Floor problem - Any idea?

Here's the situation. I'm in the process of replacing my floor in my Marine Trader. The parquet is in bad shape and the plywood underneath is soft in some places.

When I bought the boat, the PO had modified the trap above the engine (Flord Lehman 120) because the trap was resting on the expansion tank (picture 1). I figured it was because the floor was sagging a bit so I went and got some jackposts and raised the beams underneath until they were straight again.

But even now that the beams are straight the trap is sill resting on the expansion tank. The trap is still about 1 1/4 inch too high. I'm going to put a 3/4 plywood before laying the new floor but there is no way I can compensate that much. Any idea?

Fotoman wrote:
Here's the situation. I'm in the process of replacing my floor in my Marine Trader. The parquet is in bad shape and the plywood underneath is soft in some places.

When I bought the boat, the PO had modified the trap above the engine (Flord Lehman 120) because the trap was resting on the expansion tank (picture 1). I figured it was because the floor was sagging a bit so I went and got some jackposts and raised the beams underneath until they were straight again.

But even now that the beams are straight the trap is sill resting on the expansion tank. The trap is still about 1 1/4 inch too high. I'm going to put a 3/4 plywood before laying the new floor but there is no way I can compensate that much. Any idea?

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Original engine??* Motor mounts??*


-- Edited by JD on Monday 13th of February 2012 01:14:09 PM

From the pic it doesn't look like any of that is new.

Perhaps you could router out the space for the expansion tank.

make the sole Thinner over the tank.

Or cut a hole and cover it with carpet. Short of lowering the engine or raising the entire sole.

That is a tough one.

I kind of fall back to JD question.

Re fit's can require extensive modifications

SD*

Original engine, yes. I want to avois having a raised section above the expansion tank. Looks so bad. Maybe I'll have a look at the engine mounts.

Not a bad idea skiperdude but I already made it thinner above the tank. Can't make it much thinner without compromising the entire panel.

-- Edited by Fotoman on Friday 10th of February 2012 04:09:24 PM

I can't imagine that it left the factory that way. So with that said, here is what I found when I removed the fuel tanks for replacement, the ends of the floor beams were rotten and the whole house had settled but not to the point that it appears yours has. See if you can look over the top of your fuel tank and look at the point where the beams rest on the ledger to determine if they are still in good shape. Harbor Freight sells an inexspenive bore scope that will reach in about 3 feet.

*

The floor did not settle because you can see by the cabinet door clearance, so it appears the engine height for some reason was raised?* The easiest would to increase the height/level of the floor to match the hatch height since you are replacing the floor anyway.


-- Edited by Phil Fill on Friday 10th of February 2012 04:45:18 PM

Is there any way to relocate the expansion tank?

Phil Fill wrote:
*

The floor did not settle because you can see by the cabinet door clearance, so it appears the engine height for some reason was raised?* The easiest would to increase the height/level of the floor to match the hatch height since you are replacing the floor anyway.



-- Edited by Phil Fill on Friday 10th of February 2012 04:45:18 PM

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*Are you sure the cabinets did not settle with the floor?* See the post above about beam ends on the ledger.

It appears to me that the besto solution is to move the expansion tank to somewhere that you could access it by removing an access plate rather than the entire hatch?

I will check about the beam ledgers for sure. That's what makes the most sense. Should be pretty easy since I removed the old fuel tanks last year so access is pretty easy.

Does anyone know if it's possible to relocate the expansion tank on a FL 120?

Willy wrote:
I think Marin used undersized mounts for this reason. GB 36 did not have the room for the correct size and they built designed the boat around the undersized motor mounts? So he stayed with the original system.

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*Correct.* But only in the GB36 twin.* The single has plenty of room above the expansion tank.* However I don't know if the factory used the next size up mounts on their single GB36s or not.

The only solution I see from your photos is what others have already mentioned--- some sort of routed out recess on the underside of your engine hatch to accomodate the expansion tank.*

Even if you wanted to go to the expense and hassle of changing the engine mounts, the next size down from the "correct" mounts is not that much shorter.* And then you get to play with the issue of realigning the engine and shaft.

