TR5/TR250 Downside to putting TR250 fan on TR3

[TuffTR250]

I installed a yellow TR250 engine fan on my TR3A. I like the way it moves the air (versus the old metal fan) even though I had to install it backward so it would clear the radiator. Now I just found out the downside. The fan is so close to the big pipe brace that I can't get the belt out and over the fan to remove it. I had no problem getting the belt off the pulley since just turning the steering wheel clears the steering rod. Does anyone have any suggestions on how to get the belt out past the pipe brace to put a new belt on? I sure hate to think of removing the cowl, the radiator, and the fan just to get the fan belt off and new one on.p.s. Has anyone installed a 13 blade red TR6 fan and adapter on a TR3, and does that leave clearance in front and behind the fan for changing the belt?Regards,Bob

 

[Geo Hahn]

For a time I had a yellow TR6 fan on my TR4 and to make it fit I had to install it backwards and make a spacer about 1/4" thick. If moving the fan forward a bit would solve the clearance issue you might consider that. To make the spacer I used a piece from a plastic cutting board -- can be found in various thicknesses, easy to work, yet pretty tough stuff. Of course adding a spacer will also require 4 slightly longer bolts.

 

[TuffTR250]

Thanks Geo! I may have to bite the bullet and remove the cowl, radiator and fan. And then put a spacer behind the fan. I'm going to see if I can figure out a way to get the belt out the bottom under the big pipe support by turning the engine slowly using the back wheel and trying to get the belt over the fan blade by blade. Not sure if that will work, but I'm going to give it a try tomorrow. Regards,Bob

 

[Geo Hahn]

FWIW - I have replaced the stock fan on the TR3A with the radiator etc in place... working from below. It was tight and I had the car on the lift, but it was doable. Don't know if your set up would allow this. Hopefully that 'one blade at a time' will work.

 

[Perrymip]

You might remove the six bolts and remove the cross-member. This require some contortion, and you will likely need to lift the front wheels to take the tension off the front suspension.

 

[mallard]

If you are using the original style un-cogged belt you might want to try the Dayco Top Cog 24380 belt. It's just as wide but not as thick and much more flexible. Rock Auto sells the belt or just look for Dayco 24380 on-line.

 

[TuffTR250]

It worked to get the belt off from the bottom one fan blade at a time. I put the car on jack stands, took the spark plugs out of the engine, blocked one of the back wheels, put it in gear, and used the other wheel to turn the engine. I would not have been able to force it out except that the plastic fan is flexible and so is the belt.Regards,Bob

 

[Geo Hahn]

...I put the car on jack stands, took the spark plugs out of the engine, blocked one of the back wheels, put it in gear, and used the other wheel to turn the engine...

Imagine trying that along the roadside. You will want an emergency belt or at least a length of stretchy rope on board just in case. I have an old )narrow) bicycle tire tube I've been meaning to see if I could fashion into something suitable for a get-me-to-next-exit repair.

 

[TuffTR250]

Thanks Geo! That's a really good idea to have an emergency fan belt. I think I've seen some place where you can buy a thin one that goes around the pulleys and then locks together. Regards,Bob

 

[HarryL]

Now that's interesting ! Keep us informed if you find where we can get one of those belts.
Harry

 

[Geo Hahn]

I found one at the FLAPS -- brand was Victor V-320:

Have never had to use it (goes in my non-British car). I've shimmed my TR engines high enough that changing a stock belt should be easy enough.

Seems there is also a version on ebay.

Though for the thrifty/crafty -- I once drove from Kirkland AZ to the top of Mt Lemmon with just a rope tied around the crank pulley and water pump when the generator seized. Pretty easy to cinch up a 1/8" nylon rope tight enough to spin that pump.

 

[TR3driver]

Now that's interesting ! Keep us informed if you find where we can get one of those belts.
Harry

Most industrial supply houses should have them; though the cost is high and you generally buy by the foot. See the "Twist Lock" listing under "Adjustable length V-belting" at
https://www.mcmaster.com/#catalog/119/1045/=mwo6nz

I have not tried it, but I believe size "C" (7/8" width at the top) should fit the stock TR3 pulleys well enough.

Twist lock belts get a lot of coverage among those who play with vintage machine tools. My old Atlas lathe, for example, requires pressing the spindle out of the headstock in order to change the belt. Lots easier (and safer) to use a Twist Lock. As an added plus, they are claimed to improve surface finish by reducing vibration.

 

[Perrymip]

I used the yellow TR6 fan for twenty years or so and had only positive experience. I, too, mounted it backwards, and, with less imagination than required for the spacer described above, I simply used four stacks of washers to bring it forward enough to clear the cross-bar for belt changing.

Has anyone installed a 13 blade red TR6 fan and adapter on a TR3, and does that leave clearance in front and behind the fan for changing the belt?

I have, probably foolishly, switched to the late red fan with adapter. Issues are about the same as with the yellow fan. The 13 blades certainly pull the air through and this fan seems to me very desirable for heavy traffic. I'm not certain what violence I've done to the engineering, but I did have to reverse the mounting adapter in order to fit the fan between the cross-bar and the radiator. Check with me in another twenty years for a report. The space between fan and radiator in this arrangement is, of course, very tight.

 

[vivdownunder]

Easy to remove the old belt by cutting across and making it into a strip. Then there's only one hard job (fitting the new belt) instead of two.

Viv.