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-   -   Westerbeke 12d diesel mounted on lag bolted wood blocks (https://www.cruisersforum.com/forums/f54/westerbeke-12d-diesel-mounted-on-lag-bolted-wood-blocks-232584.html)

skkeith 08-04-2020 16:49

Westerbeke 12d diesel mounted on lag bolted wood blocks
 
3 Attachment(s)
Look at this motor mount hack job. This is possibly not the worst of the hacks done to this motor by the previous owner.

Attachment 212321

I should have intervened sooner but alas this happened first:

Attachment 212322

This split coupler (bottom) sheered at the bolts. Ignore the vice grips around the prop shaft (top).

My plan of attack is to replace all 4 motor mounts with df2205-2 mounts, removing the wood of course, and have an extender for the front engine brackets made to center the mounts on the stringers. Strangely enough the rear mounts are centered already...

I am replacing that custom fabricated split coupler with a solid coupler adding a rigid spacer where a drive saver would go to compensate for the size difference.

I have never aligned an engine before, and would really like any advice on how the heck I'll ever get this thing straight again...

What should I do about the attachment of the mounts to the stringers? Currently it is lag bolted, and this engine is not much more than 200 lbs, so should I just fill, drill and put new lag bolts in or do something else more secure? The integrity of the stringers appears good. The lag bolts were hard to get out and nothing is soft. Wood (stringer core) does not appear wet.

Attachment 212330



Thanks folks.

Lepke 08-04-2020 19:24

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
To align loosen the bolts on the coupling behind the transmission. Use a feeler gauge to check the difference in the COUPLING gap from side to side, top to bottom. Move the front of the engine away from the tightest gap. If the gap is tight on the top and open on the bottom, move the front of the engine down. Keep moving and measuring until the gap is within .002-.004" all the way around. I usually align within .002". More than .004" and you could have damage to the stern bearing and rear transmission bearing.

skkeith 09-04-2020 08:19

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
good, understood, but how do I place the new motor mounts? I am removing these 2x4 blocks (pic 1) and lengthening the motor bracket attached to the arm so the new mount will center on the stringer, but where do I drill the holes, should I put it all together without bolts and move the engine into position or what..................


and as an aside, since I sheared the coupler I assume because the blocks are cracked, "how do I know if my transmission is damaged." It appeared OK fwd/rev no abnormal noise, could not load it obviously...

DougR 09-04-2020 09:05

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
My suggestion would be NOT to extend the engine brackets to reach the center of the stringer, but to fabricate a pair of sturdy steel or aluminum brackets which you thru bolt to the stringer which then align with the existing engine brackets.

The reason for this is that when the engine is sitting on the flex mount stud, the force is pushing up on the engine bracket and levering the bracket against the bolts which hold the bracket to the block. If you extend the length of the engine bracket arm you effectively increase the leverage against the bracket attachment bolts and thus against the cast iron block. The bolts and the block may or may not be designed to handle this extra force.

I have seen engine support brackets pull out of blocks, along with a chunk of cast iron as big as your hand when the leverage was increased too much, both from extending the bracket length and also from jumping high performance boats off of big waves.

Far better to fabricate a bracket and bolt it to the stringer.......

skkeith 09-04-2020 09:30

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Thanks DougR, trying to picture your design. You are suggesting an upside down L thru bolted (w/ compression tube) thru the stringer, or should I put a C beam over the stringer and weld on (bolt on) the L to that?

stormalong 09-04-2020 10:17

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
First picture is weird. Third picture looks like the engine has completely broken loose. Is that right?

I would replace that hodgepodge mount with a piece of steel angle iron sistered (along side) and through bolted to the stringer. Build up the height with hardwood and through bolt the engine mount to the angle iron. For a two hundred pound engine that should do it.

One piece of advice I got from my engine supplier when I replaced my engine was that the engine bracket should be positioned low on the engine mount stud to minimize movement and stress. Use spacers under the engine mount to get that position low. I used aluminum plate but did not need the height that you do.

