• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

TR2/3/3A TR3A Radiator Clearance

Share this page

angelfj1

angelfj1

Yoda
Country flag
Offline
We did a trial fit of the radiator yesterday. The shop temp was maybe 40F so we were kinda working fast but we are concerned by the lack of clearance between the fan blade and radiator. Considering vibration, normal flex, etc, what is considered a safe amount of clearance to prevent the fan from crashing into the rad. Were there variations in radiators/dimensions? Have you experienced this issue? Considering the engine can't be moved to the rear and the cross member in front of the radiator. Any suggestions?
 
My recollection of fan/radiator clearance in the TR3 is "barely enough room to squeeze the fan belt between them." Figure about 3/4". Fan belt replacement without that much clearance isn't really possible.

You're right. Neither the motor nor the radiator is really adjustable for this. If you're much tighter than that, maybe you have the wrong crank extension. I know that TR3 and TR4 are different. I can't remember for sure, but I <span style="font-style: italic">think</span> that TR4 is longer. If that's right, and you're trying to stuff a TR4 extension in there, that could explain a too tight fan/radiator situation.
 
Yes, just been and had a look and there is between 1/2 to 3/4 of an inch clearance between the fan and the radiator on my car.
 
Hi Frank,

I've heard of an owner removing the captive nuts on the bottom mounts and slightly elongating the holes, then re welding on the nuts. I think you can pick up about 1/4 to 3/8" extra forward clearance before the bottom front of the radiator touches the cross bar.

He reckoned it was well worth the trouble at wide fanbelt changing time.

Incidently, a few of us here in our hot climate have fabricated up scoops from sheet aluminium to direct air up into the bottom section of the radiator. Painted out matte black they don't get noticed, and seem to help cooling when the car is on the move. Those entering concours events just unbolt them the day before.

Regards,

Viv.
 
Viv et al:


<span style="text-decoration: underline"><span style="font-weight: bold">PROBLEM SORTED</span></span>
Based on a tip from th Forum, it seems that there was a design change in the crank-fan extension when the TR4 was introduced. This was required to accomodate the longer TR4 chassis. We looked in the spare parts bin this morning and actually found three styles of extension; short cast iron at 3 3/4 -inch fitted to TR3/3A, long cast iron at 4 3/8-inch fitted to TR4/4A and long aluminum at 4 3/8-inch which we believe may have been fitted to the TR2. Can anyone confirm the TR2 unit being aluminum and 4 3/8-inch long?

<span style="font-style: italic"><span style="font-weight: bold">After checking, we confirmed that the extension on our project 3A is the long one, 4 3/8-inch which is incorrect.</span></span> This explains the fan clearance issue. So, yet another detour but after a little glass beading and some paint on the short cast iron extension, we will have gained 5/8-inch which should resolve this problem.

Thanks for all of your suggestions!
 
vivdownunder said:
Hi Frank,

I've heard of an owner removing the captive nuts on the bottom mounts and slightly elongating the holes, then re welding on the nuts. I think you can pick up about 1/4 to 3/8" extra forward clearance before the bottom front of the radiator touches the cross bar.

He reckoned it was well worth the trouble at wide fanbelt changing time.

<span style="font-style: italic"><span style="font-weight: bold">Viv: Thanks for the tip but fortunately, we will not have to do that!</span></span> <span style="font-style: italic"> fja</span>

Incidently, a few of us here in our hot climate have fabricated up scoops from sheet aluminium to direct air up into the bottom section of the radiator. Painted out matte black they don't get noticed, and seem to help cooling when the car is on the move. Those entering concours events just unbolt them the day before.

<span style="font-style: italic"><span style="font-weight: bold">Viv: Is the scoop in addition to the fibre-board fan shroud added during TR3A production and availabe through dealers?</span></span> <span style="font-style: italic">fja</span>

Regards,

Viv.
Click to expand...
 
Frank-

There was an optional aluminum extension I think for the 4/4A - my guess is that is what you have in the parts bin?

Don't forget, you'll need to scrounge your parts bin for a shorter dog bolt too!

Randy
 
angelfj said:
...long aluminum at 4 3/8-inch which we believe may have been fitted to the TR2. Can anyone confirm the TR2 unit being aluminum and 4 3/8-inch long?
Click to expand...
If it's the long size, it's for TR4 and later. TR2 and TR3 would be the same "short" length.

Dang! I was right...
Lucky guess, eh?
 
Back
Top