Engine removal

S

Slowboat

New Member
Jun 30, 2019
24
Boat Info
2000 340 sundancer
Engines
7.4 MPI mercruiser/ V drives
I have a 2000 340 sundancer. The exhaust manifolds need to be replaced. The bolts are rusted and cannot be removed by wrench. I plan to drill off the head of the bolt and remove the manifold off the stud. Problem being it seems impossible to drill the two inside manifolds. Therefore I want to remove the engines. My question is can the engine and trans come out at the same time.
 
Slowboat said:
I have a 2000 340 sundancer. The exhaust manifolds need to be replaced. The bolts are rusted and cannot be removed by wrench. I plan to drill off the head of the bolt and remove the manifold off the stud. Problem being it seems impossible to drill the two inside manifolds. Therefore I want to remove the engines. My question is can the engine and trans come out at the same time.
Click to expand...
Engine and trans should be able to come out together but man thats a lot of extra time and expense. Pull the boat pull props and shafts, all the wire harnesses etc

If your already cutting the studs, just drill out the remaining stud and chase a tap down the threads. That should be able to be done in place much cheaper and easier.
 
I don’t know enough about the transmissions and removal with inboards, but I have to remove a lot of studs on generator equipment

Usually if I grind the head off and remove the component, with heat and penetrox I can usually use a stud extractor, pipe wrench or channel locks, and get the studs out without having to drill them out of the casting.
 
I have it with penetrating oil about 10 times over the last two weeks before Used a high end extractor to try and remove them. No go. I do have a right angle drill. As long as the trans and engine can come out together it shouldn’t be too bad. I appreciate your response. I will have to sleep in this a bit long. Maybe it will just go aways. lol
 
Thank you Stray current. I was just going to drill the head of the bolt but grinding maybe a better option considering there is no concern about the manifold. Access to the Center two manifolds still seems to be a challenge.
 
Slowboat said:
Thank you Stray current. I was just going to drill the head of the bolt but grinding maybe a better option considering there is no concern about the manifold. Access to the Center two manifolds still seems to be a challenge.
Click to expand...
That’s going to be difficult no matter what and truly I don’t think popping the heads off would work without pulling the engines anyway if it’s that tight. You’d still have to slide them the length of the bolt
 
Can you break up the manifold in place and get down to those bolts? Drills, hole saws, reciprocating saw, coal chisels and hammers. Just about anything is better than having to pull an engine/trans.
 
ttmott said:
Can you break up the manifold in place and get down to those bolts? Drills, hole saws, reciprocating saw, coal chisels and hammers. Just about anything is better than having to pull an engine/trans.
Click to expand...
Agreed. Are those cast iron manifolds? They should break apart easily with a sledge hammer.
 
370Dancer said:
I have pulled engines 3 times without moving the transmissions. IF you have room to slide the engine forward to disengage the shaft. I also leave the engine mounts untouched.
Click to expand...
Yup but he has a 340.....which you and I can no longer fit into. :rolleyes:

I'm not sure beating on cast iron manifolds is a good idea when the heads and block are also cast iron. I'm okay with slicing off the bolt heads with grinder.....but the sparks do give me pause on a boat whose gas tanks are 12" away. I would definitely take a few steps to limit that with a fire blanket.


BTW what's the update on your boat?
 
PlayDate said:
Yup but he has a 340.....which you and I can no longer fit into. :rolleyes:

I'm not sure beating on cast iron manifolds is a good idea when the heads and block are also cast iron. I'm okay with slicing off the bolt heads with grinder.....but the sparks do give me pause on a boat whose gas tanks are 12" away. I would definitely take a few steps to limit that with a fire blanket.


BTW what's the update on your boat?
Click to expand...
A wet moving blanket over the tank and lines and blowers on is my go to when using a torch or making sparks in the hole. And a fire extinguisher at hand.

I also wouldn’t be too keen on beating on cast-iron attached to the heads!
 
I would get the bolt heads off. Grind or drill.
Then spray liberally.
The manifolds should be able to slide off the “studs” until it hits the other engine.
That should give a large enough gap to use a reciprocating saw or hacksaw to cut the bolts bear the manifold
Leaving enough to get a visegrip or pipe wrench on whats left
 
If you can get the heads off of the bolts you would be in great shape. You can use one of those heaters to heat those studs up to red hot and you should be able to easily get them out with vice grips I don't know how much room you have though
 
Stray Current said:
A wet moving blanket over the tank and lines and blowers on is my go to when using a torch or making sparks in the hole. And a fire extinguisher at hand.

I also wouldn’t be too keen on beating on cast-iron attached to the heads!
Click to expand...
You guys are wimps. Ever hear gas boil? :)

when I was sixteen we restored an old car and had to weld some of the frame. It appears that the gas tank was right there. Heard a boiling sound and bolted. No one ever said we were smart. :)
 
Golfman25 said:
You guys are wimps. Ever hear gas boil? :)

when I was sixteen we restored an old car and had to weld some of the frame. It appears that the gas tank was right there. Heard a boiling sound and bolted. No one ever said we were smart. :)
Click to expand...
Bold mechanics
Old mechanics

but there are very, very few Bold & Old mechanics.
 
Golfman25 said:
You guys are wimps. Ever hear gas boil? :)

when I was sixteen we restored an old car and had to weld some of the frame. It appears that the gas tank was right there. Heard a boiling sound and bolted. No one ever said we were smart. :)
Click to expand...
I’m not going to be bold in a hole I can’t get out of quickly with 90 gallons of gas.

Just like I break out the arc flash ppe working on any live voltages over 240 L-L or anything fused over 10000 AIC rated. You don’t get a redo
 
No you don't get a redo on something like that
 
Mechanics have tools we weekend people do not. The boat we have we got in 2005 we have put 3000 hours on it. I changed the risers 2 times myself. The manifolds were leaking water into the exhaust slightly a year ago. I got the marina to change the manifolds and risers. It took them a long time to get the bolts out but they did. They used a thin, limber, agile apprentice and real tools I did not have. You may want to let a professional change them. He spent a day removing and replacing them. In all it took him 3 days.
 
You must log in or register to reply here.

Forum statistics

Threads
113,223
Messages
1,428,889
Members
61,116
Latest member
Gardnersf
Back
Top