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bobwpe
04-18-2007, 12:20 PM
Hi Everyone,
I thought a good way to restart my 18 project would be to attempt to put the engine in as this is likely to generate all kinds of new and exciting activities. I was right.
This is the situation at present. When I got this boat it was essentially just a hull and deck (1973) but the transom had been rebuilt and the hole was cut. I installed the transom assembly and have hung the engine as in the pictures. The alignment tool is in and I think it is reasonably close to the correct position. The rear mounts are resting on the transom assembly and the bolts can be freely slid in and out. There is some tension in the hoist so the forward mounts are maybe 30% resting on the stringers as shown.
The stringers are 8" high and 23" apart. X dimension measured as the difference between the bottom of the round keel to the floor and the center of the alignment tool and the floor is about 14 1/8".
Most of the standard mounts I've seen on this site appear to be made of aluminum angle bolted to the outside of the stringers facing in. It looks like the only way this would work for me is if the engine mounts were about 20" apart instead of the standard 22".
What am I missing? Any ideas or suggestions would be greatly appreciated.
Thanks

MOP
04-18-2007, 09:14 PM
I have a 22 but a far as mounting they are basically the same, my X is about 2-1/2" higher and my stringers are 7" measured on the inside up!
Like you said 22" is the accepted standard, your stringers are to high you would have to have a much higher X not to have to cut the stringers down or go to custom mounts.

Phil

ghiafreak62
04-18-2007, 09:17 PM
Did you rebuild the stringers?

mrfixxall
04-18-2007, 10:28 PM
what mop said,,my stringers are notched and have a 4"x4'' 8'' long aluminun angle through bolted to the stringer..ythe stringers were knoched approx 2 1/2'' down x 8''...make sure you seal the bolt holes and re glass what you cut out so no moisture gets in the wood..

Rootsy
04-19-2007, 06:42 AM
Same issue with my 66 18... inside of stringers are in the stock location.

When i get to it i'll just remove the motor mounts from the block and redrill the holes further inboard so that the lower mounts clear the stringers. the Bases are just angle iron with a gusset welded in place which will get powdercoated and then thru bolted to the stringers with a backing plate.

bobwpe
04-19-2007, 07:08 AM
Thanks for the great replies! At least now I know I'm not completely crazy. I had been thinking that having a machine shop cut and redrill the mounts that are bolted to the motor would work, but was not sure if it was acceptable to modify factory iron like that. It sounds like this is what you are talking about Rootsy and if you think it's O.K. that's the way I'll go. I am planning on using 4"x4"x1/2" aluminum angle on the inside of the stringers with the motor mount side cut down to 2" wide and 7" long.
I think these stringers are original as there don't appear to be any signs of modification in that area. I just can't figure out what was done originally.
I'm off to yank the beast out now and will report back shortly.
Thanks again for your help.

MOP
04-19-2007, 12:09 PM
Are there holes near the front of the engine? It may have had an H/M setup in it at one time, if you don't feature cutting the stringers down which should be fine you could use and offshore front mount. Though it may be more of a hassle with the serpentine brackets not sure.

Phil

bobwpe
04-19-2007, 02:40 PM
Thanks MOP,
I don't believe there is another location on the engine block for the mounts if thats what you mean. In any event, I brought the mounts to the machine shop this morning to have them cut back and re-drilled. Then I'll put it all back together with the angle bolted to the stringers to get an exact location for the mounts that attach to the angle. Right now it looks like the angle will have to be bolted to the inside of the stringers rather than notched because there is a gusset in the way on the outside of the stringer. FWIW, the parts boat this engine came out of had the stringers at about 31" and the engine mount angle was bolted to the inside of the stringers.

MOP
04-19-2007, 04:06 PM
You may have to cut a bit off the tops of the adjusting bolts to be able to get your box wrench in.

