5.0 L yems

[Watterbug]

I have a 92 Kayot with 5.0 L yems. My block is cracked and I have to do a motor swap. I can't find any service manuals for it. I have changed several auto motors but never a boat. I'm just not sure what is behind the motor that I can't see, do I need to remove outdrive, and so on. I would also need to know specs for motor. I know it's a Chevy 305 but a marine engine is different. Any way, any help with a manual would be appreciated.

 

[alldodge]

Howdy
Sorry but I have not heard of "yems"

If you have a GM 305 (5.0L) then any marine 5.0 long block can be used to replace

 

[Watterbug]

Acronym. Definition. YEMS. Yamaha Engine Management System. Copyright 1988-2018 AcronymFinder.com, All rights reserved.
Sorry for the confusion. I was trying to be brief. I have a Yamaha stern drive. I have a 305 bare block that I am going to build myself. The block is in the right year range to match the one I will be replacing. I want to know the exact steps of separating the outdrive from the power plant. What parts I need to mate them back together. As for the engine. What type of cam in terms of lift and duration. Roller. Pushrods. Lifters. Timing chain and gears. What type of crankshaft. Standard. Heavy duty. Bearings. Block. 2 bolt main bearing caps or 4 bolt main bearing caps. You know. The specifications that make it a marine engine. And so on and so forth. I am trying to find a manual that will tell me this if one exist for the Yamaha outdrive. Any bit of information or advice would be greatly appreciated. A manual can tell me what to do and what not to do as not to waste time.

 

[alldodge]

OK thanks
There isn't many folks which have a lot of knowledge of the drive and I'm lacking also. Hope someone with more info comes along.

The drive will slide off once the trim cylinders are removed and drive is unbolted. The motor is a standard GM 305 Truck motor. It needs to be a truck motor because of the cam, and more low en torque. After that it needs brass or stainless steel core plugs and a marine head gasket.

The water circulating pump is also marine and not a standard auto type. Alternator, starter, distributor, carb are all marine and everything else is just regular GM and most machine shops can do the work

 

[castrolina]

Yes sir, pull the drive, remove wiring harness. fuel lines, etc. I removed risers, elbows, and manifolds for less weight, and had to remove distributor for clearance, engine mounts. The shop manuals are on ebay. I used a car engine puller and it was a pain in the rear, use a hoist if possible to lift forward and up. I did a head gasket repair and y-pipe gasket, but logged every wire and bolt then used the book for reference. Not sure of internal engine specs, those will be in the manual. good luck.

 

[Watterbug]

Thanks castrolina. Big help.