Why so much oil under the engine? Is there a leak?

skkeith 09-04-2020 11:41

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
the black under the engine is just the color of the epoxy under the paint. It is dirty and wet but not oily. The original A4 leaked oil probably but not this one.

In the 3rd picture it is hanging from a come along with the wood removed.

Why use a shim to get height if I can just mount the steel L beam 2" higher?

Also compression tubes through the stringer yes or no?

Also 2 3/8" bolts sufficient for thru stringer attachment?

And what about positioning the engine, I am currently thinking to block it up move it close then drill the holes..... but I don't know what I am doing.....

DougR 09-04-2020 13:39

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Quote:

Originally Posted by skkeith (Post 3112664)
Thanks DougR, trying to picture your design. You are suggesting an upside down L thru bolted (w/ compression tube) thru the stringer, or should I put a C beam over the stringer and weld on (bolt on) the L to that?

You could do it either way. Normally it is not considered “good practice” to do an L bracket cantilevered out to support the engine, as it can result in vibration. But in this case we aren’t working with an engine which weighs 2500 lbs, so I wouldn’t be concerned with it. What I would do, however, is to weld a triangular gusset between the horizontal and vertical portions of the bracket just to stiffen things up a bit.

I think qty. 2 of 1/2” holes per bracket thru the stringer should be enough.....no compression tube, as that might cause the loss of clamping pressure on the stringer.

One way to put all of this together is to carefully measure everything, drill all your holes and bolt it together and then align the engine as per Lepke’s description. Another way is to drill the 1/2” holes in the vertical portion of the L bracket and make slots for the flex mount bolts in the horizontal portion. With the engine hanging on your come along, loosely assemble the flex mount stud into the engine bracket, about 1/2 the way up, loosely bolt the L bracket to the flex mounts and softly clamp the vertical side of the bracket to the stringer. Then move things around until the prop shaft flange and the gearbox coupling flange are fairly well aligned and then drill the holes in the stringer. Then clamp the brackets to the stringer and you are 3/4 of the way finished. Finish up the final alignment as already described...

skkeith 09-04-2020 14:19

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Thanks DougR! How about some consultation on the coupler. After consulting with the local specialist he wanted me to replace the split coupler with a fixed coupler for strength. I bought a replacement fixed coupler and was having a 2" shaft extender disk fabricated (between transmission and coupler), but if I am moving the engine anyway might I not just move the engine back 2" and not add new parts?

Bill Seal 09-04-2020 14:41

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
If extending the mounts might put too much strain on their fastenings, and placing an offset load on those tall stringers could break them, how about a nice strong steel saddle from stringer to stringer, with pads for the motor mounts?

And an R&D flex coupling to take the stress off the shaft coupling.

SVTatia 09-04-2020 14:55

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Quote:

Originally Posted by skkeith (Post 3112289)
...

My plan of attack is to replace all 4 motor mounts with df2205-2 mounts, removing the wood of course, and have an extender for the front engine brackets made to center the mounts on the stringers. Strangely enough the rear mounts are centered already...

About these mounts, have you done any research? I am not criticizing your decision, but I have read (including MaineSails article below) that not every engine can accept any mount. But I am not sure how to check if the mounts are up to spec or of quality. All of this of course is to avoid the excessive Westy prices.

https://pbase.com/mainecruising/motor_mounts

DougR 09-04-2020 20:05

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Quote:

Originally Posted by skkeith (Post 3112897)
Thanks DougR! How about some consultation on the coupler. After consulting with the local specialist he wanted me to replace the split coupler with a fixed coupler for strength. I bought a replacement fixed coupler and was having a 2" shaft extender disk fabricated (between transmission and coupler), but if I am moving the engine anyway might I not just move the engine back 2" and not add new parts?

A good quality clamp coupling will work fine, as will a solid coupler.... If you go with a solid coupling it needs to be a proper tight fit on the shaft, and also needs to be faced perpendicular to the shaft centerline after installation on the shaft.

