Mercruiser I/O 153 cu Belt Replacement

[redgoat]

I need to know how to replace my drive belt on my 153 cu in 4cyl. 120 Mercruiser I/O. There is no power steering. Just alternator and water pump. The boat is 43 years old and I am the original owner. The belt could be 43 years old too. How do I get the belt past the huge motor mount without messing up the alignment or anything else? I am handy.

 

[Bondo]

Re: Mercruiser I/O 153 cu Belt Replacement

How do I get the belt past the huge motor mount without messing up the alignment or anything else?

Ayuh,... Welcome Aboard,...
Pull the 2 bolts from the mount on the portside, remove the spacer block, change the belt,+ put it back together....

 

[redgoat]

Re: Mercruiser I/O 153 cu Belt Replacement

Doesn't the engine need to be supported prior to the removal of the 2 bolts? Won't it tip without the bolts in place? I notice on the starboard side there is an engine ring mounted on the engine up near the rocker cover. Let me know. If all I have to do is remove 2 bolts and the spacer w/o doing anything else that would be quite simple.

 

[Bondo]

Re: Mercruiser I/O 153 cu Belt Replacement

Ayuh,... I stated how to change the belt,...
If ya wanta Pull the motor, other things need doin'....

 

[redgoat]

Re: Mercruiser I/O 153 cu Belt Replacement

I don't want to pull the motor but I don't want it to fall down either if I remove the 2 bolts. Could we cut the BS and give it to me straight w/o those annoying . . . (dots) Will the motor stay in place w/o being supported after I remove the 2 bolts and the spacer thus allowing me to replace the drive belt?

 

[Bondo]

Re: Mercruiser I/O 153 cu Belt Replacement

I don't want to pull the motor but I don't want it to fall down either if I remove the 2 bolts. Could we cut the BS and give it to me straight w/o those annoying . . . (dots) Will the motor stay in place w/o being supported after I remove the 2 bolts and the spacer thus allowing me to replace the drive belt?

If it needed support, I'd have stated so the 1st time
The total sequence of events is,

Pull the 2 bolts from the mount on the portside, remove the spacer block, change the belt,+ put it back together

 

[JimS123]

Re: Mercruiser I/O 153 cu Belt Replacement

I asked the same question last year when I did mine. Several people said it needed support, several said it didn't.

I used a scissors jack and supported the engine side of the mount before I pulled the bolts. Just snugged it up tight. When the bolts were put back in, it lined up perfectly and the job only took a few minutes.

It very well might not have needed the support, but having it didn't hurt it either.

 

[redgoat]

Re: Mercruiser I/O 153 cu Belt Replacement

Thanks to both of you. I'll give it a try as soon as I get a belt. Imagine my boat with the original 43-year-old drive belt. Can't last much longer.

 

[Fordiesel69]

Re: Mercruiser I/O 153 cu Belt Replacement

Thanks to both of you. I'll give it a try as soon as I get a belt. Imagine my boat with the original 43-year-old drive belt. Can't last much longer.

If it has a 43 year old belt, I wonder what else is also that old.

 

[MToma1]

Re: Mercruiser I/O 153 cu Belt Replacement

This is my 1980 140. But if this is what you are looking at you should be fine. You have two rear engine mounts. Plus the two bolts on the left side, which you might have give some slack to get the spacer out. If I was going to do it I would cut a piece of 2x4 and place it under the edge of the block, or a bottle jack. The engine might shift enough to make it hard to get the bolts back in.

 

[Falco]

Re: Mercruiser I/O 153 cu Belt Replacement

Just did mine on the same motor last week. Didn't need support, didn't tip, and the bolts went right back in..

 

[redgoat]

Re: Mercruiser I/O 153 cu Belt Replacement

UPDATE FROM ORIGINAL POSTER
Removed the 2 bolts w/o any engine support, removed the spacer and then replaced the belt. No engine tip and the bolts went back in very smoothly. Took perhaps 15 minutes. Got the belt at AutoZone for around $10 that was an exact replacement made by Dayco. Much cheaper than Sierra. By the way, the belt I removed was indeed the ORIGINAL Kiekhaefer belt installed by Sea Ray at the factory 43 years ago! I guess I got my money's worth. It showed some fraying and wear but was none-the-less still intact.

 

[JimS123]

Re: Mercruiser I/O 153 cu Belt Replacement

I replaced mine at 25 years. It still looked fine and my mechanic friend said that the way I keep my boat it would last forever. But for 10 bucks I said what the heck. I like to tinker anyway.