3.0L to 4.3L mtr mounts and 25 yo transom

[Rick Stephens]

Might be a good treatment to go up the transom drill out inject at the corner. (? - I don't know the proper word describing the corner where the bottom turns into side hull) Since any water intrusion from the transducer/speedo/tabs will travel down the base of the transom to the keel, injecting glycol at the corners should travel that same path.

 

[alldodge]

If you can get it injected a kill all the spores you should be good. Guess the issue is if you can get it to every location

 

[Rick Stephens]

If you can get it injected a kill all the spores you should be good. Guess the issue is if you can get it to every location

Agreed, and don't know a thing. Guess one has to try. I did order a moisture gauge. They are reasonable enough and useful in other things.

Once I get all the paint off, I probably will give the majority of the transom a coat of resin on CSM so seal it off. Seems a better choice than just the resin.

Thanks gentlemen.

Rick

 

[Watermann]

I love to see motor upgrades, could you post a pic of the boat overall?

Also Rick if you want it I have a PDF that shows every possible measurement of the MC 4.3L engine which came in handy for me when I did my upgrade. Saves having to measure and go back and forth. Send me a PM with an email address and I will send it to you.

 

[Rick Stephens]

No Title

Watermann,

I'll send the PM. It will help a lot to have drawings. PM on the way. I been doing my doghouse measurements by installing the Y pipe and the risers

Boat is not very big. Should be a lot of fun to add some go to it. Motor is currently in machine shop getting brand new cylinders punched out AGAIN as the previous owner, who bought the boat as a fixer upper with a brand new Vortec engine, and which I bought as a donor boat, said PO left the flame arrestor off the cab and just tossed a cover over it outdoors in washington state. Needless to say, cylinder #6 is badly pitted, with brand spanking shiny new pistons, rings and everything. So it gets another set of brand new shiny oversize pistons and rings.

Rick

 

[Rick Stephens]

No Title

Don't like lag bolts, would use thru bolts, maybe with aluminum angle plate. Using thru bolts then install engine mounts on the plate with slots in the plate to allow some side movement for ease of installation

Alright AD, I have been grinding out the paint and gelcoat down to the laminating glass in the bilge, the transom, and up over the stringers. Thinking about your metal plate motor mounts as opposed to using lag bolts into laminated plywood mounts.

I'm a welder. Been in the welding/fabricating business most of my life, so this is attractive to me. Since I need around 4 inches of lift above existing stringers, I could easily make up most of that by fabbing up aluminum risers.

Question then becomes - how do you attach said aluminum mounts to the stringers? Can they be glassed in? I've never seen that done, so I didn't know the rules. Or do I need to lag bolt them to the stringers?

Appreciate the thoughts.

Rick

 

[alldodge]

The bolts go completely thru the stringers. Glass and cloth is laid and finished, If necessary sand the one side area where the aluminum 3 inch angle sits against the stringer. Then drill thru the aluminum angle and stringer. Use sealant in holes and put bolts clear thru and secure on the other side.

 

[Rick Stephens]

No Title

I got ya. So you chop a hole in the floor and access the other side. Put a plate on the outside under the floor, run bolts through the mounts on the other side and secure. Patch the hole in the floor. I've been laminating my 3 and 3/4 inch high plywood mounts. Not sure really how I want to complete this..... Welding up some mounts would not be very hard. Tough part is the fit. I think it would have to be pretty long so the center could be left open to access the motor mount bolts. Means bigger hole in the floor.


The transom is original wood. You can see the dark staining of the bottom half with the dust vacuumed off. My intention is to CSM the area that is sanded off and wrap the keyhole, which is all sanded out as well. Wood looks great in the keyhole, Dark stains are dry and layers are solid. I'm pretty comfortable with wood quality.

 

[Rick Stephens]

I drew that off. The center of the bolts for the engine side mounts are straight over the inside edge of the stringers. So I could glass in a 1" piece to widen the stringer and then go straight up and over with the angle at the top at least 2.5 inches from the floor. Should be plenty to get nuts and washers in there.

 

[alldodge]

I see there is more of an issue here, what about this method. Bolt can be raised up some also

 

[Rick Stephens]

No Title

Well, my first drawing was off in showing the bolts for the mount being in the middle of the stringer. Those bolts are literally lined up directly over the inside edge of the stringer - I believe at 18.5 inches apart, and the stringers are 18 inches between them. So I wouldn't want to cantilever the mount off the outside of the stringer - better to build up the inside and move further inboard.

Haven't decided yet wether to build something like this or just laminate in mounts and lag it on. Nice thing is with this method is the glassed in mounts are separate and isolated from the stringers as a source of water contamination.

 

[Rick Stephens]

Digital moisture meter showed up. I got the type with the sharp contacts sticking out that you stab the wood with. Definitely repeatable readings when moving back and forth.

The transom itself is all over the map.. Several year old stack of dry AC plywood in the shop is 8-10%. Several year old fir 2x4 from a stack of new wood in the shop, but now leaning against the porch where a little rain fell on it last week is in the 18-20% range. On the boat the wood around the bolt holes in the transom cutout area is 18-21%. The transom 8 inches up the starboard side is 31%. Lower down is mid teens to 25%. The transom up high is 8-10%. Highest I saw in transom was mid 30's. I expected bottom inch or so to be really high, but it wasn't as high (mid 20's) as the 30-35 up about 8 inches and off to the starboard side of the cutout by 8 or 10 inches.

 

[Bondo]

Haven't decided yet wether to build something like this or just laminate in mounts and lag it on. Nice thing is with this method is the glassed in mounts are separate and isolated from the stringers as a source of water contamination.

