Greetings oh wise and witty CD board,
In what my brother hopes will steal the limelight from the "Locked or Freewheeler" topic, (He's a freewheeler, I'm a locker but we have peace between us) I wondered if any of you with the Universal 5424 motors know if the main pulley will accept a 1/2 inch belt for a new alternator? The belt for the present alternator, which I believe is original (The alternator guys, not the belt), is 3/8". To my eye it seems as it might but I know some of you have upgraded. Any thoughts? He really wants me to get this Ferris HO alternator installed this spring.
Thank you and happy new year to all,
Paul
p.s. It is tradition to drink Scotch and think boats on New Year's day up here; I guess our football teams ain't in it.
Alternator Belt Size Question
Moderator: Jim Walsh
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Steve Laume
- Posts: 4127
- Joined: Feb 13th, '05, 20:40
- Location: Raven1984 Cape Dory 30C Hull #309Noank, CT
- Contact:
Definitly go bigger if you can
I switched to an 80AMP Balmar last winter. I have a Universal 20, with a 3/8" belt. It meets Balmar's recommendations but it has to be kept really tight. That nice white alternator has a layer of black belt dust all over the front of it. My belt runs from engine around fresh water pump and alternator so all of these pulleys would need to handle a larger belt or two if I made a change. I think a double belt has the most appeal. Even if you lost one you would still keep turning the water pump. At least for a while. I was just thinking about this problem SAT while I was at NAPA. I picked up a plastic squirt bottle of belt dressing. I am going to start this season with a fresh belt and use to dressing to see if it helps to avoid slipping. In fact I think most or all of the problem might have occurred when I first started running the engine with the new ALT. Once I noticed the dust I tightened it up a bit more and kept checking throughout the season. Do new belts strech? I am still very happy with the new ALT, smart regulator, start battery, echo charger and battery monitor setup, Steve.
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Oswego John
- Posts: 3535
- Joined: Feb 5th, '05, 20:42
- Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1
New, Larger Alternator
Steve Laume wrote:
Once I noticed the dust I tightened it up a bit more and kept
checking throughout the season. Do new belts strech? ] Quote
Steve,
Most modern day vee belts have embedded steel wire cores which prevents little to no stretching.
What seems to be the belt stretching is actually the sides of the belt wearing and abrading, causing the black dust. As the sides wear, the cross section of the belt becomes thinner. This wear allows the belt to sink deeper into the pulley's groove which will make the belt become loose.
The loose belt causes inefficiency, and the slipping belt heats up which aggravates the cycle and encourages more wear. Misaligned pulleys will also cause abrasion.
Over the years, I have believed that a new vee belt will sit proud above the outer surface of the pulley. In time, with normal wear, the belt's outer surface will sink below the lip of the pulley. When this occurs, it's time to replace the belt
One byproduct of overtightening the belt is causing excessive, premature wear on the pully shafts' bearings.
If space permits, I would think that the installation of double belts might prove worthwhile in the long run.
My 2¢
O J
Once I noticed the dust I tightened it up a bit more and kept
checking throughout the season. Do new belts strech? ] Quote
Steve,
Most modern day vee belts have embedded steel wire cores which prevents little to no stretching.
What seems to be the belt stretching is actually the sides of the belt wearing and abrading, causing the black dust. As the sides wear, the cross section of the belt becomes thinner. This wear allows the belt to sink deeper into the pulley's groove which will make the belt become loose.
The loose belt causes inefficiency, and the slipping belt heats up which aggravates the cycle and encourages more wear. Misaligned pulleys will also cause abrasion.
Over the years, I have believed that a new vee belt will sit proud above the outer surface of the pulley. In time, with normal wear, the belt's outer surface will sink below the lip of the pulley. When this occurs, it's time to replace the belt
One byproduct of overtightening the belt is causing excessive, premature wear on the pully shafts' bearings.
If space permits, I would think that the installation of double belts might prove worthwhile in the long run.
My 2¢
O J
Depending on the size of your altinator, upgrading to a 1/2" belt could really make a difference. But if its really large, as suggested, a double belt is even better. But once your getting into double belts you can do a single 1" serpentine belt in the same space which is far superior to a double.
As for the pulleys, if your have a pully for 3/8" then do not try to use anything else on it, you need to replace all pulleys that particular belt uses in order to change size. It can be costly, especially with an older engine for which standard pulleys in larger sizes may not be an off the self option (your looking at custom machined stuff here, spendy).
I would try a few other things as well, some belt dressing (you can buy it at napa) can help with slippage. Also check alignment, this can be a big problem. If your not ready to spend the money on all new pulleys to go up in belt size, then most smart regulators these days have amp managers on them, you can set your altinator to run at say 80% output max, so you reduce the max load on the belts.
As for the pulleys, if your have a pully for 3/8" then do not try to use anything else on it, you need to replace all pulleys that particular belt uses in order to change size. It can be costly, especially with an older engine for which standard pulleys in larger sizes may not be an off the self option (your looking at custom machined stuff here, spendy).
I would try a few other things as well, some belt dressing (you can buy it at napa) can help with slippage. Also check alignment, this can be a big problem. If your not ready to spend the money on all new pulleys to go up in belt size, then most smart regulators these days have amp managers on them, you can set your altinator to run at say 80% output max, so you reduce the max load on the belts.
Russell
s/v (yet to be named) Tayana 42CC
s/v Lady Pauline Cape Dory 36 #117 (for sale)
s/v (yet to be named) Tayana 42CC
s/v Lady Pauline Cape Dory 36 #117 (for sale)
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moctrams
- Posts: 583
- Joined: Jul 21st, '06, 15:13
- Location: 1982 Cape Dory 30C,Gabbiano,Hull # 265,Flag Harbor,Long Beach, Md.
Balmar 3/8"X 4" pulley
Replaced the old alternator on "Gabbiano" with a new Balmar 621-70-SR-1G as sugggested in various posts. Tried to obtain the 3/8"X 4" pulley from the two companies listed in the Balmar doc. One company (HS Marine Parts) sold the business and could not help. The other was unresponsive. Called Balmar direct and ordered Balmar pulley, part # 12-4031 for $75.00.