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Engine mounting bolts are loose
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Engine mounting bolts are loose
I have an 1957 Capri (19') with a KFL 131 hp engine in it. I noticed that the mounting bolts that attach the engine to the frame are loose. I tried to tighten them up, but it appears that they are stripped. There doesn't appear to be any wood rot on the frames so I think that years of vibration just wore the wood out. Short of replacing the frame I was thinking of drilling out the bolt hole, epoxying in a substantial size dowel rod and then re-attaching the bolt. Think this will work? Any other ideas?
Thanks much!
Thanks much!
- Jim Godlewski
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Re: Engine mounting bolts are loose
Works well....solopar wrote:I have an 1957 Capri (19') with a KFL 131 hp engine in it. I noticed that the mounting bolts that attach the engine to the frame are loose. I tried to tighten them up, but it appears that they are stripped. There doesn't appear to be any wood rot on the frames so I think that years of vibration just wore the wood out. Short of replacing the frame I was thinking of drilling out the bolt hole, epoxying in a substantial size dowel rod and then re-attaching the bolt. Think this will work? Any other ideas?
Thanks much!
- steve bunda
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Bolts
Hi Solo, I think you are asking about the square head lag bolts that fasten the engine mounts to the stingers.The dowel method is good for badly worn out holes, engine replacement and wood rot, but sometimes a couple of mahogany wood splinters dropped down the hole with a little glue can firm up the lag.
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Are the lags bronze? Steel lags tend to rust and effect the surrounding wood when moisture is present. See if you can get bronze ones another inch longer, or better yet one diameter larger if they will go through the mount. Blow the hole out with air gun, ensure the hole is dry, then run the bolt in to ensure fit and ability to tighten (not overtighten). Remove the bolt, blow out hole again, then reinstall with a dab of 5200. Just a dab to act as a thread locker. If you have to go longer, drilling a healthy sringer will be neccessary. Just one man's idea. CQ
It is the square headed lag bolts that attach the engine to the stringers. I'm not sure if they are steel or bronze, but I'll replace with bronze. It sounds like using a lag bolt an inch longer and perhaps a size bigger might do the trick (adding a Mahogany splinter and either 5200 or West epoxy as a thread lock). I'll let you know how it turns out when I get it finished. Thanks for the advice!
- Pete DeVito
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Solo,
Always a good idea to plug the holes and redrill just as you decribed. I have pulled engines out of some of my boats and over time the lag bolts will not hold as they should. Get your dowel and then drill the hole to fit the dowel and glue it in and let it set. Set your engine correctly to the coupling and then redrill your holes. If engine stringer is in good condition no need for any major work..
I own a 1957 Capri and the photo below is the correct square headed lag bolts for your model you should have two sizes.
Pete
Always a good idea to plug the holes and redrill just as you decribed. I have pulled engines out of some of my boats and over time the lag bolts will not hold as they should. Get your dowel and then drill the hole to fit the dowel and glue it in and let it set. Set your engine correctly to the coupling and then redrill your holes. If engine stringer is in good condition no need for any major work..
I own a 1957 Capri and the photo below is the correct square headed lag bolts for your model you should have two sizes.
Pete
Past Project 1948 17' Deluxe
Past Project 1957 19' Capri
Future Project 1955 17' Special Sportsman
Past Project 1957 19' Capri
Future Project 1955 17' Special Sportsman
Doweling Holes
If you use a dowel, the lag bolts threads will be pulling with the grain of the dowel and does not hold as well. I took a 3/4" oak board and a 1" hole saw on a drill press and drilled out 4 plugs for each hole. You have a pilot hole in these so I ran a 1/4" all thread rod and glued each piece together and then removed rod after glue dried. Drill out your motor mount holes to 1" and glue these plugs in the hole. You now have a pilot hole for the correct bit sizing for the lag bolt. I used Gorellia Glue for gluing because it expands. You can make the plugs longer or shorter by adding/subtracting plugs. Now you are pulling against the grain.
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Re: Engine mounting bolts are loose
I just noticed this post, funny as shit! We used to make fun of my dad for fixing everything with a hammer, can of wd40 and a roll of duct tape:) I guess I should have listened to his advice earlier in life!
Re: Engine mounting bolts are loose
Be sure your engine mounts to the stringers are strong, whatever method of fix you use. The full thrust of the propeller is transferred to your boat at these joints. At high speed the thrust can be over 2000 pounds. If your engine mounts are not of high integrity the engine can twist on the stringers causing vibration or worse.
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