Pulling Mercruiser 165 with mounts or without?

[ethan169]

Ok So I have a 1981 Glastron SSV-177 with the Mercruiser 165 I6, or gm 250.... I have never had this boat running. I bought it as a project with very little information except that it seems to have very few hours. Less then 100 according to the hour meter.

I have low compression on a few of the cylinders and I pulled the head to check on things. I searched all around and cant see any cracks in the block or head. Manifold seem ok too. I drained what it had for oil and there was water in there. Also two of the combustion chambers looked quite dirty. My guess is water was sitting in there for some time. Not sure how long though.

Anyway I plan on pulling the block from the Glastron in the next few days. Even if the block is good it will need to go to the machine shop. My question is weather or not I should un bolt the engine mounts from the bilge rails or should I leave the mounts and unbolt the engine from the mounts? I know alot of people pull them with the mounts so they don't have to do an engine alignment. The FSM also states this. What do you think? how hard is it to do an alignment? I mean ive read the procedure and I can either purchase the tool or create one (have a lathe at work and plenty of material) but if its a major PIA and I can avoid it then why not?

Thoughts?

Thanks for any advice!

 

[ethan169]

 

[Bondo]

I know alot of people pull them with the mounts so they don't have to do an engine alignment.

Ayuh,..... If ya pull the motor, an alignment needs to be done,.... Don't matter whether the mounts go, or not,.... Ya leave the mounts on the motor, so's ya can Block it on the Floor,....

 

[Sangster21]

What sort of cooling system do you run? It looks like water has gotten to cylinders 5/6. I think water back to #6 can indicate a bad gasket between the manifold and riser. The exhaust side of manifold fills with water and if ex valve is open on shut down water can get into cylinder past exhaust valve.

 

[achris]

What sort of cooling system do you run? It looks like water has gotten to cylinders 5/6. I think water back to #6 can indicate a bad gasket between the manifold and riser. The exhaust side of manifold fills with water and if ex valve is open on shut down water can get into cylinder past exhaust valve.

As it has a long water hose (between transom and front of engine) and we don't see a heat exchanger of fittings for one, I'd guess it would be sea water cooled... Water in cylinders from the exhaust side could be the elbow gasket, but is more likely the elbow itself. The old style elbows have a life of about 5-7 years in salt... After that, they corrode at the top and drop water straight back into the manifold....

Chris......

 

[ethan169]

Bondo this technique of keeping the mounts on the block to avoid realignment was taken from the factory service manual. But after some thought I agree that it should be realigned or at least checked when put back in. Chris is correct it is raw water cooled. As I mentioned this is how I got the boat so I don't know much about what happened. I will check the elbow though. It seems reasonable. Do you think it will be a big deal to freshen up the block? I assume I would need new components. I guess maybe I need to pull the block and see how the lower end looks first. Thanks for the responses guys!

 

[Will Fish]

If you are going to pull the motor, I would definately leave the mount in place and pull the motor from the mount. You do not want to strip or damage the wood in the stringers by pulling the mount out. You will need to do an alignment regardless.

As for the water, I would agree to start with the riser/elbow and the manifold. Both life expectancies are 5-7 years in the salt. Since you do not know the history and water has been sitting in the block, I would also recoomend going over the entire block. IMHO the inline 250 is definately worth keeping as its a work horse and fairly easy motor to work on.

 

[Bondo]

If you are going to pull the motor, I would definately leave the mount in place and pull the motor from the mount. You do not want to strip or damage the wood in the stringers by pulling the mount out. You will need to do an alignment regardless.

As for the water, I would agree to start with the riser/elbow and the manifold. Both life expectancies are 5-7 years in the salt. Since you do not know the history and water has been sitting in the block, I would also recoomend going over the entire block. IMHO the inline 250 is definately worth keeping as its a work horse and fairly easy motor to work on.

Ayuh,..... Actually, that's 1 more reason to leave the mounts on the motor,...
If the stringers are Rotten, it's better to find out, as yer takin' the motor Out,.....
Not later, runnin' across the pond,....

 

[ethan169]

Thanks for all the help guys. I ended up leaving the mounts in for now. I didnt realize that the rear mount on the I6 is really just the bellhousing mounted to the transom assembly. I dont see how you could remove the engine another way if you wanted to. Or at least not with a ton of extra work messing around with little bolts in tight spaces.

The whole shabang came out quite easily which was nice!