650 merc ressurection

[brussell]

I have a 1972 Bomber bass boat with a 650 Merc with Thunderbolt ignition. It hasn't been cranked in a year and last time it did run, it was rough. Idled and fast idled fine but sputtered when moving. Also, it had some water in the foot. The oil was milky. What should I do before I try and crank it?

 

[briannh1234]

Re: 650 merc ressurection

In the FAQ section there is a thread titled waking a sleeping engine. Start there.

If the oil was milky then you have your first problem. You will need to determine which seal has gone bad and replace it. Diagnosis consists of a pressure tester and a spray bottle of soapy water. Add some air pressure to the lower unit and then spray it with soapy water. Where the soapy water bubbles is where the leak is.

- Brian

 

[brussell]

Re: 650 merc ressurection

I changed the two prop seals a few years ago and dinged one up pretty good. I'm sure that's the prob. Where can I find those seals or even a carb kit. Many websites don't have such old parts.

In the FAQ section there is a thread titled waking a sleeping engine. Start there.

If the oil was milky then you have your first problem. You will need to determine which seal has gone bad and replace it. Diagnosis consists of a pressure tester and a spray bottle of soapy water. Add some air pressure to the lower unit and then spray it with soapy water. Where the soapy water bubbles is where the leak is.

- Brian

 

[Plainsman]

Re: 650 merc ressurection

Maybe here? NOt sure of the part # you need

http://www.iboats.com/mall/index.cg...id=271496&view_id=271496&search_type=category

 

[tashasdaddy]

Re: 650 merc ressurection

oldmercs.com good place for older parts. there are suppoose to be seals(washers on the drain and vent screws, that need to be replaced everytime you change the lower lube.

 

[diaric]

Re: 650 merc ressurection

try here at old mercs http://www.iboats.com/bbboard/bbBoard.cgi?a=redirect;url=http://www.oldmercs.com/196263merc500.htm

 

[SeaKaye12]

Re: 650 merc ressurection

Have you done a compression test?

If I were you I'd do that first...then have a look at the ignition; expensive parts might need replacing there. You might find it all to be in good shape...and therefore worthy of repairing the foot. On the other hand, if it turns out that you have expensive powerhead repairs looming...you might end up wishing that you hadn't spent and more time or money on it.

Thanks for reading, Chuck

 

[akwalker]

Re: 650 merc ressurection

Sierra sells a kit for your (our) lower unit,,,,, just did mine acouple weeks ago. about $40.00 for a seal kit,,,,,,,,