I assume your installation is a factory installation.* If so, how did Marine Trader deal with it originally?** Is there an MT owners forum you can ask*or other identical boats in your area that you can compare to?

Fotoman wrote:
Does anyone know if it's possible to relocate the expansion tank on a FL 120?

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*The person who can answer that is Bob Smith at American Diesel.* He did much of the orgiginal marinization work for Lehman way back when and he and his son Brian probably know more about the Lehman than any other folks around.

However, while anything is possible if you throw enough money at it, the expansion tank in its current position would be a challenge to move.* It is bolted to the thermostat housing underneath it, so moving the tank would require fabricating some sort of connection to the now-exposed and open thermostat housing.* I suspect making some sort of accomodation in the hatch for the tank would prove to be a far, far more practical solution than moving the tank.

But talk to the Smiths at American Diesel.* They can tell you exactly what's possible and what isn't on that engine.

Unless it is "hard plumbed" there should be no reason not to. the expansion tank on your vehicle is remotely mounted. Just needs to be the highest point in the system.

oops typing while others with more knowledge were also . . . .

Marin is right. Bob Smith is an encyclopedia of information on those installations. No doubt, he knows of a part # to use for remote mounting of the tank. He was bound to have installed that engine in something that had that clearance problem. Don't be surprised if he remembers the boat, the engine, and even the part number.

It seems to me the expansion tank and heat exchanger take the place of a radiator. It is mounted where the thermostat and upper radiator hose would have been- were it a tractor application. So if you were to locate/ purchase the original thermostat housing and mount it where the original was, purchase a second one to bolt to the bottom of the expansion tank (the bolt pattern would match) and then relocate the tank to the side, keeping it as the highest point of the cooling system (as was mentioned) , you would have the cure. You would run a coolant hose from the new "thermostat housing" to the bottom of the E tank, and the remaining E tank hoses would be replaced with longer ones that connected in the same place as the original ones. Am I missing anything here?

You could cut the tank in "half" making it shorter, then remove the sides of the upper part, then weld that top back on. That would give you a smaller but shorter tank with out spending very much. That is just a welding job.

*

Then you would need a coolant overflow/recovery tank. You might already have one as that is one of the Bob Smith "upgrades". Most of the trawlers I have seen with Lehman 120s have added the recovery tank.

OR you could remove the tank, cut off the connecting piece that bolts to the engine, and have a new shorter but wider tank made to keep the same volume. This would not be very expensive either.

There's two possible solutions.


-- Edited by jleonard on Saturday 11th of February 2012 09:39:05 AM

Well this morning the dog got me up at 4:30 to go outside and pee*and when I got back*into bed the only thing I could think about was your problem.* Don't know why.

Like a lot of times it seems to me that*folks*jump to conclusions and fixes that may in fact work but do not address the real problem.* Happens all of the time when someone has an engine problem.

First off the boat did not leave the factory with that engine sticking through the floor hatch like that.* Everyone agrees?* So the answer to the problem is how did it get that way.* If we think about it, as I did for a couple of hours this morning, there are a couple of things that can be checked fairly easily.* For starters either the floor is falling through the engine compartment or the hull is coming up to meet the floor both of*which I guess*are possible but highly un likely because from the pictures*something has*moved 2"s or so.* But this can be verified I would think.* Just measure the number of inches from under the floor to the hull at several points.* I would start at the front of the engine*with either side of the tank in question down to the bilge bottom.* Then half way back on either side and then again matching the front measurements on the aft edge.* Now get someone with a Marine Trader like yours to do the same thing and then compare the measurements.* My guess is that the floor isn't falling into the bilge, because if it was there would be other problems like doors won't open or close, especially if it fell 2"'s.

