Need Advice

[88Sunbird4.3L]

Ok. So here is my situation. I purchased an 88 Sunbird w/ an omc 4.3l. When I got the boat the engine was completely seized, and when i pulled the motor apart there was water in the pan and the cylinders where totally rusted. The guy I got the boat from said he was running it, all of a sudden it died and he found water in the pan.. so he parked it for a while.. then sold it to me.

I just mounted a new motor, and have yet to bolt up manifolds to start it for the first time, but was wondering if anyone could tell me what could have possibly caused the engine to fill with water. My concern is that it was the manifolds which are the one piece ones. I would like to use the old ones that came on the motor, as I cant afford new ones right now. Could these manifolds have been the cause of the motor filling with water? I really dont know what to do, I really want to start my boat so I can iron out the kinks, but am afraid of blowing this one up too (its a fresh crate motor). Thanks for the advice!

 

[Fishermark]

Re: Need Advice

While I am not familiar with OMC... the manifolds are the most common cause of water injestion. I certainly would not reuse the old ones without checking them out thoroughly.

 

[88Sunbird4.3L]

Re: Need Advice

What would be the best way to test these manifolds? Would a marine mechanic be able to check them out?

 

[HT32BSX115]

Re: Need Advice

You know,

You spent a LOT of money on that new engine.

A new manifold riser kit is around $500. I would not put old risers and manifolds on a new engine. http://www.ebasicpower.com/exhaust/omcex.php

 

[88Sunbird4.3L]

Re: Need Advice

You know,

You spend a LOT of money on that new engine.

A new manifold riser kit is around $500. I would not put old risers and manifolds on a new engine. http://www.ebasicpower.com/exhaust/omcex.php

If it were $500.. Id do it.. but I need the one below that on your link.. for the 4.3L.. the one that replaces the one piece manifold,, they are $1000.. thats my biggest problem

 

[HT32BSX115]

Re: Need Advice

I understand that problem.

But here's your problem right now. You have manifolds and risers that MAY have caused the previous engine's destruction or may cause the new engine's destruction.

Manifolds and risers have a service life. It's more a chronological time instead of an engine time......I.E they rust when you're not using the boat. So they may have low hours on them but still be ready to start leaking. You cannot tell when they WILL start leaking. So a "mechanic checking them out" may only be able to tell you they aren't leaking "today"......

If they start leaking right after you lay up the boat for winter, you may end up with water sitting on top of pistons (where the exhaust valves were open when you shut it down) that will sit there all winter etc. Next Spring, you find out. Then you pull the engine....(again)

 

[88Sunbird4.3L]

Re: Need Advice

Ok.. well I guess I have no choice but to get the manifolds by the responces thus far. I will start saving today. Thanks for all the info.

 

[mcleaves]

Re: Need Advice

HT32BSX115 is right.. These are wearable parts.. I wouldn't re-use them any more than I would reuse the old oil .

It's like a water pump impeller or ujoint bellows. Some people risk running them well past their recommended usage, and they will have anecdotal stories about how they never changed them in 20 years. But for every one that dodges the bullet you local marine shop has a bunch that didn't. In your case you have just a few items that could have driven water into the engine, and the manifolds and risers are a good suspect.

If it were me I'd be replacing them. It's not like other parts that if you use the old one nothing gets damaged but your pride when a starter or alternator fails.

M