Our 1984 Yanmar has been shaking for years, but doing well. Replaced engine mounts (for the first time), but engine still shook. Other posts suggested transmission cone, algae on the prop, etc. Fortunately (or not) the engine refused to start. Got a real mechanic to look at the engine. After some work he found 2 of the 3 fuel injectors were bad and the after a compression test 2 of the 3 cylinders were bad and the third was worse. Unfortunately mystery solved. 1984 engine needs a 2021 overhaul -- yuck!
3gmf engine shake
- Thread starter Mike Oldak
- Start date
Don't know how much of a gearhead you are, Mike but this file has some info on sourcing parts through the tractor parts network..This is for the 3 GM and 3 GMF engines. I am not recommending these guys or recommending going to the tractor network, just offering it as info for your perusal.
Yanmar Tractor Engine
YM2002_2002D: Yanmar Tractor Parts
http://www.stevenstractor.com/parts/compacts/yanmar.html?limit=all&cat=1521
The 72mm bore engines are on Yanmar tractor models 169, 180, 186. 187, 1401, 1502, 1510, F 14, F 15.
Yanmar Tractor Engine
YM2002_2002D: Yanmar Tractor Parts
http://www.stevenstractor.com/parts/compacts/yanmar.html?limit=all&cat=1521
The 72mm bore engines are on Yanmar tractor models 169, 180, 186. 187, 1401, 1502, 1510, F 14, F 15.
Mike, how did you go about changing your mounts? Use the boom for the lift or a board across the companionway? Sorry to hear about the cylinders, I fear mine may be on a similar course as yours after years of little maintenance from previous owners.
THANKS for the site! I know Yanmar parts are a bit hard to come by at times, especially right now. While I've built about 10 gas engines for race cars, etc. I'm going to let our very competent mechanic do the major part of the rebuild since he knows the local machine shops etc. I may just pull the head. While there are 4 owners, we've been doing major restoration on the boat over the last 2 years and just paid for a new Harken roller reefer and two new North Sails, so we're going to see if we can get away with having the injectors rebuilt and see if that will work for another season and if not I'll pull the head and we'll get the valves replaced. Otherwise, its a restoration of all the internals, leaving the outside parts on an as needed basis. This way we might get another season out of the engine and spread out the costs.
I watched our mechanic do it. First he got some 4x4x 2 foot long pieces of lumber and pushed them into the engine bay touching the engine angle iron. Then unbolting the engine mounts (and other hoses, wires, etc.) from the angle iron, he slid the engine onto the 4x4s and out of the engine bay. After 30+ years the bolts holding the angle iron were wobbling a bit, so I drilled out existing holes to 3/4 inch keeping track of the the location of the original holes by horizontal and vertical lines. I then back filled them with Thiox thickened epoxy and put some heavy tape over the hole. See picture below
I did this when it was winter and tried to use a standard tube gun, but the Thiox was so hard I had to put it in front of a heater to get it more usable. Apparently there are 8:1 guns that would have been very nice) I then re-drilled the holes for the 3/8 (?) inch bolts.
Some of the bolts on the port side go thru with nuts hidden behind the wall in the aft compartment. I had to cut a 6" wide piece in the bottom of the wall, but will reattach it and put a molding strip over the prior saw line. I also added some of that white seaboard(?) under each motor mount to provide some additional height which was needed. See picture.
While the engine was out of the bay, I cleaned it and applied a new coat of Yanmar paint.
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Mike thank you for the detailed reply on that! I will having to do the exact same thing soon. Hopefully next fall if I can baby it enough this season while I finish out my vbirth and main salon.