TR3B FAN BELT & ELECTRIC FAN.

[COLIN BLUNDELL]

COULD ANYONE PLEASE ADVISE ME ,I WANT TO TAKE THE ORIGINAL WIDE FAN BELT AND FAN OFF MY TR3B AND FIT THE NARROW BELT AND PULLEYS THEN FIT AN ELECTRIC FAN CAN THIS BE DONE WITH OUT TAKING THE FRONT PANEL OFF THE CAR ,ALSO IS IT BEST TO FIT THE NEW FAN AT THE FRONT OF THE RAD OR BEHIND THE CAR IS STILL ON POSITIVE EARTH ELECTRICS THANKS Colin.

Edited January 3, 2016 by COLIN BLUNDELL

[EdwinTiben]

My 2cents.. Keep the original fan. Have experienced problems with a Well known fan. I was glad i had my mechanical fan as a backup.

Have kept the original wilde belt too, no problems with that, just dont overtension it.

 

Your question: no, you Will have to remove the apron and radiator.

If you proceed i would fit it behind to keep as much radiator out in the open.. Buy the correct electrical fan, with suction instead of blowing.

[Richardtr3a]

I kept my original fan and the wide belt. It has to be loose to the touch so that the water pump and dynamo do not wear out quickly. The fan removal can have an effect on the balancing of the crankshaft and it can break.

 

Therefore fit a Kenlowe electric fan and thermostatic switch to the front of the radiator. Some fans have fittings through the fins of the radiator. I pushed a plastic tie through and punctured the rad. When it was being replaced I had a new upgraded core fitted with offset finned columns

 

The overheating problems were solved. It does mean removing the front panel. But you can deal with the rust, the electrical connections, the extra earth engine strap , check the steering box, and fit new engine mountings which are all accessible and easy. Once you replace the panel you will never get in there again without a major hassle.

 

It all worked for me many years ago and I can find the radiator specialist in Surrey,if you need him .

 

Good luck

 

Richard & H.

Edited January 2, 2016 by Richardtr3a

[Motorsport Mickey]

Colin,

 

Remove your e mail address, you have to expect all forums are hacked and monitored by "auto bots" (automated scanning computers) you will be swamped with spam mail and con lists. Chat through the Personal Messenger postings with other members if need be, click triangle next to your name at the top of the page.

 

Mick Richards

[RobH]

Yes, as Edwin says Colin - to get at the crank bolt the radiator has to come out and that needs the front apron off. I had to do that some while back to replace the chain tensioner and it took about a day to strip it all down given the usual business of rusted bolts and the awkwardness of access to some of them. You have not said what the reason is for wanting to fit a narrow belt since it appears you are intending to retain the dynamo rather than change to an alternator ?

 

Its possible to use a modern wide belt with the original setup if that is your reason. A 17mm 'cogged' type works just fine and is a lot slimmer in profile which means changing it is much easier than with the the old stiff fat type given the tight clearance between the steering rod and the pulley.

 

Rob

Edited January 2, 2016 by RobH

[Andrew Smith]

Colin,

 

I would recommend you keep the original fan as a contingency and consider a Kenlowe or Revotech pusher fan with thermostat and a manual switch under the dashboard. I've had absolutely no problems with the Kenlowe, but it's nice to know I have a contingency if needed.

 

If you can find a 6-blade tropical fan I would also fit on of those; the combination of that and the Kenlowe keep my 3A from overheating in 40 DegC a few years back in France.

 

Edit: Also make sure you fit the radiator ducting as this is essential for air flow - I've seen so many 3As without it and owners wondering why their cars still run hot.

 

Here's my 12" Kenlowe:

 

 

 

And the 6-blade tropical fan:

 

 

 

Cheers

Andrew

Edited January 3, 2016 by Andrew Smith

[littlejim]

Contrary to a lot of the above I took the fan off (useless when you are stopped, which is when the heat builds up) and fitted a davies-craig fan in front of the radiator. (It switches on when you are stopped).

Taking the fan off probably gives you a couple of extra horse power.

I stuck with the wide belt out of iggorance about the benefits(??) of changing it.

I also got rid of the water pump and fitted an electric water pump.(More HP ??)*

Copes OK with the OZ summers and mountain passes.

 

* only runs full bore when required.

Edited January 3, 2016 by littlejim

[tim hunt]

I fitted a second hand Kenlowe kit (£17) to my 4A forty years ago. I removed the mechanical fan at the time and fitted the Kenlowe in front of the rad to push. I retained the original wide belt and pulleys. I may be tempting Providence but the motor is still working fine, the fan only cuts in after extended periods at idle, in very slow moving traffic at higher ambients, or on long severe alpine climbs using lower gears. Many years ago I was fortunate to pick up another complete kit for my car at a car boot for £2 - it was all in a box of bits and the seller had no idea what it was! At least it gave me a spare motor just in case. I have replaced the original temperature sensor and manual override switch and that's all in forty years.

 

Tim

[mikej]

My own experience is that the e-fan resolved over heating when stationary on hot days and improved warm-up on cold ones. The 'standard' fan actually impedes air flow above 50mph and allegedly liberates 1HP when removed!. Fan can be fitted without removing the front but it's a knuckle scraping experience. My Pacit fits snugly between the rad and a Revington thin belt conversion. Only issue has been alternator pulleys working loose, not sure aluminium is the best material for these.

