If you only have one pump and that pump draws water from outside of the boat, then you have a seawater cooled engine even though you are in fresh water. Generally the term freshwater cooled refers to an engine that has a closed cooing system with a heat exchanger.
Tightening Engine Belt on Universal 5411
- Thread starter shank
- Start date
I did basically the same thing. I had some difficulty finding exactly what I wanted, there isn't a lot of room on a 3YM20. I ended up ordering from McMaster-Carr.
This is with a 1" longer belt and the original adjuster. I ran out of adjustment but a shorter belt wouldn't fit
This is with the new adjuster and a 2" long belt. Works great!
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Remember over tensioning a v-belt is just as bad as under tensioning.
V-Belt inspection remember to turn the engine off
V-Belt inspection remember to turn the engine off
- Check all the drive belts for fraying or cracking. If the belt was slipping the outer edges may be glazed, or shiny, the belt needs to be replaced. Visually look at the belt, inspecting it for any sign of cracking or worn-out edges. Replace the belt if anything abnormal is found.
- Inspect all the pulleys for rust or unusual wear or misalignment. If out of alignment, you will need to determine the cause of the condition.
- Check the tension by using your forefinger and thumb and deflecting the belt downward. Always make your check in the middle between two pulleys.
- If the belt can be deflected downward more than 1/2 inch or the slack is excessive, the belt needs adjustment.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,261
So my dad told me a story about goldiskipper and the three V-belts.
- One was too tight and it destroyed the bearings and blew dust all over the engine room
- One was disappointingly loose.and I flapped I the air. Failed to turn the alternator or water pump. Eventually the engine ground to a halt.
- and One was just right. It made the engine hum carrying the crew and skipper where
There's a port on a western bay
And it serves a hundred ships a day
Lonely sailors pass the time away
And talk about their homes
And there's a girl in this harbor town
And she works layin' whiskey down
They say "Brandy, fetch another round"
She serves them whiskey and wine - the Sailors are happy.
And the funny thing is my love for songs like Brandy and Southern Cross help me decide that I was a sailor stuck in a corn field in the middle of no where Indiana. Joined the Navy back in '78 and never looked back.
Just one more idea that might work depending on what you have around and your engine configuration- I’ve had success using a reversible trigger clamp to push the alternator away. Something like DEWALT 24 in. 300 lbs. Trigger Clamp with 3.75 in. Throat Depth DWHT83194 - The Home Depot
That's a great idea. I'm going to check out one I got from Harbor Freight to see if it fits. It would be easier than using the jack screw setup I cobbled together.
12 in. Ratcheting Bar Clamp/Spreader
Amazing deals on this 12In Ratcheting Bar Clamp/Spreader at Harbor Freight. Quality tools & low prices.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,261
@Richard19068 and @shank that article by MaineSail brings three issues to light.
- The lack of proper sized bolts used in attachment of the alternator to the engine, with need of a drift bearing in some installations
- The need to have a proper adjustment arm with an adequate bolt and locking nut to secure the alternator in position.
- the impact on performance and wear when alignment is not addressed.
Of course. The bar clamp / spreader would be to get the belt tensioned. Keeping it that way is another issue.
The OP said he had trouble tightening the belt.
"I have trouble tightening the engine belt on this engine. ...it seems no matter how hard I push on that alternator on the bracket to slide it over I can't get enough pressure on it to tension the belt properly. "
Using two hemi joints and a jack screw or a turnbuckle solves both issues. It also make tensioning the belt easy.
A word of caution that I think may have been mentioned: too much tension can actually be worse than too little! These belt systems weren't designed for high output alternators, and if you need to increase the tension to stop slippage it may result in too much side load on the water pump. It will kill the pump. I wish I had the energy to design a mount, etc., to run a sub-HP belt for the water pump and a serpentine belt to the alternator. I'd also install a belt tensioner idler pulley for the serpentine belt.
That said, it is my intuition that a serpentine belt conversion kit will solve this, as you don't need that much tension on the serpentine belt to make it work. However, a kit is in the neighborhood of $500.
