Hi Guys,
Still trying to get a fan belt that fits on my XK120. I was very close today! Tried to install a Gates TR24379 (21/32" x 38-1/2"). My poor baby has been undriven for many, many weeks…
I believe that I am approx within 1/4". Need a belt 1/4" wider in diameter.
Can anyone recommend one that is 38-3/4"?
Thanks!
Bob
I have a lengthy document on xk fan belts…to send to you via email…but I don’;t know how to do that in this new forum format…Nick
Bob,
I believe I still have a new, original Ferodo V144 belt in its box. I could check if you want to use an “old stock” belt. I personally drive my XK140 with a Ferodo V917 fan belt and no problems so far (though I always carry a spare one of course). Let me know via PM.
Regards,
Bob K.
Bob K’s XK140 belt is too narrow for a 120.
They don’t make belts in 1/4" length increments.
Something else must be wrong if a 5L380 doesn’t work.
That’s what I use.
Here is some info on belt sizes.
I think this link will work, but if it just takes you to the McMaster home page, select power transmission and then belts.
Can you measure your water pump and generator pulley diameters?
Or post pictures and maybe we can figure out what’s wrong.
Rob,
In my message to Bob, I referred to the Ferodo V144 belt which is a 3/4" belt equal to Jaguar C.5056, spot on for the 1953 XK 120. The photo of my own XK140 was just to show that it is possible to use a 40 year old fan belt as long as it has been properly stored.
Regards,
Bob K.
Nick - can you please send me your document on XK Fan Belts.
You have my email, but its:- rogerpayne@bigblue.net.au
Don’t like hijacking threads, and this one is titled '53 XK120 DHC Fan Belt and my immediate first interest is XK140 belts, but am also interested in XK120 (totally different), and my recent paper on E-Type Tool-Kits includes mention/pictures of spare-fan-belts supplied with new E-types as part of their “Tool-Kit”.
Just as a starter - I maintain factory original XK140 Fan-Belt was a DUNLOP D333 and I have a New-Old-Stock that I obtained with a near-complete XK140 MINOR REPLACEMENT OUTFIT kit.
Roger
Rob,
My 38 1/2" belt is ribbed and I just cant get it pulled enough to get over the 3 pulleys. I have tried to initially put over the crank and the water pump, then try and pull over the generator pulley. Also tried where the last pulley to do is the crank… It’s close, just cant seem to get it over.
I have the generator all the way lifted up so its touching the engine. I have not removed the rear bolt to try and angle it in.
What is the correct way to install the belt? Maybe being ribbed it the issue? Maybe its too deep of a belt, need a 38 1/2" thats less deep? I think that would work…
Thanks,
Bob
I use the B36 belt on my '54.
B36 generic number from NAPA or anywhere.
There were at least two sizes of generator pulley used in the '46-54 period.
C.1076 and C.2579, these numbers are stamped between the vanes.
I wonder if you tried a 39" size?
5L390 belt intended for light duty is 39" circumference, 21/32" width and 12/32" depth.
B36 belt intended for medium to heavier duty such as air compressors is 39" circumference, 21/32" width and 13/32" depth.
BX36 cogged belt intended for smaller pulleys is 39" circumference, 21/32" width and 13/32" depth.
Hi Rob,
Yes, tried the 39" and could not get it to tighten up. Ran out of slack in the adjuster.
I am going to retry the Gates TR24379 using a belt install tool that I just ordered. Connects to the crank pulley and you turn the crank using a ratchet until it slides over the pulley lip and into position. I am thinking that I just dont have a good enough grip working to get it over the generator pulley. The radiator and holding rod don’t let me get a good angle, plus I could be weak…
Thanks, Bob
Further to this topic…(info lifted from I think a “Bob” web site…apology for not having proper credit of source) Early Jaguar XK 120s used a 13/16” (20.6 mm) wide 32° V-angle belt type. Around 1952 this belt type changed to a ¾” (19 mm) version still with a 32° V-angle.Important TO FIT IS THE V ANGLE,as we will see: Belts with the original widths and 32° V-angle for the early 120s are no longer manufactured but belts with a 36° or greater V-angle are, but this can change how the belt rides in the pulleys, thus the optimal length. “Notched” or flat can be used. Now…for pulleys: note that the Jaguar Mk IV and Mark VII used a similar pulley, part number C1076, however with a 3¾” or 95 mm diameter. These larger pulleys may have been used as a replacement on XK 120 engines and will affect the required length of the fan belt. So check the part number of the pulley which is stamped in the casting between the vanes! engines from W1001 up to W5464 (July 1952) with crankshaft pulley C2469 (4¼“ or 108 mm outer diameter) used pulley C2246 (6“ or 152 mm outer diameter) on the (round hub) water pump with the cast 5 blade fan and a cast iron pulley C2579 on the C45PVS generator (3½ ” or 89 mm outer diameter). The fan belt was coded C2240.
The later XK 120s from engine number W5465 (July 1952 till end of production) still had the same crankshaft and generator pulley but the water-pump pulley changed: to a much smaller pulley (102 mm or 4” outer diameter) now integrated with the water pump hub and the combination was coded C5054. There was a 4 bolt flange for the new 6 blade fabricated aluminium fan. The new shorter fan belt was coded C5056. Now,the B36 belt (or crosses to it by dimension) may fit because, although with a width of 21/31” (17 mm), it has the correct outside length of 39” or 990 mm. It will run deeper in the 32° V-groove which again is somewhat compensated by the wider V-angle of 36°. OR Gates TR24379 might come close with an outside length of 38½” (980 mm) which is only 14 mm too short, For the XK 140: a 40° V-angle belt instead of the former 32° V-angle, also a much narrower type of about 13/32m 10.3 mm versus the wider 19 to 20 mm of the XK 120. The crankshaft pulley also changed (now C7275) with a 5” or 127 mm OD, the water-pump pulley was new (C7644) with a 5¼” or 134 mm OD, as was the dynamo pulley (C7427) with a 3½” or 90 mm outer diameter. All XK 140s had the same fan belt which was coded C7898. The same dimension belt, was continued for the XK 150 until 1959 when a wider belt type was introduced with a width of 0.526” (13.4 mm) and 40° angle which changed still later to ½” (12.7 mm) 40° belt. So replacement depends on V angles, and which pulleys (crank, waterpump, generator) are in place. No doubt with the years gone by, what fits one application may not fit the next similar…but different…engine. Once you know what parts you have, the trial and error process may be shortened. Again, thank you to the “sources”. Nick
Here is a list of belts I tried and the results:
Gates TR24400 40 5/8" too long
Mintex TK339 40" too tight
Gates B36 39" fits oK This is what works for me.
Gates TR24379 38 1/2" Too tight
Gates 5L380 38" Too tight
CarlH
1951 XK120 FHC with later model water pump (small pulley)
