I used this www.partzilla.com/product/yamaha/2HR-24500-02-00? petcock on my 1976 DT250C they range in price from $22-$30 from several different dealers or Amazon, it is an oem Yamaha part and was a complete brand new bolt on part except the brass fuel tube was a little longer I measured the original brass tube on the old petcock and cut the new one down with a tubing cutter. I would bet money it is the same for the 1975 dt175 as my DT250C you can verify this on the partzilla website. Yamaha used the same petcock for many applications.

I bought new mounting screws and mounting screw gaskets and installed a new fuel filter while I was at it. It has a different appearance but functions exactly like the original, something to keep in mind if oem appearance matters to you more than functionality. There are different part numbers that have the exact same petcock with the differences being the orientation of the fuel outlet at 6 o’clock, 3 o’clock or 9 o’clock, some also have different diameter outlets. The part number above worked great for me, there is a thread on here somewhere detailing the differences.

Also a side note I use to buy all the bits and pieces to rebuild the old petcocks and it is a very straightforward job but for some reason I usually had about a 60% success rate on rebuilding over 10 of them, I just chalked it up to worn out parts, maybe it was my skills or lack thereof? Once I found the thread on here detailing the part numbers and differences and tried the brand new Yamaha petcocks I haven’t looked back on trying to rebuild the 40-50 year old parts.

For the price they want for it, how can you go wrong? Drain the tank, slap on the new one, and then rebuild the old one to your heart's content!

www.partzilla.com/product/yamaha/498-245...2d32988080160d0a249e

This is the one listed for my model. I need to order a bunch of bulbs for the gauges since 6v bulbs don't exist in stores anymore apparently, so I was going to just order the repair-parts and see if I get lucky. It's not leaky, so maybe the valve is just stuck/dead.

I was going to hold off on buying the actual replacement petcock. If you have the same one cheaper than that (70$), I might take you up on it just incase.

I will say if you go by the part number for the alternative oem petcock that will function but physically look different you can’t go wrong at $22.00 from partzilla for a Yamaha oem part, I think that alternative oem part number originally fits a 4 wheeler? I have seen Chinese knock offs of that petcock in the $7.00 range on eBay, me personally I prefer the quality of oem on most items, I would definitely get new gaskets for the screws and if your old mounting screws are in poor shape I would get new screws as well, I am pretty sure you will spend more than that on trying to rebuild your old petcock, plus having to cross your fingers and hope the rebuilt one works, when I replaced mine I only had about a 1/2 gallon of gas in the bike, I leaned it onto the right side and removed the petcock, didn’t even have to remove the fuel tank, although if you do remove the fuel tank you might be surprised at some of the junk that comes out sometimes, I was done in less than five minutes, new petcock, screws, screw gaskets, fuel line, fuel filter.

You mentioned this one:
www.ebay.com/i/222597000404?chn=ps&norov...fEAQYASABEgJ-uvD_BwE

Will it not work? I would not go buying the $70 unit. You asked on a scale of 1 to 10 where does cleaning and rebuilding a petcock lie? I'd seriously say about a 1.25. You seem worried about the joint between the petcock and the tank, and you may encounter some rust there, but when the bolts have been stuck on some of the ones I have rebuilt (Have rebuilt about ten, now), I have used an impact driver TENDERLY so as not to dent the bottom of the tank, and they have always released rather easily. Put a little penetrating oil on them, and tap them with a small hammer, and that may help, too. But for obvious reasons, don't use heat on these bolts! You can do this really easily.

I would not use that 9.49 ebay one as it looks like what you have...

Several Yamaha ones that work fine for less can be found here:

yamaha-enduros.com/index.php/forums/perf...tcocks-for-our-bikes

My point about the eBay one initially was in regards to mark mentioning that it was probably a cheapo one and that might be where it came from. I had no intention of buying that thing!

I think mine is an actual one since it turns out it looks like it matches the Partzilla OEM one and that rotated orientation isn't wrong.

We got some hilariously stupid rain/snow/wind/wtf is happening weather today so I didn't mess with it or open it up.

I'm aware of either the one listed for my DT175B (70$), or the ATV one (its around 22$ now) that was mentioned here years ago. If I can get away with just swapping the valves and such for less money, I will hold off on swapping the whole unit out, especially if it's just a dead valve.

The tank is already off the bike because of my voltage regulator/blinker adventures, so I can do whatever and just want to avoid buying extra stuff.

What I am going to do is order the mounting stuff for a new one, the valve and such for an attempted repair, and then hold off on buying a new petcock until I see if this goes OK.

Worst case scenario, i have some extra screws and a gasket.

Even if I buy the 70$ one, I miss that free shipping. Boooo, lol.

You're right.... My 75 and 76 DT175's must both have had the petcocks changed...

I looked at the owner's manual and with the lever parallel to the ground, it's "off".

With the long end of the lever pointing down, it's "on".

With the long end of the lever pointing up, it's "reserve".

I don't remember that style petcock... learn... or re-learned... something new today.

on the bright side, this means it's at least not a cheapo knockoff most likely.

Are they likely to rust and get all crapped up? I find it kind of odd the screws are really worn but the petcock is not. If the hail outside stops in a bit I might go out and pop it open and see how bad the valve is. Maybe it's just stuck and can be loosened up.

Though, the valve is almost as much as buying that other OEM one from 4 wheelers, so it's a bit of a wash and almost seems better to just buy a new one!

Photos of the one I got from Babbitts recently for my 73 DT3 when I sealed and had the tank repainted. The one that came on the bike had a different pattern and also fed the fuel from the back instead of this one that feeds from the bottom.