Reference: Ford V8 fan belts: off the shelf replacement

[Hanno Spoelstra]

Then I had a closer look at the old belts. As you can see they sit low down in the pulley, a tell-tale sign of wear. Luckily, the belt was not bottoming out:
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Fitted the same make and size of belt, but unworn (bottom one in LH picture). Worn belt on top of and unworn one - note the obvious difference in length!
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Approximate dimensions (mm) of BTR 51050 V-belt: worn | unworn
Internal length (Li): 1373 | 1355
Upper belt width: 16 | 17
Lower belt width: 8.5| 9.5
So, the width of the belt decreased by 1 mm, and the length increased by 18 mm - they do strech!

Generator bracket is now fitted on the adjustment bolt properly (compare with above), but still at the end of its adjusting range:
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New B52 belts are on order, should be available over the counter tomorrow. While the B52 belts are 35 mm shorter, it will help getting the generator lower down on the adjustment bolt. Stay tuned!

Hanno

[Hanno Spoelstra]

Originally Posted by Hanno Spoelstra

While the B52 belts are 35 mm shorter, it will help getting the generator lower down on the adjustment bolt. Stay tuned!

Well.... Tried fitting the B52 belts yesterday, but they don't fit. With the generator in the lowest position, the belts would not fit over the pulleys. I might have been able to force them on with a screwdriver, but there should be enough slack to fit them by hand.

So I fitted an unworn BTR 51050, which is a B53 size. Those went on easily, but the generator still sits high on the adjustment bolt.

Maybe I should try a B52-1/2.

H.

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[rob love]

I just went through this exercise of one belt being at the outer limit, and the next available size down was just too short. In my case it is an 8BA engine squeezed into a carrier.

The flatheads with the single water pump pulleys only had a bushing for the water pump shaft. As such, the belts were elft with considerable deflection. Since our CMPs had the heavy duty double pulley water pumps with a more conventional bearing on the pump shafts, you can get away with a little tighter belt.

The new belt will stretch considerably in the first 10 minutes of run time. Rather than forcing it on with a screwdriver, get it started onto the upper pulley as best you can and then turn the fan to get it to take. Once it is on the pulley, you may find it is not that bad. After 10 minutes of run-time, you may find it stretched into specs.

[Hanno Spoelstra]

Originally Posted by rob love

The new belt will stretch considerably in the first 10 minutes of run time. Rather than forcing it on with a screwdriver, get it started onto the upper pulley as best you can and then turn the fan to get it to take. Once it is on the pulley, you may find it is not that bad. After 10 minutes of run-time, you may find it stretched into specs.

Thanks for the tips, will give it a try again.

I will be living in my truck and doing a lot of driving during 13-22 september, so I'm sure I will get to learn much more about the intricacies of a Ford CMP

Hanno

[rob love]

Personally I love the Ford flatheads, with one exception. The charging systems on the early ones are so marginal (this goes for most 6 volts vehicles actually) that at some point you will be tempted to use the hand crank to start it. Twice my old KL whacked me in the elbow, and after I finished doing the dance of pain, she just sat there purring away, unapologetic and oblivious to the pain she caused me.