 

go for it!

Mike

[Lebro]

Just to add to the "No mechanical fan" theme, I went narrow belt, alternator, harmonic damper, Revotec sucking fan route when I rebuilt my '3 two years ago. Only problems I have had was a failed Revotec temperature sensor, which I have now replaced with an Otter switch in the steel part of the bottom hose.

 

Bob.

[RogerH]

This should start an argument !!!

 

The mechanical fan uses far more than 1BHP ALL the time.

Removing the mechanical fan will NOT break your crankshaft - can anybody prove it does?

Fitting a Harmonic damper on the crank pulley - WHY??? the generally available damped pulleys were not designed for the TR - what are you damping?

 

I use DOT4 in the brakes and Penrite 40 grade oil in the OD

 

Roger

[Lebro]

Is this a five minute argument, or the full half hour ?

 

Bob.

[tim hunt]

I'm with Roger - probably tempting Providence again to mention it but I removed the fan hub extension along with the mechanical fan when I fitted the Kenlowe 40 years ago. I am still waiting for the original crankshaft to break after ~ 200K miles despite the prophets of doom. I only removed the extension because it simplified changing the original type thick fan belt. On my car, despite new engine mounts it was impossible to squeeze a replacement fan belt between the extension and the rack tube; to do this it was necessary to loosen the mounts and jack the engine up a little to give enough clearance. Not the simplest job at the roadside.

 

Tim

[RogerH]

Hi Bob,

a full half hour over a pint; Mines a pint of Shere.

 

 

Roger

[Lebro]

Fair enough.

 

Bob.

[Malcolm Tatton]

I have 2 engines, built by (different) respected well known builders who have been successful in competition. One has a damper, the other does not. One said that it was not worth the risk so best to fit one, the other said that in his opinion a properly balanced and built engine does not need one and he advised against it.

 

So I won't be joining you two for a pint......

[Lebro]

It would have been a long journey anyway !

 

Bob.

[Fireman049]

I fitted a Kenlowe electric fan to my Mini Cooper in 1966 and it's still going strong!

It was briefly fitted to an MGA for a while then re-fitted to the Cooper.

 

My 1965 'E'-type Jaguar is also fitted with a Kenlowe.

 

My 3A is fitted with a 14" electric fan but I don't know what make it is?

 

Tom.

 

[Dave Larnder]

Andrew et al.

 

My Kenlowe is a suction type, and that is a better set up in my opinion as the amount of flies, butterflies and othe flying debris is hard enough to get out ot the rad fins, let alone the Kenlowe fan blades in your case. This was apparent on my return from Stelvio, 18 months ago, but was easy enough to clean with the grill out, and of course with the ali ducting preventing the flying debris getting around the internal wings etc. You of course have the rain to keep yours clean.

I have no mech. fan, but narrow belt, alternator and r&p steering. and as for the 40ºC plus day temps, that is a problem confined to the past, I do have a manual override and switch it on in slow moving traffic to be on the safe side.

 

Dave

 

 

[Ian Vincent]

On the theme of overheating, I had an uprated water pump that didn't seem to be doing it's job so I replaced it with an original one that I had rebuilt myself paying close attention to the clearance between the back face of the pump gallery and the pump impeller. The result is a pump that seems to work more effectively at low revs rather than the 'uprated' one that had so much clearance around the impeller it couldn't possibly have been very effective at low revs. Certainly the engine takes longer to get up to the point at which the electric fan cuts in than it used to.

 

I suspect that the uprated impeller with the increased number of curved blades is designed to work at higher speeds without cavitation.

 

Rgds Ian

[Guest]

Pacet suction fan on mine. Uses less current than the well knows Kenlowe. There's thermo switch in the downpipe (Moss) and an override switch with a control light on the dash. It's a good idea to use a relay for the fan, since it draws a lot of current.

 

I also use a narrow belt, Denso fan from a Suzuki (as can be found these days on Kubota gardening machines) and no harmonic damper. I've been on the fence for quite a while: harmonic damper yes/no. It was something from the RevingtonTR site that pulled me over to the non dampened side: http://www.revingtontr.com/shop/product_display.asp?mscssid=DQ8KN3CMF85G8M82TDE2LL62CEW00QA9&CarType=TR3&ProductID=RTR1208K

 

 

 

A word about Harmonic dampers versus solid machined crank pullets
We don t usually use Harmonic dampers on the crank. If one is fitted to an engine we are working on and it is not giving problems we will leave it there.
I have raced my TR2 for over 30 years with a standard type crank without a rubber mounted pulley. I recon I have done 200,000 miles in the car a lot of which would be racing, hill climbs, sprints, rallies as well as fast road work and I haven t had a problem yet. The issue as I see it is that engine manufacturers go to a lot of trouble to design a harmonic balancer when an engine is designed to get rid of unwanted harmonics. Here is the clue; harmonics are frequency dependent so the damper has to eliminate specific frequencies. Obviously not all engines produce the same harmonics and therefor one damper does not fit all. In fact you could put a damper on and introduce unwanted harmonics! Who knows what if anything is right for a TR? I certainly don t, so I leave them alone.
Neil Revington