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TR2/3/3A belt size for TR3a?

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2billydavies

2billydavies

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hi everyone...
don't suppose anyone knows the dimensions on the V-shaped serpentine belt for a 1958 TR3a off-hand, would you? Mine pretty much slipped, melted, and smoked all the way home last night. Forgot to bring it with me to work so that I can stop by AutoZone on the way home to snag one. Was hoping to save a trip back out.

thanks a ton!
Billy
 
Hello Billy

This is what I have on my TR3 motor. Is fitted with an altenator so the belt may be a little short.

On the belt it has TR24379 Green Stripe 11 Belt 17A0960

David
Fan belt.jpg
 
Thanks guy. Where did you purchase your belts at? I was hoping to buy it locally but nobody has the belt that was on my car. I just didn't want to wait for Moss w/ the holiday tomorrow and all. Thanks!
 
Got mine at a local store that caters to larger trucks and buses. Was directed there by a guy at Auto-zone.

You might try OReillys.

David
 
20mm x 900mm is a common size for TR belts (for an all-stock setup with generator and the "wide-belt" pulleys). I went out to the garage to check my stock:

Cogged-type from Roadster Factory was "Bando" brand, #9375, 20mm x 905mm.
Another cogged one (with what looks like a Moss Motors sticker on it) was "Flennor" brand (german) #2380, 20mm x 900mm.

Putting the longer 905mm belt on is easier than the 900mm one.
 
This week, I had to replace the fan belt on my 1960 TR3A. The belt that failed was marked "Gates 17A0960". According to Gates, it had a 17mm top width and 960mm outer circumference and cross-references to a Gates 24379. I replaced the failed belt with a Napa 25-24379 (made by Gates) that I'd been carrying for a few years. It wasn't easy to install, but I got it on with some effort.

Today I bought a new NAPA 25-24379 so that I'd have a spare. I was surprised to find that it is different than the old 25-24379.

The old NAPA 25-24379 was marked as 3/4" (19mm) x 38 1/2" (980mm). The new NAPA 25-24379 is marked as 21/32" (17mm) x 38 1/2" (978mm). Both are made by Gates. That's not a huge difference (less than 1/10" in both width and length) but I didn't want to buy a belt that might be even harder to install.

I called Gates. Their customer support line recommended Gates TR28386 (20mm x 980mm) for a TR3A. Many TR owners moved to 24379 because, being narrower, it was easier to fit than the 28386.

I asked Gates if a 17,18, or 19mm x 980 mm belt was available since that might be easier to install. They don't offer 18 or 19mm widths. The closest sizes that they have in 17mm, apart from the new 24379 are 17x961 mm (shorter than the 24379) or 17x1017mm (too long).

I don't know if being 2mm shorter will make the new 24379 harder to fit or not. However, it (along with the 28386) are the best choices offered by Gates/Napa.
 
By hard to install I assume you mean getting it through the space between the pulley and the drag link? In case you do not know, turning the wheels full left or full right should open up that gap a bit, possibly enough.

One can also shim the motor mounts (or perhaps replace them) to gain some clearance. I added shims on my TR4 since R&P steering means the gap does not change as the wheels are turned.
 
In 2008 I replaced my belt with the NAPA NBH 25-28386. This is the recommended belt for a 1966 TR4A by both Gates and NAPA. I don't recall issues getting it around the fan or fan hub (I may have jacked the motor) but, it was very tight to get over the pulleys. This was with the generator adjustment fully slack. Once installed, I only had to move the generator 1/4"-1/2" to tension the belt. It seemed to me I could have used another 1" in belt length. Specs on the NBH 25-28386[FONT=&quot][/FONT] are 39.17" x 0.875" (995mm x 22mm).

Bob
 
Don't know as the motor is still on the floor not in the frame. As far as I know that is the way it came out but I have added the yellow fan.
Is there something I should know about that fan?

David
 
DavidApp said:
...I have added the yellow fan. Is there something I should know about that fan?
Click to expand...

Clearance (gap between the fan and the radiator) is sometimes an issue with that fan. On my TR4 (which is admittedly different from a 3a) I had to install it backwards and use a spacer I cut from a plastic cutting board to get it in a good spot - yet I have seen some that required no such measures.

Just something to keep in mind once the engine is in and you offer up the radiator.
 
Thanks for the heads up on that. Have a old style radiator with the crank hole that I had pressure tested. Don't want to damage that.

David
 
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