Volvo Penta 3.0 Sx | Outdrive nut size?

[baker556]

Hi fellow boaters,

Looking to take the outdrive off very soon before taking her out this season, just wanted to check, the six nuts on the outdrive what size are these so that I can source a replacement.

Many thanks!

 

[baker556]

These:

Lock Nut for Volvo Penta SX & DPS & OMC Cobra, Replaces 3853329 - Nuts, Screws, Springs, Washers - Parts for Volvo Penta Sterndrive - Volvo Penta Engines & Sterndrives

<p><span style="font-size: medium;">Lock Nut for Volvo Penta SX & DPS & OMC Cobra Sterndrives</span></p> <p><span style="font-size: medium;">Used to fix upper gear housing to bell housing</span></p> <p><span style="font-size: medium;">Replaces V

repowermarine.com

But without paying the extortionate fees.

 

[dubs283]

7/16 - 20 nylock shouldered nut

you can probably get away with stainless but the oem nuts are chrome plated brass

 

[baker556]

Hi Dubs283.

Thanks for this information.

I guess this justifies the cost from an online retailer then.

Is there a reason for using the brass type? To stop the nut from getting loose? Although the outdrive is submerged it's not like it gets overly hot.

Would stainless nyloc be up to the job?

 

[Horigan]

Stainless is fine. Be sure to put sealant on the studs per the manual.

 

[baker556]

This is the only one I could find, quite expensive for 10 (6 req) around £16.00 delivered.

A4 STAINLESS STEEL FLANGED & SERRATED NYLON INSERT NYLOC NUT - NUTS / FLANGE | eBay

A4 Stainless Steel Serrated Flanged Nyloc Nuts. Serrated Base. A4 Marine Grade Stainless Steel. Nylon Insert.

www.ebay.co.uk

This is for the M12 flange with nyloc stainless steel grade A4 for marine use.

Chris

 

[dypcdiver]

The studs are 20 TPI (threads per Inch) not Metric. and the nuts require a 5/8"AF Spanner.

 

[baker556]

thanks diver.

5/8 is the spanner size, that is a 16mm socket and the above-linked nut is M12 16mm - should that not work?

Just checked with local volvo they want £41 for these same nuts.

I need to find the right ones!

 

[baker556]

Any further info guys?

Thanks

 

[dypcdiver]

No, that will not work. Studs ie, the ones the nuts go on, are not metric.

 

[baker556]

Is the pitch not the same dypcdiver?

 

[dypcdiver]

So what you are suggesting is that you put put a 12mm nut on a 7/16 UNF stud, because it is cheaper.!!!!

 

[baker556]

Hey Dypcdiver you are right - I'm not fully clued up in the area of metric Vs imperial.

I thought if the pitch was the same it's possible this would work, obviously not.

I've found somewhere that stocks 7/16 - 20 but without the serrated part, would a standard washer suffice?

7/16-20 UNF Imperial Hexagon Nylon Locking Nuts - A4 Stainless Steel: Accu.co.uk: Nuts

Buy 7/16-20 UNF Imperial Hexagon Nylon Locking Nuts - Marine Stainless Steel (A4) from Accu's Nuts range. Manufactured by AccuScrews. In stock with express worldwide delivery available.

www.accu.co.uk

7/16 inch Flat Washers (ANSI B18.22.1) - A4 Stainless Steel: Accu.co.uk: Washers & Spacers

Buy 7/16 inch Flat Washers (ASME B18.21.1) - Marine Stainless Steel (A4) from Accu's Washers & Spacers range. Manufactured by AccuScrews. In stock with express worldwide delivery available.

www.accu.co.uk

Thanks,
Chris

 

[Horigan]

I think a lock nut with just the nylon insert is sufficient. I seen that on other OEM nuts.

 

[baker556]

Thanks for your help guys - placed the order now!