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Tensioner range question

Over the weekend I upgraded the alternator on my Thunderbird from a 2G to a 3G alternator. The 3G alternator has a larger pulley than the stock 2G alternator. The stock size serpentine belt fits with the new alternator but is a little tighter. After installing it the arrow on the tensioner points to the "A" in RANGE



With the stock 2G alternator the arrow pointed to the "N" in RANGE. Having the belt slightly tighter shouldn't hurt anything correct? After all it's still in the RANGE area on the tensioner, just tighter.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Tensioner range question

Reply #1 –
Prob fine but you could use the smaller pulley...


What does bother me is it appears the tentioner has a large gap at approx eight o'clock, while there is very little at two... This would indicate it's bushing is rather worn, likely pulley is slightly pen 15ed as well...

Tensioner range question

Reply #2 –
Quote from: TurboCoupe50;451371
Prob fine but you could use the smaller pulley...


What does bother me is it appears the tentioner has a large gap at approx eight o'clock, while there is very little at two... This would indicate it's bushing is rather worn, likely pulley is slightly pen 15ed as well...


The pulley that is on the alternator is allowing it to charge fine. At idle in park (700 rpm) it's putting out 14.4-14.5V. With the A/C on high, headlamps, and radio on output only drops to 14.2-14.3V at idle. I figure as long as the tensioner arrow points somewhere in that little RANGE box it shouldn't overload the accessories.

The tensioner gap is an optical illusion created by the camera perspective. The space around the tensioner is even all the way around. I didn't take the picture head on because then the viewer wouldn't be able to see the tensioner RANGE section. It would be blocked by the radiator shroud.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.
 

Tensioner range question

Reply #3 –
You'll be fine with that size pully. With your gear and convertor you won't notice the difference.

PS:  I routinely pull on the belt when I'm under the hood to keep the tensioner free from seizing.
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing: