MEP-803A - Rain proof hood

[mesias]

Hey guys,

I wanted to share a hood I had built for this unit and hear your feedback. The intent is to protect the unit mostly from heavy rain which is common in Fla. Most of the sound insulating foam lost the protecting coat and the rain would keep it endlessly wet. The hot air from rad is redirected to the back of the unit helped by an internal flap. The exhaust is also redirected to the side with some pipes. I tested the setup at full load (85%) for 45 minutes and no overheating issues. Below you can see a pic of the hood and HERE is a video of the test.

 

[Ray70]

Nice looking hood setup. Couple questions, have you since changed the exhaust pipe config? The video looks like you are susceptible to water getting in the pipe ( no flapper or 90* bend etc. )
Only other question is me wondering if the smoke shown in the video cleared up throughout your load test? Looks like some carbon burning off in the video, most of which should clear out after a good load test.

 

[mesias]

I have the pipe capped with a silicone cap/plug... I'm planning on installing a rain cap but it's difficult to find one in this size. Something like this should work fine, right?



About the smoke... I'm glad you mention it. This is not the first load test I run on this unit. The smoke never cleared out completely. In my ignorance I thought this was normal under load. I also noticed this last time around that it consumed a lot more fuel than before. This 45 min test moved the needle 1/8 down. Should the unit produce no visible smoke at all under load? I still can see some oily residue in one of the exhaust ports, could it be that the wet stacking was not cleared completely?

Thank you very much for your time.

 

[Zed254]

Rain caps are at Tractor Supply. Measure OD of your stack and visit store. I forget what size mine is......

 

[Ray70]

Usually once you get them cleared out you should have virtually no visible smoke until pretty close to or sometimes even above 100%.
You will vary slightly from 1 machine to the next, but in general you should get pretty close to 100% load with not much smoke. If you see smoke coming on way too early you either still have carbon buildup or 1 of the metering pumps may be adjusted incorrectly.
The best way to identify a mis-adjusted pump is to use an IR thermometer to compare EGT between cylinders or best way is to remove the exhaust manifold and you will see the offending cylinder right away. Although removing the manifold at this point may be a bit of work in your instance.

 

[nextalcupfan]

I looked at the video, It's a bit hard to tell but the smoke looks black.
Since you said 1 cylinder has some tar coming out of it my guess is either 1 injection pump is not metering properly or an injector isn't firing right.

 

[Coug]

Looks okay to me.
Coming from the RV and home standby world, there is enough air moving past the fan and out of the unit that you probably could have had the exhaust dump straight into the warm airflow out of the hood without any issues, thus removing the need to keep a flapper on the exhaust at all (except of course to keep out critters)

 

[nextalcupfan]

Looks okay to me.
Coming from the RV and home standby world, there is enough air moving past the fan and out of the unit that you probably could have had the exhaust dump straight into the warm airflow out of the hood without any issues, thus removing the need to keep a flapper on the exhaust at all (except of course to keep out critters)

If I remember right another person on here made a hood for his 803a, he said if you pipe the exhaust into it unless you insulate the hood it will reverberate and actually make the unit louder.

 

[Coug]

If I remember right another person on here made a hood for his 803a, he said if you pipe the exhaust into it unless you insulate the hood it will reverberate and actually make the unit louder.

That depends entirely on the design of the hood. If designed right there shouldn't be an issue, but often times that involves a lot of trial and error. Typically the gens I work with don't use a single point exhaust but use a long tube with lots of 1/8" or so holes in them for the length of it to disperse the exhaust and noise over a larger area.

 

[mesias]

Usually once you get them cleared out you should have virtually no visible smoke until pretty close to or sometimes even above 100%.

You will vary slightly from 1 machine to the next, but in general you should get pretty close to 100% load with not much smoke. If you see smoke coming on way too early you either still have carbon buildup or 1 of the metering pumps may be adjusted incorrectly.

The best way to identify a mis-adjusted pump is to use an IR thermometer to compare EGT between cylinders or best way is to remove the exhaust manifold and you will see the offending cylinder right away. Although removing the manifold at this point may be a bit of work in your instance.

I don't mind removing the hood and the cover, I just used a few bolts to keep it in place. I checked the temperature between cylinders on the outside of the exhaust ports and they are not the same, they are close but not in the same range. On top of it, the reading changes by moving the IR dot by just a 16th of an inch. What would be the most accurate way of checking this? What should I look for after removing the exhaust manifold?

I assume adjusting the IP would take rotating them to allow less or more fuel. If that's the case, clockwise increases the flow, right?

Looks okay to me.

Coming from the RV and home standby world, there is enough air moving past the fan and out of the unit that you probably could have had the exhaust dump straight into the warm airflow out of the hood without any issues, thus removing the need to keep a flapper on the exhaust at all (except of course to keep out critters)

The genset is in a very small space and I don't like the idea of sending all that exhaust directly against the floor. Eventually it could get sucked back into the intake.

 

[mesias]

I'll create a separate thread to discuss the smoke and keep this for the hood. Please reply about the smoke on THIS thread.

 

[ECS]

Hey guys,

I wanted to share a hood I had built for this unit and hear your feedback. The intent is to protect the unit mostly from heavy rain which is common in Fla. Most of the sound insulating foam lost the protecting coat and the rain would keep it endlessly wet. The hot air from rad is redirected to the back of the unit helped by an internal flap. The exhaust is also redirected to the side with some pipes. I tested the setup at full load (85%) for 45 minutes and no overheating issues. Below you can see a pic of the hood and HERE is a video of the test.

View attachment 809867

What tank is that? Looks like a perfect match.

 

[mesias]

I had it built for the MEP-803, HERE is the post with more details.

 

[csheath]

In their former life I doubt if they ever saw any shelter.

Mine sits under a shed. That said I would have wanted the electrical end covered if I chose one end over the other.

How many amps are you pulling in your load test? I don't think you can depend on the load meter. You can make any of them smoke some if you put enough load on it.

 

[mesias]

The load bank max pull is approximately 46A per leg at 240v, which is about 11KW.

I got he rain cap...