Now go into the bilge and get a measurement on the engine from the top of the tank to the bottom of the oil pan.*It would be interesting to know how much room there is between the oil pan and the hull. *My guess is that that engine is setting four or five inches off of the hull when it probably should be maybe an inch or so off of the hull.*
So let us say for argument sake*that the distance between the bottom of the floor and the bilge bottom is 42"s.* And the total height of the engine at the highest point is 36"s.*That is a 6" difference* so if you lower the engine to with in 2" off the bilge that will give you near 4" up top.* My guess is that*some one has changed the mounts or the support brackets for the mounts with out regard to how the hatch fits.* Why?* Who knows, either that is what was available or they wanted to be able to drain the oil out of the engine by way of a plug on the bottom or some other strange reason.* The engine needs at least* 2"clearance*between the radiator cap*on the tank and the bottom of the closed hatch*at the top so that it has room for movement as it is put under torque.
Moving the engine is easier than reflooring the whole salon.* Besides if*the engine*is up to high that affects the*alignment with the stuffing box and that*can't be correct.
The question that comes to mind is how the hell did this get past the survey?**None the less*no matter what the problem is I would fix it correctly because anything else you do may not get past the next buyer or survey.
Good luck and let us know what you find out.


*


*


-- Edited by JD on Monday 13th of February 2012 01:14:58 PM

Agree with JD's sleepless thoughts...

Been rebuilding boats recreationally for*45 years and professionally for 12.* Can't believe how many "non-fixes" I've had to redo.* Not that all of mine are perfect...but most can be lived with.* The pic of that floor has me completely clueless as to why it was done and how it stayed that way.

I'd have to see the boat...everything I can think of...as many others have stated are not*fixes , they are patches....I'd have to see a lot more before I would even recommend something because anything else so far is just a guess.


-- Edited by psneeld on Saturday 11th of February 2012 10:45:07 AM

jleonard wrote:
You could cut the tank in "half" making it shorter, then remove the sides of the upper part, then weld that top back on. That would give you a smaller but shorter tank with out spending very much. That is just a welding job.

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*Not a good idea at all.* The tank's height and the coolant level in it is critical to maintaining the correct level of coolant in the Lehman cooled exaust manifold.* Any expansion tank, remote or otherwise, needs to maintain this height relationship between the coolant level in the tank and the position of the exhaust manifold.* If the tank is too low, or if the level of coolant in the tank is too low, an air pocket will form in the cooling passsages at the front of the exhaust manifold.* This part of the manifold will then get extremely hot and severe internal damage will occur..* As these Lehman manifolds have become almost impossible to get anymore, ruining one could conceivably mean a re-power would be necessary.

This is a case where any suggestions from an internet forum should be ignored and the owner should go directly to the Smiths at American Diesel.* The surest way to kill a Lehman 120 is to ovreheat it, even a bit, and the potential for screwing up the cooling system by shade-tree solutions to the cooling system is too great in my mind to warrant home made remedies, however logical they may seem.* Call the Smiths. 804-435-3107.

PS--- I should have said "any suggestions from an internet forum regarding modification of the cooling system."* The ideas from JD and Scott regarding the engine's physical installation are worth heeding in my opinion.


-- Edited by Marin on Saturday 11th of February 2012 10:50:03 AM

Old Stone wrote:
Run a string one side of the ledgers to the other as suggested. Definately not a factory install, but if you were to mess with the the engine mounts, you may have some alignment problems with the shaft. How about an inspection plate right above the cap? Very thin and strong. Maybe 6" diameter. Any flex in the floors now?

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Carl,

An inspection plate is just another patch and is not fixing the real problem.*

I agree that the alignment is important but the tail shaft might not be at the wrong height.* Maybe just the front of the engine is jacked up. We will not know until he does some measuring.

I have seen a different style expansion tank that was mounted along the of the engine with a pipe coming out of the end and going to the point where your tank is mounted. It was a
ford engine but I believe it was a Sabre conversion. What is of most importance is why is it like that and how do you fix the root cause, not how to work around it.

I am not saying this is likely but, is it possible that the engine was moved forward from its original position?* If so, it would have to move up if shaft alignment were held.

I am a glutton for carpentry projects and I think I would somehow move the face of the cabinet aft to include the expansion tank in the lower part of the cabinet.

Make the hatch shorter to compensate and put a false floor in the cabinet that could be lifted out to access the expension tank cap.

It is a lot of work but everything could be nice and level.

*

Of course if it is possible to move the engine aft and lower that works too, but that is a lot of work also.

Do you* like woodwork or engine work? Take your pick.