The shaft needs to be positioned so that there is approx. one shaft diameter “overhang” distance between the aft face of the cutless bearing and the front of the prop hub. This position can be maintained with a couple of hose clamps. Normally the engine is then moved aft until the propshaft flange and the gear box flange meet, and that’s the location for the engine. In your case, of course, the engine needs to become lower as it moves aft, as it’s moving down the angle of the prop shaft. If the two flanges can come together without the engine/ transmission interfering with anything then there shouldn’t be a problem with moving the engine aft. You need to maintain about an inch minimum clearance between the oil pan and gearbox and the hull. Also you might find it necessary to trim the stringer height a bit where the rear mounts sit.

stormalong 09-04-2020 21:26

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Quote:

Originally Posted by skkeith (Post 3112783)
the black under the engine is just the color of the epoxy under the paint. It is dirty and wet but not oily. The original A4 leaked oil probably but not this one.

In the 3rd picture it is hanging from a come along with the wood removed.

Why use a shim to get height if I can just mount the steel L beam 2" higher?

Also compression tubes through the stringer yes or no?

Also 2 3/8" bolts sufficient for thru stringer attachment?

And what about positioning the engine, I am currently thinking to block it up move it close then drill the holes..... but I don't know what I am doing.....

Offsetting the angle iron higher depends on the size of the angle iron. I would want at least two thirds of the surface against the stringer. Keep in mind that the strength of the mount is in the surface area of the mating surfaces. The bolts are there to keep those surfaces tight against each other not to directly carry the load. 3/8 inch bolts should be plenty strong but the quantity should be determined by the length of the angle iron. If you are using one long angle iron for two engine mounts I would go with four bolts. If your stringers are solid hardwood you do not want compression tubes. You want the bolts properly torqued to set up enough tension to hold the bracket tight to the stringer, that is also why I suggest more bolts. Compression tubes would interfere with that tension. Use a torque table for the size and grade of bolt you use. Use thick washers under the bolt head or nut where it is against the wood - again because the goal is for a tight bolt. Use proper lock washers too.

If your kluge wood brackets were in the proper place for the engine position I would start by putting that back together temporarily for a baseline measurement. If your replacement engine mounts are a different height then you can adjust from there. Most engine mounts have elongated slots, one in each direction so they can be moved for alignment. If you are dealing with only a 200 LB engine just set it down on your angle iron brackets, do a rough alignment and mark were to bolt the engine mounts. you have a lot of flexibility to move the mounts within those elongated slots. A two hundred pound engine is very easy to move accurately with simple levers such as crowbars and two by fours. When I installed my 600 lb engine it was easy to move with levers - only 150 lbs on each mount. It is deciding which way to move them that requires thought.

Reading about your shaft coupler, have you considered using a flexible coupler? If you want to space it out two extra inches that may be a good way to do it.

skkeith 09-04-2020 21:51

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
The facing process is news to me DougR. I am trying to do this in the water. A split coupling will make this not necessary? Can you recommend a supplier for a quality clamp coupling, the solid coupling is 50MC004075 Solid Buck Algonquin Marine Motor Coupling.

skipperpete 10-04-2020 04:20

Re: Westerbeke 12d diesel mounted on lag bolted wood blocks
 
Quote:

Originally Posted by stormalong (Post 3112727)
First picture is weird. Third picture looks like the engine has completely broken loose. Is that right?

I would replace that hodgepodge mount with a piece of steel angle iron sistered (along side) and through bolted to the stringer. Build up the height with hardwood and through bolt the engine mount to the angle iron. For a two hundred pound engine that should do it.

One piece of advice I got from my engine supplier when I replaced my engine was that the engine bracket should be positioned low on the engine mount stud to minimize movement and stress. Use spacers under the engine mount to get that position low. I used aluminum plate but did not need the height that you do.

Why so much oil under the engine? Is there a leak?



Totally agree stormalong. It looks like the engine bracket in the first pic has snapped off near the end and a temporary fix is the bolted block to support the now un attached mount and bracket end. Seems like the snapped coupling bolts might only be a symptom.


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