bmcecosse »

Ehhh? It's the PINS being discussed here - not the actual trunnion swivel threads.........
ImageImage
Image
les
Minor Maniac
Posts: 9194
Joined: Tue Feb 12, 2002 12:00 am
Location: kent
MMOC Member: Yes

Re: Top trunion threads

Post by les »

Yes the pins did change threads, although it may be because some are pattern parts. the finer thread I believe is bsf and the other unc but you need to check this info.

jaguar68
Minor Fan
Posts: 336
Joined: Mon May 18, 2009 9:10 pm
MMOC Member: No

Re: Top trunion threads

Post by jaguar68 »

Ok, the nuts for the Upper Pivot Pin, part number 79 on the Morris K2 diagram, Bull Motif Part No SUS 143, are SUS 147, Nut for Top Fulcrum Pin (Plain) and SUS 148, Castle Nut (Top Trunion Pin). What the thread forms are is anyones guess, as they are not specified on the website. Ok, they are not very expensive, but it's not much help when they don't fit.

The Trunion Pins are the original ones removed from the car, so are certainly not pattern parts. If I'd have known that the threads were different, I could have ordered them when I ordered the 5/16" BSF grease nipples, which again are not the standard one sold on the websites.

Regards

John
aupickup
Minor Maniac
Posts: 6004
Joined: Tue Jul 20, 2004 11:41 pm
Location: lanark
MMOC Member: No

Re: Top trunion threads

Post by aupickup »

both types are genuine ones
Post Reply