Motor bearing going bad?

[dafirstboat]

Hello All,<br /><br />I'm a complete first timer to the forum as well as the boating world, just so every one knows in case I say something stupid. Anyway, on to my problem with the boat.<br /><br />Last summer I bought a 1981 Thompson with a Mercruiser 120 and alhpa1 out drive. The guy had an issue with the distributor, (the stator screw came lose and pretty much tore the thing off) anyway he replaced the parts and couldn't get it running so there it sat for a couple years. I bought it pretty cheap thinking I might be able to get it running, I was able to by cap and plugs and set the timing and BAM the thing fired. So to the lake I went. I took it slow for a while but then started to speed up the thing seemed to get pretty hot and smoke but with 2 years of storage I kind of figured it was that, then it started to squeal and higher RPM's but would stop when I backed it down. So back to the trailer and into the garage for some more tinkering. I thought maybe it might have just been the alternator belt since it was stretched pretty good and a little loose. I replaced it, changed the oil and filter (which was very thin, I think with gas) and back to the lake. This time I stayed at the dock for quite some time until it was good and warm and once it warmed up the squeal came back only now it was also doing it at idle. Since I was at the dock with a buddy I was able to get back to the engine and try to see where the sound was coming from, it sounded to be coming from the very back of the motor but was not able to figure out exactly where it was. I'm afraid this is a main bearing or something and the engine will need to be rebuilt, something I'm willing to do if that’s the problem. Also I don't know if this is matters or not but when I changed the plugs the outside of the front plug was pretty rusted around the base, the threads and what not seemed fine but there was rust on the plug, not sure if this is a normal thing or not or even if it has anything to do with the squeal just trying to give as much info as possible.<br /><br />But that’s about the story, any suggestion would be greatly appreciated. Even if it is just a suggestion on how I can check it out to know it’s the bearing or something else for sure before tearing it all down.<br /><br />Again hope this isn’t to long or winded just trying to get as much info in the first post as possible.

 

[tommays]

Re: Motor bearing going bad?

da<br />i think the simple thing to do would be to pull the outdrive and run the motor without it for 20 or 30 seconds and see how things sound<br /><br />theres a lot of things in the outdrive like the gimble bearing that can make bad sounds and this will help decide if its your motor or drive<br /><br />if you need to run it longer you will have to hook up a water hose to the motor or it will get to hot<br /><br />tommays

 

[Don S]

Re: Motor bearing going bad?

Sounds to me like you have several problems there. The overheat is probably from lack of water. After sitting that long the impeller is probably shot, and could also have made the squeeling sound. With a lack of water flowing, you could have burned the exhaust hoses (the Smoke) Some of the squeeling and smoke may have come fromt the engine coupler itself if it's damaged.<br />You really do need to pull the drive, change the water pump impeller (and possibly the housing) and check the ujoints and gimbal bearing. They could also be rusty if the bellows had water in it.<br />You need a service manual big time.<br />Here's a site with some useful information also.<br /><br /> Mercstuff

 

[trog100]

Re: Motor bearing going bad?

main bearing dont sqeal.. they kinda rumble and cause vibration under load.. also u would have low oil pressure.. its probably something attached to the engine not the engine itself thats making the noise.. tommays idea is a good one..<br /><br />trog100

 

[Richard Petersen]

Re: Motor bearing going bad?

I remember how a "stuck in all the time" starter motor sounds.

 

[bigbrownbuku]

Re: Motor bearing going bad?

definately remove the outdrive and service it. while it is off shine a flashlight thru the gimbal and check the "donut" splines for wear and the gimbal also check the donut for any signs of breakdown ie: pieces of rubber. while the leg is off you can run the engine with a hose attached to the cooling hose inside the boat.