• The Roadster Factory Recovery Fund - Friends, as you may have heard, The Roadster Factory, a respected British Car Parts business in PA, suffered a total loss in a fire on Christmas Day. Read about it, discuss or ask questions >> HERE. The Triumph Register of America is sponsoring a fund raiser to help TRF get back on their feet. If you can help, vist >> their GoFundMe page.
  • Hey there Guest!
    If you enjoy BCF and find our forum a useful resource, if you appreciate not having ads pop up all over the place and you want to ensure we can stay online - Please consider supporting with an "optional" low-cost annual subscription.
    **Upgrade Now**
    (PS: Subscribers don't see this UGLY banner)
Tips
Tips

TR4/4A yellow fan

nbailey

Member
Country flag
Offline
I am trying to install TRF's yellow TR250 fan on my 67 4A. I was instructed to just turn fan backwards and bolt on. I did not get the bolts fully tightened, before tips of fan were touching the blocks on the steering rack mounts. Has anyone else had this problem? Any suggestions would be greatly appreciated. Thanks
 

Merlin63Tr4

Jedi Trainee
Country flag
Offline
Check and see if some prior owner installed a TR3 hub extension on your TR4A. It is around 3/4 inch shorter that the TR4/TR4A one.
If that's the case see if you can install the fan in "normal" attitude to make the problem go away, check radiator clearance!
For your information the crankshaft bolt for the TR4 measures 6 1/4 inch and the TR3 measures 5 1/2 from under the hex head to the tip.
I'm running a TR3 extension on my TR4 with the "yellow" fan in the normal attitude (not backwards) and everything clears (rack mounts, radiator, etc).

M.
 
Last edited:
OP
N

nbailey

Member
Country flag
Offline
Check and see if some prior owner installed a TR3 hub extension on your TR4A. It is around 3/4 inch shorter that the TR4/TR4A one.
If that's the case see if you can install the fan in "normal" attitude to make the problem go away, check radiator clearance!
For your information the crankshaft bolt for the TR4 measures 6 1/4 inch and the TR3 measures 5 1/2 from under the hex head to the tip.
Im running a TR3 extension on my TR4 with the "yellow" fan in the normal attitude (not backwards) and everything clears (rack mounts, radiator, etc).

M.

Thanks for the reply, particularly the measurements. It appears I do have the shorter fan extension. I just set the radiator back in for a dry fit, and looks like I will only have about 1/4 inch clearance. Do you think this is enough considering possible fan flex etc? Thanks again
 

Merlin63Tr4

Jedi Trainee
Country flag
Offline
That was the clearance I had on my TR4 using the yellow fan and the original (TR4) hub extension, ran it for years like that, your milage might differ...

The fan itself is rigid and in my experience had very little longitudinal flex, the main worry would be longitudinal engine movement, specially if your engine mounts are suspect.

1/4 inch clearance is going to be a problem come "change the fan belt" time and that is why later (when I located a TR3 extension and crank bolt) I went with the thin belt conversion along with the TR3 hub extension.

My TR4 radiator (original) has two sets of mounting holes on each lower bracket, not sure if the TR4A radiators are the same.
I just measured the fan to rad clearance on my TR4 and it is exactly 1 inch using the rearmost set of lower mounting holes.

M.
 

Attachments

  • Rad to fan clearance.jpg
    Rad to fan clearance.jpg
    47.5 KB · Views: 80
  • Rad lower mount holes.jpg
    Rad lower mount holes.jpg
    56.4 KB · Views: 77
  • TR4 engine overview.jpg
    TR4 engine overview.jpg
    81.4 KB · Views: 81
Last edited:
OP
N

nbailey

Member
Country flag
Offline
That was the clearance I had on my TR4 using the yellow fan and the original (TR4) hub extension, ran it for years like that, your milage might differ...

The fan itself is rigid and in my experience had very little longitudinal flex, the main worry would be longitudinal engine movement, specially if your engine mounts are suspect.

1/4 inch clearance is going to be a problem come "change the fan belt" time and that is why later (when I located a TR3 extension and crank bolt) I went with the thin belt conversion along with the TR3 hub extension.

