Engine Insulation Charring

[gottogetfishing]

We are the proud new owners of a 2012 R-27 and have some charring on the insulation. what do you recommend to help stop this and prevent it from happening again.
It looks to me like the thinner insulation was installed in the wrong place, is this the way it comes from the factory or was it patched by the last owner?
The engine is coming up on 1000 hours so there is a good amount of travel done but I feel it still should not look like this.
Thanks
John

 

[baz]

If that charring, as you've described it, is sitting above the turbo heat shield it's IMO understandable as that heat shield will get very hot when engine running at high RPM.

The hole in the installation might be of concern.

Some sooting on the insulation (much like you see on the air filter fins) is to be expected as, let's face it, the engine is a diesel and sooting can occur.

You might also check the V-berth's aft bulkheads on port and starboard sides to see if there's any trace of sooting streaks on the fur. I had this issue on my previous R-25 (Classic) with a 4BY2-150 diesel engine after having run the engine for around 100 hrs.

 

[knotflying]

I fabricated a thin piece of aluminum, about 8" X 8" and screwed it in at that identical spot. I screwed it down tight enough to squeeze the insulation down a bit and to clear the turbo a bit. So far so good. I am going to the boat and will take pictures. Crew Dog did the same to his boat and I actually used his as an example.

 

[baz]

I also note that one of the beauty plate bolts is missing in the photo you posted. I would obtain a replacement bolt and secure that plate as a loose beauty plate can develop a nasty and very annoying rattle at certain RPM. In fact, check all the beauty plate bolts for being securely tightened down to avoid RPM developed harmonic-rattles.

 

[Crewdog]

Here's the thread and pics from original post:

http://www.tugnuts.com/viewtopic.php?f=24&t=8042

 

[baz]

The heat shield acts as a block to radiant heat from the turbo fan casing. Without this shield in place the radiant heat can be imposed on the hatch cover and do damage to it, such as melting and warping. The extra insulation material on the shields underside helps to reduce the surface temperature of the shield to presumably acceptable levels for avoiding heating the hatch cover area that people have shown to be charred. The Yanmar advice about replacing the heat shield is there presumably as they predict the heat shield and it underside insulation's performance becomes compromised after 250 engine hrs. IMO, people should take note of the Yanmar advice.

The turbo casing can get very very hot and I've mentioned elsewhere, this casing can in fact glow red when engine run at high RPM for extended periods or even for short periods.

The engine compartment requires cool air flow flow to not be constricted. This cool air is drawn from the side lockers and the hull vents nearby. The air from the side lockers enters the engine compartment through gaps at top of the locker's inside walls adjacent to the engine compartment. Thus, it's important not to place gear (especial soft gear) in these side lockers that can impede or block these air slots. If these air slots are blocked to any degree diesel sooting inside the engine compartment can occur and be carried/sucked down along gaps into cabin areas, and as far down to the V-berth area. This aspect is obviously undesirable.

 

[knotflying]

 

[Dale777]

gottogetfishing,

On my previous 2012 R27 with Yanmar engine, I had the same type of charring on the insulation above the turbocharger. My solution was to install a high temp heat shield on the underside of the engine hatch, the same as scross did. See this link for the material I used:

https://shop.advanceautoparts.com/p/des ... 16120025-P

The specs are: Aluminized surface reflects up to 2000°F radiant /1200°F direct /continuous heat

I used the heat screen to cover a much larger area than was charred, then taped it with aluminum tape all around the edges.

 

[gottogetfishing]

Thanks so much everyone for your excellent ideas. I'm going to weigh the advise and work on this. Thanks again!