Thrust washer explained

[CodeRed225]

I searched a bunch on here for the correct thrust washer setup and just got a bunch of part numbers for combinations of prop, thrust washer setup. I am wondering what should the fitment look like. I just bought a prop that I want to try but the prop doesn't seat against the thrust washer the same as my other one. Should the prop housing or the hub seat against the thrust washer? It seams to me that the prop should bottom against the thrust washer (my current prop does just that). The new one (29 srx) does not.
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This doesn't seam right. All of the force or thrust would have to travel through the rubber insert to the hub then to the thrust washer, shaft, etc. I am also wondering should the hub touch the thrust washer also? Or just the prop. I hope I have explained my question good enough. I just want to know the way the whole setup is supposed to work then I'll be able to recognize a right or wrong situation in the future. I don't want to just rely on someone saying "here's the thrust washer you should run, that's what the book says, good luck".

[dompie99]

I have a couple of props and it seems that every one has it,s own.

I have two Choppers one mazco and the thrust washer fit snugly, on the other one, there is a little gap not as much as yours but there is one.

That was my 2cents

[97mirage]

Call DAH Propellers and tell them what prop and shaft/gearcase you're running. They will know what you need. I needed hardware for running a 29 SRX and they knew exactly what was required. Google their website for contact numbers. Good luck.

[CodeRed225]

I drove to Dah on sat. He looked at it and said it was right. It just seams very different from my chopper prop setup. I'm trying to understand the purpose and function. I ran it tonight and when I installed it the prop did bottom on the thrust washer. Lot of stress on the rubber insert though. I would like know the correct setup by looking at it, not according to part numbers.

[rock]

The thrust washer should contact both the hub and the prop. This takes all the load off the rubber.

Rock

[panther150]

One of the guys at DAH designed the SRX when he worked at OMC , they should have given you the correct info. Post pic of your thrust washer with the part number. I had to run a specific washer for mine setup as well instead of the standard merc 13 spline thrust washer. it sets the prop back further and fits very tight from your pic its definetly fifferent than yours. I can post a pick and part number this weekend when I am up north if you like.

Steve

[panther150]

I think its OMC part # 126870 witch is Sierra 18-4223. you will se how it different and sets the prop back further on the shaft. Mos importantly , it fits tightly in the rear of the prop removing all movement and removing stress from the rubber bushing.

[Sonik]

John and Jeff @ DAH should know..and if they say its good, it should be good. I run a 27 and 29 SRX on my boat as well. When I get home from work, I'll pull my props out and get a shot of the thrush washer I'm using (which does sit flush and have correct OD) for you if the above part #'s don't shake out.

[panther150]

the thrust washer in his pic above looks like the standard Merc washer.

[CodeRed225]

Thanks for the replies everyone. The prop/washer setup in the pic is exactly what I brought to Dah. John looked at it, looked at the part number and he said it was right. Sorry I don't have the part number right now, but does it really matter. He said that gap was fine. And like I said it bottomed out when I torqued the prop nut down. Doesn't seam right though. My chopper prop bottoms the prop before the hub, but the srx bottoms the hub before the prop. One should be wrong, or least better than the other.

[Magcat 62]

I have exactly same set up my chopper replacement srx washer hits hub first brought prop and washer to shop was told prop will move forward on rubber hub and close slight gap i still dont feel comfortable and havent ran it yet tryin on 20 shadow 220 merc ithink it should hit stainless prop tube not inner spline sleeve! Im clue less

[transomstand]

John looked at it, looked at the part number and he said it was right. And like I said it bottomed out when I torqued the prop nut down.

This is the key, as long as it's flush with no gap when installed then it's fine. You can change to a washer with a more shallow step but it's not necessary. Rubber hub installation in props is about as precise as brain surgery with a sledgehammer and there are different lengths that can be interchanged, so "vertical" discrepancies are not unheard of.

You asked the purpose of the thrust washer. It provides a firm surface for the splined sleeve so the correct torque can be applied to the prop nut, and keeps the prop centered on the shaft (because the rubber hub can do neither). That's exactly what it's doing in this case.

[CodeRed225]

The part number of my thrust washer is 333592.325046

When I took the prop off, I noticed the gap between the prop and washer was back. Also I noticed the washer behind the prop nut had a cup to it.
325047

I don't like this. I realize under load it probably bottoms back out against the thrust washer, but that means there is movement. I don't like it.

Should I have the thrust washer turned down so the prop installs tight?

[panther150]

Thats not a bad idea if you have access to a lathe or know someone. The above statement is 100 percent correct though I have run many props just making sure the nut was tight before every run as we should anyway. It is a nicer setup when it fits over the washer at the back though

[transomstand]

The common washer for the SRX is 321173. That should have a more shallow step.