JohnP

Fotoman wrote:
I will check about the beam ledgers for sure. That's what makes the most sense. Should be pretty easy since I removed the old fuel tanks last year so access is pretty easy.

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**********Were the fuel tanks held in place by heavy wooden upright supports?* If these were removed and not replaced the floor beams could be now sagging.

**********Just a thought** JohnP


-- Edited by JohnP on Sunday 12th of February 2012 06:57:50 AM

Fotoman, my boat is basically the same as yours, only older, and without the hardtop flybridge extensions.* I have the same engine, and, as you can see from my pic, taken from virtually the same place and angle as yours, there is room for the expansion tank without dodgy excavation of the floor hatch.* In fact there is a couple of inches or more clearance.* Like others have said, I doubt the floor has shifted that much or everything would be visually out of line.* Therefore your engine must have been raised at some point.* I suspect someone just installed oversized engine mounts, as it is hard to imagine any other intervention requiring the engine to be moved forwards, however, if oversize mounts were installed, the front would have had to be raised to re-align the shaft, and that could well account for what has happened.* Taking out a section of the floor was a bit of a "Heath Robinson" way of fixing it, but if that is what has happened, and the engine and shaft are in alignment, then all is in working order, and you might be best to leave it that way.* If you are replacing the floor, then some creative carpentry to accommodate the raised tank might be in order, as I agree with Marin and others who have counselled against moving or altering the tank, and my inclination would be a local fix, rather than raising the whole floor - a major issue, which would affect all the cabinetry and headroom as well.

Amazin'. I never cease to wonder how and why stuff like this seem to occur on our boats. I've had my old trawler about 6 years now, and continue to uncover "Why the #@$% did somebody do that?" situations.

*

I guess it's all p[art of the fun and romance of collecting these antiques.

A lot of comments/suggestions. I will spend some time this week to investigate more in light of what some of you have said. Maybe the engine was moved forward (therefore raised to keep the alignement) to accomodate a new transmission at some point? This would be the most logical explanation for the engine to be that high. Anyway, I will post my progress. Thanks for your help.

JohnP wrote:Of course if it is possible to move the engine aft and lower that works too, but that is a lot of work also.
Do you* like woodwork or engine work? Take your pick.

JohnP

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*Lowering the engine to it's correct height will fix the problem and that can be done in one day unless someone has done something really dumb and that could be the case.* If lowered as was the original design then there is no need to move it back.

None of the woodworking projects are one day jobs and any one of them will could effect the next survey to sell the boat.

I'm a little disappointed that we haven't heard back from the owner as to what the measurements are under the engine and what was put under it to merit this height change.

Fotoman wrote:A lot of comments/suggestions. I will spend some time this week to investigate more in light of what some of you have said. Maybe the engine was moved forward (therefore raised to keep the alignement) to accomodate a new transmission at some point? This would be the most logical explanation for the engine to be that high. Anyway, I will post my progress. Thanks for your help.

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Sorry Eric I was posting at the same time you were.* I don't think a transmission change would be the cause of the height difference.* It could have been moved forward with out changing the height.*Besides it doesn't look like it has been moved forward but just up.*Also most of the time if the transmission has a longer tail shaft than the one that comes out the correct repair is to just shorten the prop shaft.* Well that is not 100% correct either, the correct repair is to fix the one that came out or replace it with one that fits.

Take some pictures when you get in there and let us know what you find.

You may be able to lower the engine using a flexable shaft coupling. I do not know how much miss alignment the flexable coupling can accomadate. Try and determine if the engine was moved forward, perhaps because a longer shaft was installed or to get a new purchase on the stringers due to failed mounting points or to install a generator behind the engine. My MT suffered from rot in the stringers, there isn't that much wood in there as mine had 3 inches of mahogany on top flanked by plywood on each side with 2 inches of mahogany on the bottom. If the engine was moved forward it would have been raised to maintain alignment with the shaft. With that said, can you move the engine to the rear, which will lower it. Imagine a line running through the center of the crankshaft, transmission and inline with the shaft. It will be approximately paralell to the exhaust manifold, you can see how the engine moving along this line will be lowered when moved to the rear and raised when moved to the front.