Work Load Advise - Damper, Motor Mounts, Exhaust Elbow

[MikeHoncho]

With my new prop came more load on the engine which brought about a chatter. I believe it is a combination of aged motor mounts and a worn damper plate. The mounts are really collapsed in the rear and the vertical adjustments are maxed out. No question the mounts need replacing regardless of if they are culprits but I'm certain there is a alignment issue due to them. While doing this, I'm going to replace the exhaust manifold, coupler and riser.
I'm pondering the best way to get to the damper plate. Normally the easiest would be leaving the engine in place and do it from the back side but in the 78 30's there is a small access hatch on the port side and a fairly narrow access opening on the starboard that runs the length of the lazarrete. To do it from the rear I would need to remove the rear portion of the bulkhead on the port side, 8D Lifeline AGM that sits in front of the fuel tank, fuel tank for my Wallas stove and hot water heater from the lazzarete. No undoable but the hot water tank would be a pain.
I'm considering removing the whole engine and tranni as one and work on it on the sole. Any method would require D/C'ing the exhaust at some stage, prop shaft. I would defiantly go with removing the engine but the weight and how to get it out of the cabinet with such limited access to lifting it.

I'm interested in your point of view on my options.

 

[RoyS]

I have a similar boat. Have you considered removing the plywood enclosure surrounding your engine? On my 1980 H33 it is fairly easy to remove. That may give you enough access.

 

[Sailgunner]

I question why there is more load on the engine. Can you still reach your max RPMs? If not your prop is not correctly sized and you can damage your engine.

 

[MikeHoncho]

I have a similar boat. Have you considered removing the plywood enclosure surrounding your engine? On my 1980 H33 it is fairly easy to remove. That may give you enough access.

The countertop is Corian and I’d have to remove the whole thing, doable but a real pain. The port bulkhead that encloses the engine compartment from the quarter birth has all my electrical mounted on it (on the engine side) so that’s not coming out. I can though remove it from the access hatch back though.

 

[MikeHoncho]

I question why there is more load on the engine. Can you still reach your max RPMs? If not your prop is not correctly sized and you can damage your engine.

I installed a Autoprop that is self pitching that loads the engine more that the previous prop. I can reach max rpms.

 

[MikeHoncho]

Going off of my "while it's out" theme.......I'm considering lapping the drive cones on the transmission while I have it out. I do not know the hours on it as the vessel was repowered. No issues with slipping and shifts in and out fine.

 

[ggrizzard]

When I repowered, I removed the port side, quarter berth rear bulk head.
I think it was 4 screws. Then I removed the hinged, step platform above the ladder. It was three screws, I think. Then I removed the port side engine bulkhead.
That is the easiest way to get the engine out.

Because of the problems associated with the small opening in that 'wall',
I made up two pieces of veneered plywood to replace the single bulkhead.
The first covers the engine bay up to the cockpit fiberglass well. I permanently mounted this section to the forward frame at the pull out steps
and at the support beam.
The second piece begins at the fiberglass and continues aft to the rear bulkhead position. It is removable with three screws. The magic part of the scheme is that
Hunter made the portside, cockpit seat with a 'lip' on the inside at the top.
I slide the panel in at an angle, and move the top edge into the slot formed by
the 'lip'. Then I place a common length of angled aluminum rail abutting the bottom edge and put three screws into pre-drilled holes in the aluminum and the quarter berth platform.
Now I have the majority of the engine bay available for routine maintenance or major repairs.
If any of this sounds interesting, I can take pictures.

 

[ggrizzard]

FYI, I made several amendments to previous post.

 

[MikeHoncho]

I pretty much did the same thing previously but opposite. I made the bulkhead into two pieces and made the rear removable from the original access hatch back. The forward section isn’t going to be moving being all the electrical systems I installed on it.

Im thinking I’ll take it on from the rear sides and if I don’t have enough room then I’ll remove the fuel tank for more room. I installed the platform and fuel tank about 3 years ago when my original tank leaked and saturated the whole thing. The pictures are the “work in progress “ I still needed to i stall the SG2000 battery monitor shunt that went next to the regulator and under the battery switch.

 

[MikeHoncho]

A little follow-up. I decided to forgo the dapper plate. I removed the battery (8dAGM) from in front of the fuel tank and the exhaust riser. Replaced the motor mounts each side at a time with the engine propped up from the oil pan via woodblocks. It would have taken about 20 minutes with proper access. The time burn was aligning and finding a balance between obsessive-compulsive and logical. I got it to within .006 gap. That took the longest. I'm a little concerned with the laggs on the port side. They wouldn't crank down tight tight, just snug but that is how they were previously. The new mounts are about 3/16ths taller than the old ones and that is when they are not loaded. The engine doesn't shake the whole rig when idled down now. I actually can idle it down to the throttles lowest point. I hadn't done that since I owned the boat due to vibrations.
The old exhaust elbow is about 3/4 blocked from what I can see looking up into it from the discharge side. I'm going to try to cut it in half for a better look. Replaced a section of exhaust hose between the elbow and 90 degree turn to the muffler. It was bubbled up inside due to, what I believe, when the water feed elbow in the exhaust elbow clogged and didn't allow water into the exhaust for about 20 minutes.
Two days later and about 18hrs (a lot of water breaks and a couple runs to the store) it's all back together. Mounts were $700, exhaust hose and 4 marine clamps was $80, stainless exhaust manifold, coupler and elbow was $300. All and all I'm glad I didn't put it off given the condition of the exhaust elbow. The motor mounts were intact but worn badly.

 

[RoyS]

Regarding your lags: Sometimes you can drill a few inches deeper and use a longer lag. Sometimes you can use a thicker lag. Or, you can drill out to a larger dowel size and glue in a length of dowel, then drill again for your lag.

 

[MikeHoncho]

I've put about 10 hours on the new mounts, shaft alignment, exhaust and everything seems to be working as planned. The clanking heard previously is gone. I got a little worried when I first got it up to temp and cruise speed as I found the cabin with light smoke it in but it smelled like paint. Turned out to be the antiseize cooking off from the elbow thread coupler. All is good now and I barely have any water coming out of my stern "pee hole" that shows water going through the system which is indicative of increased flow through the elbow compared to before.