A question about the crossbeam forward of the engine room below the floor

[Eddie Offermann]

I have a question that I'm hoping someone will be able to give me some information on.

Since the old MB180D engine that's been with this boat since she was brand new had not only become problematic in recent years but had become extremely difficult to get parts for, I bought a new engine. (Well, new to me!) This one adds about 10HP or so over the last one, and takes many parts in common with a myriad of other diesel engines. Problem is, as the mechanic got down to do the real work, he realized that this engine is a bit too large for the engine compartment.

We can take a few inches, maybe 4, off of the prop shaft, if absolutely necessary, and we can carve away at the supports for the old engine and make some adjustments topside for the filler for the cooling system. We need to extend several inches towards forward. There's space to do so, with the loss of a small amount of storage, some of which is difficult enough to make use of anyway.

We're curious about the crossbeam forward of the engine room. We're pretty certain it's structurally significant, and I assume it is primarily concerned with bearing beam-wise compression load but we're curious what its load requirements might be since we may end up carving into it. We have plans to sister it, but there are issues with that as well since our space to do this is fairly limited - so it's likely to be sistered with a piece of solid aluminum or steel.

Basically - any information that anyone can give us about this piece, what it is attached to on the sides, and what load it is intended to bear would be helpful.

I tried to take a picture of it but since the entire area down there was freshly cleaned and painted in grey bilge paint, it's hard to make out any meaningful details in a photograph.

Thanks for your help!

[bob mitchell]

by "crossbeam" do you mean the plywood bulkhead immediately in front of the engine beds? Make a quick and dirty top view diagram of the engine and the dimensions you are talking about if you feel like it, and maybe scan or photogragh and post  because I find this topic really interesting and worthwhile for future information.  There is a book titled "The Boat Owners Fitting Out Manual" by Jeff Toghill that has a whole chapter devoted to engine installation -BUT a most interesting idea he presents is that of making an ENGINE TEMPLATE out of plywood, which basically is three pieces of plywood, each a silhouette of the profile in one dimension, and then all fastened together. So now you have a really light weight three dimensional representation of your engine which allows you to really check out engine mount locations, bulkhead spacing, as well as rough in engine alignment.

[Eddie Offermann]

Well, there's the plywood bulkhead - but on my boat, along the top of the plywood bulkhead is a 1-1/2x6 (not a 2x6) that runs across the engineroom. There are tanks on either side of the engineroom, so I can't see where this beam runs to in order to determine how structurally significant it might be. The fact that it's a 1-1/2x6 (it's barely 1-1/4" thick) leads me to believe it might not be as significant as we'd initially suspected.

 

My mechanic is building an engine template so we know exactly how little carving away we can get by with. What we're most concerned with is how much we need to compensate for what we remove of this beam. It would be ideal if it turned out not to be structurally significant at all, but was just there to provide a top member to secure the plywood bulkhead to. We intend to notch out a portion of the bulkhead, which will probably include some or all of this cross member.

 

I've attached a photo of the area. Light's a little better this morning so the picture came out better than what I'd attempted to take last night.

[bob mitchell]

What a great looking engine compartment. My initial take, and I am in there on my boat as well, is that a lot of miscellaneous things are fastened to that wall, possible on the other side as well - but I don't think it is too structural. Aren't the steps on the other side?

      I will look some more, but my intial take, that you could check, is that there may be a seam in plywood pieces along that board. You know the cabin is built separate and then lowered onto the deck - see if that perspective helps any.

     But I tell you, I really want access to the front of my engine, so I am planning an oval cut out in the plywood bulk head that should not significantly weaken the boat - kind of like a lightening hole in a light weight beam - then I can get to the whole front of the engine for maintenance. (that will be behind the steps, which will be a little different, with room for two fuel filters, one for each tank, and a couple of pumps - sort of like a small utility "room".

[Eddie Offermann]

That's almost exactly what we're planning (except that I'm going to have some interesting diagonal stairs since I basically have to add about the width of the top stair to the engine room). But the long and short is, this will enable me to have an access panel to the front of the engine.

The steps are directly on the other side (that and the countertop where the sink is).

[bob mitchell]

right!!!   That spaced under the stairs can be utilized, for sure. You never said what kind of engine you got.

[Eddie Offermann]

Oh - it's a Waukesha 180DLC. Mostly used on tractors and gensets. I haven't been able to find a really good reference for the HP of it, but it's a bit more than the MB180D that was in here before, and compared to the Benz engine, seems much more accessible for parts since there are a number of parts that it shares interchangeably with a wide variety of other tractor engines.

[bob mitchell]

so what about the marinization? who did those parts? NOTHING LIKE A GOOD TRACTOR ENGINE!

[Eddie Offermann]

The engine came out of another boat, so I'm not sure who did the original marinization. It's freshwater cooled, with a heat exchanger. In looking up info about the engine, I've run across the occasional reference to it in another boat, so there may have been someone marinizing these commercially at some point.

[bob mitchell]

great - hey - pretty cool to talk - sent you a message with a link for a manual.

[Clyde A. Phillips]

I have emailed both Eddie, the original, and Bob, a copy, my reply to Eddie concerning this question.  Eddie's picture and Bob's remark about the possibility of the beam being a butt block joining the bottom and top pieces of that bulkhead makes me think Bob is on the mark.  The lower part of the bulkhead would be attached to the frame across the bottom and up the sides (probably on the forward side of the frame).  The upper parts (two of them) complete the bulkhead and are attached to the frame on the sides and the beam across the bottom.  These upper parts form the passage way to the main cabin.  The beam and plywood bulkhead does add strength and acts somewhat like what the Chesapeakers call a strongback, though they are not similar in construction.  But so far as the beam goes, I don't think it is all that important for the total strength of the boat.  Notch it out for the engine then sister it if you can.

Then since you will be moving into the step area with the engine you can redesign the steps so they can be removed when you need access to the front of the engine.   I see no problem with your plans for this engine installation.

[Dennis Gaffney]

Eddie,

I agree with Clyde. Having done post mortem on my Newporter and seeing it from the inside out, it looked to me as if the plywood bulkhead and crossbeam would help square the hull, but the exact placement was probably not vital to the structural integrity of the hull.

Dennis