Replacing manifolds on a 1800SR3 2006 Mercruiser v6 4.3ltr

[Andy_]

Hi,

I'm looking at replacing the manifolds due to corrosion and the water dripping onto the engine mount, on the left side.

How would I go on replacing the engine mount that is corroded?

Is this a difficult job or just time consuming due to the limited space in the engine bay?
Is is also better to replace the manifold and elbow all at once?



Thanks
Andy

[mmwjr]

The mount is two parts, one is the iron bracket that is bolted to the engine block and the other which is the true mount is lag bolted to the stringer and has a stud the goes through the bracket on the engine. The bracket can be cleaned up and reused but you’ll probably have to cut the rusted nut off. I would try spraying it with PB Blaster the heat the nut with a torch and finally use an impact wrench to see if you can get the nut off. Note once the mount is replaced the outdrive should be removed to check/adjust engine alignment else you can have premature failure of the engine coupler. I replace the exhaust manifold and elbow/riser. Note these are Mercruiser’s dry joint design but you can find aftermarket ones if you want to save a few dollars, however the aftermarket ones typically aren’t painted.

[Andy_]

Thanks Mike.

I'm guessing that to completely remove the engine mount could be a misson. Do you think it would be possible to drill out the bolts that go into the stringer for the one in the picture? Don't really want to take engine out.

Andrew

[mmwjr]

I would try using a socket on the string bolt before drilling it out which would be the last thing to attempt. If you can get a socket to work try a large vice-grip. It’s a lag bolt that screws into the wood of the stringer. Drilling should not be required IMO.

[shrew]

I'd pull the engine. It's not as hard as it sounds. I've done two 350's, a 7.4 and an 8.1. Take the time to paint the engine compartment and get into anything else that needs attention while you're in there. You'll need an A-frame and a chain fall.

[mmwjr]

Originally Posted by shrew

I'd pull the engine. It's not as hard as it sounds. I've done two 350's, a 7.4 and an 8.1. Take the time to paint the engine compartment and get into anything else that needs attention while you're in there. You'll need an A-frame and a chain fall.

He’ll need to remove the lag bolts to pull the engine anyway, or undo the mount from the engine. But eventually remove the lag bolts. But yes pulling the engine isn’t that hard if he has a way to lift it.