Ayuh,.... While I'm also a welder fabricator kinda guy, Lookin' at yer drawin's, it looks like the laminated blocks, 'n lag bolts is a better fit than fabin' up aluminum mounts to me,....
Especially seein' ya gotta cut holes in the deck to put nuts on the bolts,...

Did you find the point in space the way I described in that other thread,..??
Hangin' the motor, 'n alignin' it,..??

I've done metal mounts in some "Off-shore" type boats, 'n they ain't all that great, compared to plywood blocks,...

The Best tip I can think of is, don't over do it, as the bigger the mounts, the more they'll be in yer way someday,...
The 1st time I pulled the motor in my tinbarge, I skeletonized the aluminum mounts I'd made previously, as they were in the way, All the time,...
I cut out 'bout 1/2 of 'em, 'n now I can reach 'bout everything, with the motor in-place,...
Oh, Btw, the aluminum plates only bring the grade up to the deck, there's 3" plywood blocks on them, the motor's mounts are lagged into,...

'n no disrespect to AD, but 99% of the boats out there have their motors held down with lag bolts,......
Mine included, over 15 years, goin' on 20 now,....

 

[Rick Stephens]

Thanks for the thoughts Bondo. My boat is stored inside my shop and I'm totally anal about putting the cover on when out on a trip and it rains. Glassed in mounts would outlast my age bracket by those standards.

I appreciate the properness and elegance of aluminum mounts, and I just had to consider them. But it will take at least twice as much work to make em up and attach them. And it has the same weakness as lag bolts only lower down, a bolt in a stringer is a bolt in a stringer and a source for water intrusion.

I don't currently have the engine block to do your measurement method, it is off getting some machine work.. However, I have the nearly identical boat that was the donor for the motor and drive sitting here to measure off of. I installed the transom plate in the donor boat yesterday to triple check all my mount dimensions, and then reinstalled in my boat to triple check there. Makes it really easy to reverse engineer to just duplicate what Bluewater did. The hulls themselves are identical, the later built donor boat was considered 2 foot longer - but the hull isn't any longer, they just added a new style platform tail on the stern instead of the squared off stern my boat has. I'll shoot a couple stringer/motor mount comparison pics later today to show what I'm planning. I want my mounts to be at most 8 inches on top. I may angle out to a longer base where it gets glassed to the existing stringers. Simple is usually best though.

Thanks kindly for everyone's thoughts. I have spent considerable thinking time considering them and weighing out the alternatives. Lots of ways to skin this cat.

Rick

 

[alldodge]

'n no disrespect to AD, but 99% of the boats out there have their motors held down with lag bolts,......

None taken Bondo, the industry does more lag bolts then anything else (cheap and easy IMO), just seen why to many of them rot out for water seeping in over time. Have never seen a thru bolt rot out from the bolts, if it does happen it was because something else was leaking.

The easiest answer is to use blocks and lag bolts, so if you do a better job then the original builder they should last longer

 

[Rick Stephens]

Thanks AD. You have no idea how awesome it has been to run ideas back and forth through you and the others. I really like the idea of metal mounts. It hits me right in my 'do it right' zone. I think it is justified to cut the workload down and do lags on laminated mounts. I tell you what - a couple layers of 1708 spread up and down the stringers is going to be enormously strong. And as noted, if I 5200 the lag bolts in they aren't going to leak. Hopefully I never have water up to that level - that'd be above the floor

Pictures soon.

 

[Woodonglass]

As I stated previously, and as Bondo has stated, almost all of the MFG's lag bolt the Motors to the mounts. Yeah it's prolly due to cost factors but...IF you do it correctly and pre-drill the holes AND then coat the bolts and the holes with the appropriate sealants, and then do the proper maintenance and upkeep on the boat there's absolutely no reason for them to ever take on water or fail. Just like a properly installed transom or stringer when it's properly encapsulated in glass if this encapsulation is not penetrated by any outside source there's no way water can get to the wood core and cause rot. I truly believe we, as restorers, can sometimes, overthink and attempt to over-engineer things sometimes, due to worrying about the rot issue. Most of the rot issues were cause by poor craftsmanship or poor maintenance and upkeep. If we as owners take care of those two issues, ROT won't occur in most cases.

Well that takes care of this Old Dumb Okies Rant for this evening. Thanks for listenting!!!!

 

[Rick Stephens]

Thanks WOG. Appreciate your insight. Tomorrow I'll get to start glassing in some of this and sealing up the transom, Here's to some warmish weather for s few days.

 

[JASinIL2006]

Digital moisture meter showed up. I got the type with the sharp contacts sticking out that you stab the wood with. Definitely repeatable readings when moving back and forth.

The transom itself is all over the map.. Several year old stack of dry AC plywood in the shop is 8-10%. Several year old fir 2x4 from a stack of new wood in the shop, but now leaning against the porch where a little rain fell on it last week is in the 18-20% range. On the boat the wood around the bolt holes in the transom cutout area is 18-21%. The transom 8 inches up the starboard side is 31%. Lower down is mid teens to 25%. The transom up high is 8-10%. Highest I saw in transom was mid 30's. I expected bottom inch or so to be really high, but it wasn't as high (mid 20's) as the 30-35 up about 8 inches and off to the starboard side of the cutout by 8 or 10 inches.

Those readings seem pretty high... I thought anything above the mid teens was considered too wet to be finished. Readings in the 20s and 30s seem quite high.

 

[Watermann]

I used SS lags on my motor mounts with a heaping helping of 5200 to seal the holes.