Belt popped off

[Sgt Meat]

This is probably a stupid question, but my belt on my Merc 3.0 popped off, not broken and I need to know what is the easiest way to reattach. I would assume I could just loosen the bolts on the alternator and reattach it, then apply tension with a pry bar or large screwdriver while tightening the bolts back down. Does this sound correct? I have read many posts on replacing the belt and having to remove motor mounts to do so, but I assumed with it just popping off I could handle it this way. Thanks for the help....great site!

 

[Don S]

Re: Belt popped off

If it popped off, I would bet money the pulleys are all rusty and you have black belt dust all over the front of the engine. Would this be correct? If so, the belt is getting narrower, from the edges being sanded off by the rusty pulleys. Until you sand, clean, and paint the pulleys, you will be loosing belts constantly.

Yes, prying on the alternator and retightening the bolts is how it's done, but DO NOT pry on the aluminum housing.

 

[Sgt Meat]

Re: Belt popped off

Don...that is correct, there is some rust showing so I will be cleaning and painting. Just got the boat a few weeks ago so I am making my check list for things to do. Thanks for your help.

 

[Don S]

Re: Belt popped off

Might want to spend some time up in the sticky threads at the top of this forum.

 

[Sgt Meat]

Re: Belt popped off

So here are some pics of the belt and pulleys....this does not look like any of the diagrams I have seen on here. How is this alternator bolted to the engine? Not thru the top or bottom bolt holes that I can see. Also, look at the wheel on the alternator and how it has been chewed up...what caused that? I know I need to replace that for sure but the other pulleys appear ok and rust free. How should I go about reinstalling this belt?

 

[Don S]

Re: Belt popped off

The upper bracket that holds the alternator tight is missing. Did you remove it?
What is the serial number for your engine? Or maybe even a year? These things have been around since the late 60's and have changed a lot over the years.

Here are the parts that are missing, highlighted in yellow.

 

[Sgt Meat]

Re: Belt popped off

I guess that would have something to do with it popping off huh? No I did not remove it so now I need to get the bracket. Where should I get it from, part # etc. ? Thanks Don. I posted in the non repair forum about trying to identify my engine. You have responded to that post as well...I posted pics of the numbers off the engine but could not find a plate.

 

[Don S]

Re: Belt popped off

Yeah, found it and answered it too.

 

[Sgt Meat]

Re: Belt popped off

Do you think the bolt for the upper bracket that is now missing was being contacted by the wheel of the alternator and caused the notches to the wheel? Figured the previous owner just took it off because I can't locate it anywhere.

 

[markheck1]

Re: Belt popped off

Not the bolt, but I'd say the bracket itself was hittin the alternator fan.....I would wonder if the hole in the engine where it bolted to is ok.

 

[Sgt Meat]

Re: Belt popped off

Yep....now I am stuck. I have loosened the alternator all the way in to put the belt back on but I am still short. Not sure what to do now. The center pulley has four bolts but I cannot get to the bottom pulley. Any ideas?

 

[Pete104]

Re: Belt popped off

Have looked at the stickys? There is alot of good info there!

 

[Sgt Meat]

Re: Belt popped off

Wondering if I take the spacer out if that will give me the room I need?

 

[Sgt Meat]

Belt size help please

Belt size help please

I have a 3.0 Mercruiser that popped off my belt. I loosened the alternator and took out the spacer but could not get it back on. Just a tad short. Gonna get a bigger one but wanted to see what is recommended. Thank you.

 

[Bondo]

Re: Belt size help please

Re: Belt size help please

I have a 3.0 Mercruiser that popped off my belt. I loosened the alternator and took out the spacer but could not get it back on. Just a tad short. Gonna get a bigger one but wanted to see what is recommended. Thank you.

Ayuh,.... If the belt was on it, 'n popped off,... It ain't to short... It was already on there...

 

[04fxdwgi]

Re: Belt size help please

Re: Belt size help please

Sure looks like a huge belt alignment problem caused the belt to MIA

 

[pevaguy]

Re: Belt popped off

Yep....now I am stuck. I have loosened the alternator all the way in to put the belt back on but I am still short. Not sure what to do now. The center pulley has four bolts but I cannot get to the bottom pulley. Any ideas?

I would guess that the former owner removed the top bracket for some reason. Then replaced the correct belt with a shorter one that fit with the alternator flopped over all the way over towards the engine. Your options are to replace the top bracket and use the correct belt, or use a short belt that will fit like it was when you got it. If using the shorter belt you will have to put the belt on all but one of the pulleys, then start it onto the last pulley and bar the engine over to slip the belt onto the last pulley. Good luck.

 

[Sgt Meat]

Re: Belt popped off

Pevaguy,
I believe you are correct because the alternator was all the way towards the engine....I got the belt to the point you are referring to but could not get it the rest of the way. How do I "bar" the engine over to get it on the last pulley? Just curious because I am still going to get the top bracket and then the correct size belt. Thanks.

 

[Sgt Meat]

Re: Belt popped off

The upper bracket that holds the alternator tight is missing. Did you remove it?
What is the serial number for your engine? Or maybe even a year? These things have been around since the late 60's and have changed a lot over the years.

Here are the parts that are missing, highlighted in yellow.

View attachment 162995

Where do I get the parts that I am missing? Could not locate them on the site... thank you.

 

[Sgt Meat]

Re: Belt popped off

Can I get the parts at a local auto parts location?