Phil

mrfixxall
04-19-2007, 05:44 PM
BTW your going to need a set of thease to mount the castiron motor mounts to the angled alunimum you bolt to the stringers....thease are solid mounts for racing,i reccomend getting a set of mounts from merc....They have rubber issullators in then and can take a shock when airborn..

bobwpe
04-28-2007, 03:21 PM
Hi Again,
I got the parts back yesterday and it didn't take long for the following issues du jour to pop up:
The mounts end up at the very front edge of the 8" long angle which I had to move aft of it's ideal location to accomodate a gusset. I thought it would end up with the angle extending about 1" beyond the mounts but I was obviously wrong. Does anyone think I should go to 10" long angle or is what I have strong enough?
With the mounts up against the stringer on either side, the engine mount posts are 20" apart while my re-configured mount brackets end up just under 20" apart which would be perfect.................except the centerline of the crankshaft favors the stbd. stringer by about 1/4". I think the best solution is to eat a new mount bracket for that side and have it cut 1/4" deeper (there's room). I tried to find the engine mounts Mrfixxal described but all my Mercruiser dealer has is the same thing I have but in aluminum. If they were narrow enough, it would solve my problem but they would have to be 1/2" narrower and it doesn't look like they are.
Any comments or suggestions are welcome.
Thanks to everyone who's contributed to this and the hundreds of threads I have read and re-read to get to this point. It really makes this project a lot more enjoyable.

MOP
04-28-2007, 04:02 PM
Have you read this thread, I tried to give a fair explanation of setting up the engine mounts, it may help with your thoughts. I would hang the engine to make sure where it has to be for good alignment then do what ever is needed to get it done right.

Phil

http://www.donzi.net/forums/showthread.php?t=33750&highlight=alignment

bobwpe
04-28-2007, 04:20 PM
I read that thread as well as a few others of yours to get to this point and believe me I appreciate the help. The engine mount in the picture is very close to where it will end up based on where it was in the pictures in the beginning of this thread, only moved inboard 1". I justed wanted to know if it's O.K. to place the mounts at the front of the angle. Once I know if I can do that, I will re-hang the engine and use your procedure to find the exact location to drill the engine mount holes into the angle.
Thanks

MOP
04-28-2007, 04:31 PM
I would like to see it centered but I think it will work out fine, the big thing is smooth and easy tool insertion! Gee I think she said that once:wink:

bobwpe
05-05-2007, 10:47 AM
I decided to go with new 10" long angle as I had only drilled two holes at that point and I was able to re-use one. I'm sure it would have been O.K. with the 8" long angle but it seemed a bit marginal and now seemed like the time to make the change rather than wish I had later.
The local Mercruiser dealer had a used mount bracket for the stbd. side that I was able to get for $30.00 vs. $138.00 for a new one. I had it cut back and drilled 1/4" further in than the first one and now everything fits perfectly. The alignment tool moves in and out freely and the side to side alignment seems just right. As you can see from the photos, there is about 1/16" on the outboard side of the mounts so this can be adjusted slightly if it becomes necessary.
Now I just have to take it all apart and have the motor mount holes drilled. That's one more "issue" resolved thanks to the fine and freindly folks at Donzi.Net!

MOP
05-06-2007, 08:14 AM
Have you tried inserting the alignment tool yet to get an idea of how close you are?

bobwpe
05-06-2007, 10:53 AM
I've gotten quite friendly with the alignment tool over the past two weeks. I adjusted it to where the tool had the loosest fit, then moved the mount nuts up and down to get slightly out of alignment and back to the fit where there are no marks on the grease to be sure I was at center. I then loosened everything up and raised the engine completely loose and set it back down again and repeated the above just to be sure. I got the side to side alignment at the beginning which is where all the mount bracket modifications came in.

mrfixxall
05-06-2007, 12:49 PM
I've gotten quite friendly with the alignment tool over the past two weeks. I adjusted it to where the tool had the loosest fit, then moved the mount nuts up and down to get slightly out of alignment and back to the fit where there are no marks on the grease to be sure I was at center. I then loosened everything up and raised the engine completely loose and set it back down again and repeated the above just to be sure. I got the side to side alignment at the beginning which is where all the mount bracket modifications came in.

After you get everything bolted in place check the aleignment,pull out the tool then rotate the motor 90 deg and check it again,then another 90 deg and check it again....do this to make sure the aleignment is rite on through out the whole revalution of the engine...Those mounts can be found at eddiemarine.com....

good luck.