That said, it is my intuition that a serpentine belt conversion kit will solve this, as you don't need that much tension on the serpentine belt to make it work. However, a kit is in the neighborhood of $500.
Thus far no one has mentioned the possibility the belt is past its time.
Belts can stretch a bit and if they become glazed they can slip. Perhaps trying a new notched belt (like @SycloneDriver's) will solve the problem. The notches increase the contact on the pulleys and should reduce the tension needed to drive the alternator. Going down one belt size might also help.
The alternator appears to be the original alternator which is probably a 35a or 55a alternator. It should be easily driven by a belt that is new and not worn.Adding a larger washer, either a lock washer or a double thick fender washer, will also help maintain the tension. For an alternator this small there should be no need for a serpentine belt.
Belts can stretch a bit and if they become glazed they can slip. Perhaps trying a new notched belt (like @SycloneDriver's) will solve the problem. The notches increase the contact on the pulleys and should reduce the tension needed to drive the alternator. Going down one belt size might also help.
The alternator appears to be the original alternator which is probably a 35a or 55a alternator. It should be easily driven by a belt that is new and not worn.Adding a larger washer, either a lock washer or a double thick fender washer, will also help maintain the tension. For an alternator this small there should be no need for a serpentine belt.
I actually found this not to be the case. While the standard adjusting bolt held the tension on a 90 a alternator, after changing to a 165a alternator and adding a serpentine belt the adjusting bolt could not maintain appropriate belt tension.
That's interesting. Not my experience. I have the Balmar serpentine 'upgrade' with a 125A Powermax alternator. It didn't seem to take that much tension at all. It's a 10 groove belt, as I recall. That said, the contact on the water pump pulley i snot much, either, so I don't think I'm putting much of a side load on it.
Your alternator is higher capacity than mine, and I'm soft-starting mine, and limiting output; I'm down to a limit of 35A now, I think, due to the max charging current spec of the FLA bank. I think you have LFPs, and are probably driving them hard, no?
Not yet. I had FireFlys with a max charge of about 100a, typically running at about 60-80a. Also have a Balmar 618 regulator with the soft start. The original adjusting system would only hold the alternator in position for about 8-10 hours if that long. After adding a belt buddy, it has been hundreds of hours with no slippage.
I have an M-12 and I could never get it as tight as I wanted, the so called 1" sag spec. It threw a lot of dust also. I finally decided not to do it one season, checked to see if it was outputting ok and that was probably 10 seasons ago. Never touched it since. Net is at least on my M-12 it can live with more slack than the manual specifies.
How much current are you pulling from the alternator? Also, if it's throwing dust the pulleys are probably misaligned.
That's good to know that's not just my engine with the floppy belt. I'm not seeing any dust and I haven't done an alternator test.
I ended up creating a jig with the blocks of wood and a piece of threaded rod like the one @dlochner posted and it worked really well. I also bought a 10.5" turnbuckle for $4.50 and rounded the ends off like @Ralph Johnstone suggested and I think that will work well too but I haven't tried it yet. So my belt is tight now (moves about 1/2" when pushed in the middle) but we'll see how long it stays that way. I put a star lock washer and some Loctite Threadlocker blue on the bolt so maybe I'll get lucky this time.
Thanks again everyone.
I ended up creating a jig with the blocks of wood and a piece of threaded rod like the one @dlochner posted and it worked really well. I also bought a 10.5" turnbuckle for $4.50 and rounded the ends off like @Ralph Johnstone suggested and I think that will work well too but I haven't tried it yet. So my belt is tight now (moves about 1/2" when pushed in the middle) but we'll see how long it stays that way. I put a star lock washer and some Loctite Threadlocker blue on the bolt so maybe I'll get lucky this time.
Thanks again everyone.
There is always the option to go with a shorter belt. This may make adjusting easier.
13.7 volts. Cannot read the current, but getting a good charge always. An M-12 experienced mechanic stated that some dust throw is normal for this engine.