My TR4 radiator (original) has two sets of mounting holes on each lower bracket, not sure if the TR4A radiators are the same.
I just measured the fan to rad clearance on my TR4 and it is exactly 1 inch using the rearmost set of lower mounting holes.

M.
Followup:
After bushings were compressed, I ended up with about 7/16 clearance. Fan is quieter and really moves air. I was ready to reinstall stock fan, so thanks again for your help.
 

Merlin63Tr4

Jedi Trainee
Country flag
Offline
Glad it all worked out!

M.
 
Similar threads
Thread starter Title Forum Replies Date
jfarris For Sale TR6 Yellow Fan - new Triumph Classifieds 0
Zitch For Sale 8 Blade yellow Fan for triumph Triumph Classifieds 2
D TR2/3/3A Have I mounted my Yellow fan backwards? Triumph 10
jfarris For Sale New 8-Blade Yellow Fan and Mounting Kit Triumph Classifieds 0
KVH TR4/4A The Yellow Fan on a TR4 Triumph 4
S TR2/3/3A tr3 yellow fan Triumph 4
PeterK TR2/3/3A TR3 Yellow fan Triumph 1
K TR6 The yellow TR6 fan on a TR3? Triumph 11
SCguy TR4/4A Yellow plastic fan in early TR4? Triumph 8
D TR4/4A TR4 Fan [Yellow Plastic] on a TR3? Triumph 8
L What color yellow for fan? MG 6
Stinky Red Fan vs. Yellow Fan Triumph 28
dwpirkeyjr Red? Bue? Purple? Yellow? Poly Bushings Complete Set For 1979 MG midget 1500 Spridgets 6
K TR6 Need help with Mimosa Yellow Paint Triumph 1
1 For Sale 1980 Yellow MG MGB MG Classifieds 2
W New Yellow Bugeye Spridgets 12
K TR2/3/3A Yellow wire uprated condensor Triumph 1
Jim_Gruber Yellow BE on BAT Spridgets 0
2billydavies TR4/4A yellow blinker light stays on all the time the shuts off when blinkers are used Triumph 2
AN5Sprite Yellow TR6 on Turnpike Spotted 0
DerekJ Primrose Yellow / Black with yellow upholstery Austin Healey 18
F Source for Touch Up Paint for Primrose Yellow? Triumph 3
Mickey Richaud Yellow Alpine Spotted 2
T TR2/3/3A Wisconsin Yellow TR3 Triumph 0
S Lemon yellow early Sprite Spotted 0
aeronca65t Yellow Sprite Spotted 0
tahoe healey Yellow bulbs Austin Healey 17
longbridgehealey Leaf green? Primrose yellow??? Spridgets 22
JamesWilson Yellow Turner Usk A472, Lotus Elite M5, & more.... Spotted 1
M Prim Rose Yellow Spridgets 14
DNK Yellow 6 Spotted 0
ekamm Primrose yellow? Triumph 28
apbos Silver or Yellow Wheels Triumph 10
wangdango TR6 TR6 paint/azteck yellow Triumph 2
T here comes a can-o-worms: yellow fog lights Triumph 19
W Yet another yellow steering arm Spridgets 1
RickB uh-oh... what's it mean when the yellow idiot,,, Spridgets 18
tahoe healey red paint/yellow paint Austin Healey 2
angelfj1 Wedge Awesome Yellow Wedge Beasty - Mere, Wilts UK Triumph 1
T yellow dash light Triumph 3
ronzet California Year Of Manufacture Law Yellow/Black MG 1
T TR4/4A 4A Yellow Blade Triumph 14
Michael Oritt Double yellow? Racing 10
B Nothing mellow about this yellow Austin Healey 1
Webb Yellow Headlamps? Triumph 14
regularman The little'un is now a funny color of yellow Spridgets 32
MadRiver Has anyone made their own yellow-striped hoses? Triumph 3
lawguy The car's yellow, I'm green MG 7
R Red and Yellow lites Triumph 7
Simon TR4a Wedge Yellow TR7 coupe for sale at dealer. Triumph 3

Similar threads

Top